Material and manufacturing technology v

Dargusch 136 Compressive Properties of Solid and Porous Parts Made from High Strength Steel Alloys by Direct Metal Deposition Computational Analysis of Single and Multiple Impacts of Low

Tai ngay!!! Ban co the xoa dong chu nay!!!

Material and Manufacturing Technology V

Edited by Meixing Guo Syed Masood Ghenadii Korotcenkov

Asif Mahmood

Material and Manufacturing

Technology V

Selected, peer reviewed papers from the

5th International Conference on Material and Manufacturing Technology

(ICMMT 2014), May 8-9, 2014, Kuala Lumpur, Malaysia

Edited by

Meixing Guo, Syed Masood, Ghenadii Korotcenkov and Asif Mahmood

Copyright  2014 Trans Tech Publications Ltd, Switzerland

All rights reserved No part of the contents of this publication may be reproduced or transmitted in any form or by any means without the written permission of the

Full text available online at http://www.scientific.net

Preface

2014 5th International Conference on Material and Manufacturing Technology (ICMMT 2014) was held in Kuala Lumpur, Malaysia during May 8-9, 2014 The conference provides a platform to discuss Material and Manufacturing Technology etc with participants from all over the world, both from academia and from industry Its success is reflected in the papers received, with participants coming from several countries, allowing a real multinational multicultural exchange of experiences and ideas

The present volumes collect accepted papers and represent an interesting output of this conference This book covers these topics: Advanced Materials Engineering and Processing Technologies, Computing and Information Technology, New Technologies, Methods and Technique in Civil Engineering, and Achievements in Medical and Engineering Sciences

After the peer‐ review process, the submitted papers were selected on the basis of originality, significance, and clarity for the purpose of the conference The selected papers and additional late‐ breaking contributions to be presented as lectures will make an exciting technical program The conference program is extremely rich, featuring high‐ impact presentation We hope that the conference results constituted significant contribution to the knowledge in these up to date scientific field

The proceeding records the fully refereed papers presented at the conference The main conference themes and tracks are Material and Manufacturing Technology etc Hopefully, all participants and other interested readers benefit scientifically from the proceedings and also find it stimulating in the process

This conference can only succeed as a team effort, so the editors want to thank the international scientific committee and the reviewers for their excellent work in reviewing the papers as well as their invaluable input and advice

Dr Meixing Guo

Program Chair

Guizhou University, China

Committees

Honorary Chairs

Prof Adrian OLARU, University Politehnica of Bucharest, Romania

Conference Chairs

Prof Syed Masood, Swinburne University of Technology, Australia

Prof Ahmed A D Sarhan, University of Malaya, Malaysia

Program Chairs

Dr Wasawat Nakkiew, Chiang Mai University, Thailand

Dr M M Emara, Canadian International College(CIC), Egypt

Dr İlhan ASİLTÜRK, Advanced Engineering and Manufacturing Laboratory (AEML), USA

Dr Kyoungjin Kim, Kumoh National Institute of Technology, Korea

Prof Ghenadii Korotcenkov, Gwangju Institute of Science and Technology, Korea

Technical Committees

Dr Pin-Chuan Chen, National Taiwan University of Science & Technology, Taiwan

Dr P SIVAPRAKASH, A S L Pauls College of Engineering& Technology, India Prof Napiah Madzlan, Universiti Teknologi Petronas, Malaysia

Prof Dr Mohammed Jasim Kadhim, Iraq University of Technology, Iraq

Prof Guy Littlefair, Deakin University, Australia

Dr S Narayanan, Senior Professor & Pro-Vice Chancellor, Vellore Institute of Technology, Vellore, India

Prof L C Tsao, National Pingtung University of Science and Technology, Taiwan Prof Seyed Mehdi Rezaei, University of Malaya, Malaysia

Dr Jae Hoon Lee, POSCO Technical Research Laboratories, Korea

Prof Muhammad ANIS, University of Indonesia, INDONESIA

Prof Dr Anika Zafiah Mohd Rus, Universiti Tun Hussein Onn Malaysia, Malaysia Prof Yu SUN, Nanjing Unviersity of Science & Technology, China

Prof Taufik K Aboud, University of Tripoli, Libya

Prof Lou Yan, Shenzhen University, China

Dr Y S Reddy, Chaitanya Bharathi Institute of Technology, India

Dr Koichiro Fukui, Yokohama National University, Japan

Prof Mohsen Abdelnaeim Hassan Mohamed, University of Malaya, Malaysia

Prof Anjaiah Devineni, Manipal University, India

Dr Mum Wai Yip, Tunku Abdul Rahman College, Malaysia

Dr Pongsaton Amornpitoksuk, Prince of Songkla University, Thailand

Dr Sachin Shendokar, College of Engineering, India

Dr Jiraphon Srisertpol, Suranaree University of Technology, Thailand

Dr Yusairie Mohd, Universiti Teknologi Mara, Malaysia

Prof Lung-Chuan Tsao, National Pingtung University of Science and Technology, Taiwan

Prof Anjaiah Devineni, Manipal University, India

Dr Ahmed Sarhan, University of Malaya, Malaysia

Prof Ming-piao Tsai, National Formosa University, Taiwan

Prof Marcus Shaffer, Department of Architecture, Pennsylvania State University, USA

Prof Ho-Sung Lee, Korea Aerospace Research Institute, Korea

Prof TURNAD Lenggo Ginta, UNIVERSITI TEKNOLOGI PETRONAS, MALAYSIA Prof Smit Insiripong, Muban Chombueng Rajabhat University, Thailand

Dr Dhananjay M Kulkarni, Birla Institute of Technology & Science, India

Prof Asif Mahmood, King Saud University (KSU), Saudi Arabia

Dr TAN CHEE-FAI, Universiti Teknikal Malaysia Melaka, Malaysia

Sponsors

Swinburne University of Technology, Australia

Table of Contents

Preface, Committees and Sponsors

Chapter 1: Advanced Materials Engineering and Processing

Effect of Catalyst Concentration on Performance of Hybrid CNT-Carbon Fibre

Nanocomposite

I.S Norazian, A.R Suraya, A Norhafizah, T.M.T Amran and N Alias 15

Membrane

Green Nanoparticle Oil Well Cement from Agro Waste Rice Husk Ash

N Alias, M.M.M Nawang, N.A Ghazali, T.A.T Mohd, S.F.A Manaf, A Sauki, M.Z

A New Double Negative Metamaterial for C-Band Microwave Applications

Sound Absorption Properties of Dwi Matrix Renewable and Synthetic Polymer

Effect of Alkaline Phosphate-Permanganate Conversion Coating on the Corrosion

Resistance of AZ91D Magnesium Alloy

Effect of Calcination Temperature on the Morphology of Carbon Nanosphere Synthesized

from Polymethylmethacrylate

Batteries: A First-Principles Investigation

Condition

Thermal Properties of NiCrSiB Coating on Piston Engine

Material and Structural Engineering of Metal Oxides Aimed for Gas Sensor Applications

Optical and Visible Luminescence Properties

Composite Copolymer Acrylamide/Bacterial Cellulose Hydrogel Synthesis and

Characterization by the Application of Gamma Irradiation

The Characterization of Chitosan-Hyaluronan-Metal Nanocomposites

Uncured Properties of Silica Filled ENR Compounds at High Temperature Curing

Electroless Deposition of Nickel Nanoparticles at Room Temperature

b Material and Manufacturing Technology V

Cysteine Conjugated Gold Nanoparticles and their Scavenging Free Radicals Properties

C.W Chou, J.M Yang, T.S Yang, Y.C Shih, H.H Hsieh, K.H Chang, K.S Chen, W.L Tzu,

Improving the Structural, Optical and Electrical Properties of ITO Nano-Layered Thin

Films by Gas Flow Argon

Q.Z Mehdi, G Hegde, M.A Bin Juusoh, J.B Al-Dabbagh and N.M Ahmed 116

Laser Assisted Machining of Ti10V2Fe3Al and Ti6Cr5Mo5V4Al β Titanium Alloys

R.A Rahman Rashid, S Sun, S Palanisamy and M.S Dargusch 121

Comparison of Endmill Tool Coating Performance during Machining of Ti6Al4V Alloy

S Palanisamy, R.A Rahman Rashid, M Brandt, S Sun and M.S Dargusch 126

Experimental Study of Micro-Milling Microchannels on Polycarbonate Substrates

Tool Life Study of Coated/Uncoated Carbide Inserts during Turning of Ti6Al4V

S Palanisamy, R.A Rahman Rashid, M Brandt and M.S Dargusch 136

Compressive Properties of Solid and Porous Parts Made from High Strength Steel Alloys by

Direct Metal Deposition

Computational Analysis of Single and Multiple Impacts of Low Pressure and High Pressure

Cold Sprayed Aluminum Particles Using SPH

Characterization of Thermal Sprayed Titanium/Hydroxyapatite Composite Coating on

Stainless Steel

Prepared by Mechanochemical Process

Analysis of Roughness and Heat Affected Zone of Steel Plates Obtained by Laser Cutting

The Influence of SS316L Foam Fabrication Parameter Using Powder Metallurgy Route

Effect of Process Parameters in Hot Press Forming Operation to Tensile Strength of Ultra

High Strength Steel

Characterization and Comparison of Thermally Sprayed Hard Coatings as Alternative to

Hard Chrome Plating

Ultimate Elastic Wall Stress (UEWS) Test under Biaxial Loading for Glass-Fibre

Reinforced Epoxy (GRE) Pipes

Processability Behaviour of Dual Filler Systems Reinforced Epoxised Natural Rubber

Microstructure and Hardness of Diffusion Bonded Sialon-AISI 420 Martensitic Stainless

Steel

Simulation of Dirac Tunneling Current of an Armchair Graphene Nanoribbon-Based P-N

Junction Using a Transfer Matrix Method

E Suhendi, R Syariati, F.A Noor, N Kurniasih and Khairurrijal 205

Electrical Coupling of Organic/Inorganic Semiconductor Interfaces: A Comparative Study

M Dhingra, S Shrivastava, P Senthil Kumar and S Annapoorni 210

Performance Analysis of a LTE Band Microstrip Antenna on FR-4 Material

A.U Ahmed, R Azim, T.I Mohammad, M Ismail and M.S Islam 215

Measurement of Liquid Film Thickness around Horizontal Tube Bundle by Optical

Technique for Optimizing Evaporator Design and Manufacturing

Study on Using EDXRF for the Determination of Gold Coating Thickness

Advanced Materials Research Vol 974 c

The Effect of Oxidized White Liquor on Pulp Brightness in Peroxide Bleaching in Pulp

Mills

Rhabdomyosarcoma Cell Line

M Hammad Aziz, M Fatima, M Waseem, M Fakhar-E-Alam, M Afzal and M Nadeem

Evaluation of Mixed Cellulase-Amylase System on Enzymatic Hydrolysis Reaction Using

Response Surface Methodology

Influence of Shear Rate on Proteins Separation, Molecular Weight Cut-Off and Average

Pore Size of Polysulfone Blend Membranes

Characteristics of UV Irradiated Waste Biopolymer from Renewable Resources (Part 1)

Characteristics of UV Irradiated Waste Biopolymer from Renewable Resources (Part 2)

Surface Modified Nano Calcium Oxide for Base Heterogeneous Transesterification of

Kappaphycus Alvarezii Seaweed to Biofuel

Chapter 2: Computing and Information Technology

A New Reinforcement Learning for Train Marshaling with Generalization Capability

Performance Enhancement of 10 Gbps OCDMA Networks Using DPSK and DQPSK with

Unique Code-Sequence

Vehicle Scheduling Model for Fresh Agriculture Products Pickup with Uncertain Demands

Application of Auxiliary Antenna Elements for SAR Reduction in the Human Head

M.I Hossain, R.I.F Mohammad, M.T Islam and N.H.M Hanafi 288

Thinking on the Progressive Failure Analysis of the Slope

The Use of the Six Sigma Approach to Minimize the Defective Rate from Bending Defects in

Hard Disk Drive Media Disks

Extended Supply Chain DEA for Considering Replaceable DMUs

A New Hybrid Model for Forecasting Crude Oil Price and the Techniques in the Model

Analysis of Elastic-Plastic Responses of a Water Tower Structure during an Earthquake

Based on the Transfer Matrix Method of Multibody System

Chapter 3: New Technologies, Methods and Technique in Civil

Engineering

Nanotechnology: The Emerging Field of Civil Engineering Particularly in Developing

Countries

An Experiment on Durability Test (RCPT) of Concrete According to ASTM Standard

Method Using Low-Cost Equipments

Deep Pit Foundation Steel Sheet Pile Supporting Scheme of the 274# Pile Cap for Super

Large Bridge over the Coastal Expressway and the North Jiangsu Irrigation Canal

d Material and Manufacturing Technology V

Effect of LRB Position for Vibration Reduction System of Self-Anchored Cable-Stayed

Suspension Bridge

Investigation of Engineering Properties of Quarry Waste in the East of Thailand for Used as

Fine Aggregate in Concrete

Chapter 4: Achievements in Medical and Engineering Sciences

Step Response Identification for a Batch Reaction Vegetable Oil Transesterification

Analysis of Fuel Injection Parameter on Biodiesel and Diesel Spray Characteristics Using

Common Rail System

A Khalid, A Sapit, M.N Anuar, R Him, B Manshoor, I Zaman and Z Ngali 362

Gas Lift Optimization of an Oil Field in Malaysia

N.A Ghazali, T.A.T Mohd, N Alias, E Yahya, M.Z Shahruddin, A Azizi and A.Y Fazil 367

A New Method for Reconstruction of Corneal Topography with Placido Disk System

Bacterial and Fungal Decolorization of the Remazol Dye in Textile Effluent of Malaysian

Cottage Industries by Lactobacillus delbrueckii and Pleurotus ostreatus

Comparison of Pineapple Leaf and Cassava Peel by Chemical Properties and Morphology

Characterization

Z Daud, H Awang, A.S.M Kassim, M.Z.M Hatta and A.M Aripin 384

The Study of Bone Cutting Force with FEM

Anticandidal Activity of Cratoxylum formosum Gum and its Cytotoxicity

S Thaweboon, B Thaweboon, S Dechkunakorn, P Nisalak and R Kaypetch 394

Auxetic Plates on Auxetic Foundation

A Simple GA Based Approach for Multi-Objective Optimization of Machining Parameters

Optimization of Friction Stir Welding Parameters with Simultaneous Multiple Response

Consideration Using Multi-Objective Taguchi Method

M.A Mohamed, Y.H Manurung, M.R.A Rahim, N Muhammad and F.A Ghazali 408

Determination of Bore Grinding Machine Parameters to Reduce Cycle Time

CHAPTER 1:

Advanced Materials Engineering and Processing

Technologies

Improvement of Mechanical Properties of Al2O3-SiC Composite with

ZrO2 (3Y) Particles

S Watcharamaisakul School of Ceramic Engineering, Institute of Engineering, Suranaree University of Technology 111

University Avenue, Muang District, Nakhon Ratchasima 30000, Thailand

sukasem@sut.ac.th

Abstract The mechanical properties of Al2O3-SiC based composites were improved by the addition of ZrO2(3Y) particles in the range of 10 to 25 vol.% Al2O3-SiC/ZrO2(3Y) composites were manufactured by pressureless sintering at 1550, 1600, and 1650oC Sintered composites were characterized for density, XRD, microstructure and mechanical properties such as flexural strength, fracture toughness and hardness The results showed that the highest flexural strength of 250 MPa was obtained with 25 vol.% ZrO2(3Y) composite sintered at 1600oC due to higher density and smaller Al2O3 grains in comparison with samples sintered at 1550oC and 1650oC, respectively The maximum fracture toughness of 5.66 MPa.m1/2 was obtained with 20 vol.% ZrO2(3Y) sintered at

1600oC The highest hardness of 9.16 GPa was obtained with composite of 10 vol.% ZrO2(3Y) sintered at 1600oC as it contains the largest amount of hard SiC

Introduction

Alumina ceramics (Al2O3) has been widely used as a matrix material because of its good mechanical properties such as high hardness, low electrical conductivity, good chemical stability and oxidation resistance However, the low fracture toughness of Al2O3 limits its use in structural applications Thus, many research studies have focused on improving the mechanical properties of

Al2O3 through the addition of various reinforcing particles such as SiC, ZrO2, TiN/TiC/TiO2, BN and metal particles [1-3] Most of these efforts have made use of SiC particles for reinforcement of

Al2O3 Shi et al [4] studied the effect of SiC amount on mechanical properties of Al2O3-SiC composites The flexural strength of composite was increased with addition of 20 wt% SiC and the

highest fracture toughness was obtained with the sample containing 5 wt% SiC Ko et al [5]

particularly focused their study on the effect of submicrometer SiC reinforced in Al2O3 matrix They showed that SiC can improve flexural strength properties of Al2O3 matrix, while the

toughness properties were less improved Ma et al [6] studied ZrO2 toughening mechanism in

Al2O3 matrix Their results confirmed that ZrO2(2Y) and ZrO2(3Y) could increase the fracture toughness of Al2O3 matrix

The aim of the present work is to investigate the influence of the addition of various amounts of ZrO2(3Y) on mechanical properties of Al2O3-SiC composites such as flexural strength, fracture toughness and hardness

Experimental Procedures

Al2O3 particles (98.50% purity, ACG-2A, Sigma-Aldrich) with a mean size of 3 µm, β-SiC

(Ultrafine, Ibiden Co., Nagoya, Japan) with a mean size of 100 nm and ZrO2 (3Y) with 3 mol%

Y2O3 stabilizer (Hanwha Ceramics Co., Australia) with a mean size of 1 µm were used as starting powders Batch compositions and sintering conditions are summarized in Table 1

Advanced Materials Research Vol 974 (2014) pp 3-8

© (2014) Trans Tech Publications, Switzerland

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Table 1: Batch compositions and sintering conditions

To investigate the effect of zirconia addition on mechanical properties of the composite, the amount of ZrO2 was varied from 10 to 25 vol.% The raw powders of Al2O3, SiC and ZrO2(3Y) were mixed by ball-milling in ethanol for 24 h using Al2O3 balls and a polyethylene jar The mixed slurry was dried and subsequently sieved through a 60 mesh screen to prepare the granulated powder Then, the granulated powder was pressed into a pellet of compacted sample under a pressure of 25 MPa The green bodies were placed in the Al2O3 and graphite protective powder bed

in an alumina crucible and pressureless sintered at 1550, 1600 and 1650oC for 4 h Densities of the sintered specimens were determined by Archimedes method with distilled water as the immersion medium The sintered specimens were ground and polished up to 1 µm, then etched thermally The specimen microstructure was observed using scanning electron microscopy (SEM) The phase identification was carried out by means of X-ray diffraction (XRD) The flexural strength was measured with a three-point bending test [7] The hardness was measured using a Vickers indenter The fracture toughness was determined by the indentation method from Vickers impression marks

Results and Discussion

Microstructure Figure 1 shows SEM micrographs of AS90Z10 sample (90 vol.% (95:5 Al2O3SiC) and 10 vol.% ZrO2) sintered at 1550, 1600, and 1650oC The etched surface observations confirmed that the amount of porosity decreases with increasing sintering temperature and a sample

-of high density is obtained at 1650oC These observations also proved that the zirconia phase is mainly localized at the grain boundaries of Al2O3 The amount of zirconia phase located at the grain boundaries seems to be enhanced by increasing sintering temperature for the composite of the same addition of ZrO2(3Y) powder The presence of ZrO2 phase can prohibit the crack propagation to enhance the fracture toughness of composites [8]

Fig.1: SEM micrographs of AS90Z10 sintered at (a) 1550o (b) 1600oC and (c) 1650oC

Fig 2: SEM micrographs of composites sintered at 1650oC:

(a) AS90Z10, (b) AS85Z15, (c) AS80Z20 and (d) AS75Z25

Figure 2 illustrates SEM micrographs of samples of various amounts of ZrO2(3Y) sintered at

1650oC Microcracks were observed in all samples These microcracks are induced by the compressive stresses around Al2O3 grain boundaries due to the tetragonal (t) to monoclinic (m) phase transformation in ZrO2 at high sintering temperature [7] The higher number of microcracks was detected in the sample containing 25 vol.% ZrO2(3Y) in comparison with samples with less zirconia due to the large amount of phase transformation of t-ZrO2 to m-ZrO2 during cooling down after sintering

Mechanical Properties The flexural strength of sintered composites is illustrated in Fig 3 as a

function of zirconia content The higher flexural strength was obtained with a sample having the smaller amount of zirconia (10 vol.%) and correspondingly the larger amount of high-strength SiC

in comparison with samples of other compositions in the range of 10 to 20 vol.% Therefore, the strength decreased with increasing ZrO2(3Y) addition up to 15 vol.% due to reduction of SiC However, the addition of larger amount of ZrO2(3Y) from 15 vol.% up to 25 vol.% resulted in enhancement of sintered composite strength owing to the formation of large number of microcracks

as a result of phase transformation from t-ZrO2 to m-ZrO2

However, the evaluation of results for samples of the same amount of ZrO2 (25 vol.%) revealed that the highest flexural strength is obtained with samples sintered at 1600oC, while the low density and high porosity of samples sintered at 1550oC leads to their poor mechanical properties The lowest strength of sample sintered at 1650oC could be explained by the excessive Al2O3 grain growth at high temperature The crack path between large grains is less tortuous than that between small grains resulting in high crack growth rate and lower strength

Fig 3: Flexural strength of composite as a function of ZrO2(3Y) content sintered at 1550, 1600, and

1650oC

Figure 4 shows the fracture toughness of composites of various ZrO2 contents sintered at 1550,

1600 and 1650oC The highest fracture toughness of 5.66 MPa.m1/2 was obtained with a composite containing 20 vol.% ZrO2(3Y) and sintered at 1600oC The low density and the large amount of porosity are responsible for the low fracture toughness of samples sintered at 1550oC At the same time, the lowest fracture toughness was obtained with samples sintered at 1650oC due to redundant

Al2O3 grain growth The fracture toughness of composite with 25 vol.% ZrO2(3Y) was lower than that of sample with 20 vol.% ZrO2(3Y) because of the large amount of microcracks [9]

Various toughening mechanisms have been suggested to explain the improved strength of composite materials with dispersed nanoparticles [9] The first toughening mechanisms is due to the dynamic t-m phase transformation toughening effect during fracturing as revealed by X-ray analysis The second is the microcrack toughening effect induced by the volume expansion from the t-m phase transformation during cooling in the final stage of sintering process In addition, ZrO2(3Y) particles can effectively enhance the crack deflection to inhibit further propagation of the

main crack as pointed out by Lin et al.[10]

Fig 4: Fracture toughness of composite as a function of ZrO2(3Y) content sintered at 1550,1600,

and 1650oC

Fig 5: Hardness of composite as a function of ZrO2(3Y) content sintered at 1550, 1600, and 1650oC The Vickers hardness of composite is illustrated in Fig.5 The highest hardness of 9.16 GPa was measured with composite of 10 vol.% ZrO2(3Y) sintered at 1600oC as it contains the largest amount

of SiC which is harder than either alumina or zirconia Therefore, with increasing the amount of ZrO2(3Y) up to 15 vol.%, the hardness decreased due to a decline in quantity of hard SiC Further increase in zirconia content from 15 vol.% up to 25 vol.% resulted in enhancement of hardness due

to the densification of composites

The highest hardness was obtained with sample sintered at 1600oC The low hardness of samples sintered at 1550oC and 1650oC is caused by the low sample density and large amount of porosity at low temperature, and by significant Al2O3 grain growth at high temperature, respectively

Conclusions

The present study has shown that the addition of ZrO2(3Y) particles significantly enhances the mechanical properties of Al2O3-SiC composites The higher flexural strength was obtained with a composite having the smallest amount of zirconia (10 vol.%) and correspondingly the largest amount of high-strength SiC in comparison with composites with 15-20 vol.% ZrO2(3Y) A comparison of samples with the same amount of ZrO2 (25 vol.%) revealed that the highest flexural strength was obtained with samples sintered at 1600oC because they possess higher density than those sintered at 1550oC and smaller Al2O3 grain than samples sintered at 1650oC The highest fracture toughness of 5.66 MPa.m1/2 was achieved with a composite with 20 vol.% ZrO2(3Y) sintered at 1600oC The toughening mechanisms of ZrO2(3Y) particles included the dynamic t-m phase transformation toughening effect during fracturing and the microcrack toughening effect by the volume expansion which comes from the t-m phase transformation during cooling in the sintering process The ZrO2(3Y) particles can also effectively enhance the crack deflection to inhibit further propagation of the main crack The highest hardness of 9.16 GPa was measured with composite of 10 vol.% ZrO2(3Y) sintered at 1600oC as it contains the largest amount of hard SiC

[2] H.Z Wang, L Gao and J.K Guo: J.Euro.Ceram.Soc., Vol.19 (1999) p.2125-2131

[3] P.C Enrique, R.R Enrique and R.R Mario: J Ceram Process Res.Vol.11(3) (2010), p.372-376 [4] X.L Shi, F.M Xu, Z.J Zhang, Y Tan, L Wang and J.M Yang: Mater Sci Eng Vol.A527 (2010), p.4646-4649

[5] Y.M Ko, W.T Kwon and Y.W Kim: Ceram Int Vol.30 (2004), p.2081-2086

[6] W Ma Lei, W Renguo, G Xudong and L Xikun: Mater Sci Eng Vol.A477 (2008), p.100-106 [7] L Gao, H.Z Wang, J.S Hong, H Miyamoto, K Miyamoto, Y Nishikawa and A.D.D.L.Torre: Nanostruct Mater Vol.11(1) (1999), p.43-49

[8] W.H TuanChen, R.Z Wang, T.C Cheng, and P.S Kuo: J Euro Ceram Soc Vol.22 (2002), p.2827-2833

[9] H Awaji, S.M Choi and E.Yagi: Mechanics.Mater Vol.34 (2002), p.411–422

[10] G.Y Lin and T.C Lei: Ceram Int Vol.24(1998), p.313-326

Prediction of Long – Term Creep Properties of Kenaf Fiber Unsaturated

Polyester Composites

Saad A, Mutasher1,a and Ekhlas A Osman2,b1

Ministry of Higher Education, College of Applied Sciences, Engineering Department, Sohar, P O

Box 135, Post code 133, Sultanate of Oman 2

Swinburne University of Technology, Sarawak Campus, Faculty of Engineering, Jalan Simpang

Tiga, Kuching, Sarawak, Malaysia a

saadj.soh@cas.edu.om, saadassi@gmail.com, b ekhlas_aboud@yahoo.com

Keywords: kenaf fiber, creep test, frindely’s law, natural fiber composite

Abstract This research focuses on predicting long-term behavior of unsaturated polyester resin

(UP) and kenaf unsaturated polyester composite The objectives of these tests are to establish a relationship between stress, strain and time at constant loading and temperature The results obtained from these tests are used in predicting the life and strength of the polymer material Based

on the 1,000 hours experimental data, curve fitting and Findley Power Law models are employed to predict long-term behavior of the material The results showed that curve fitting model accurately predicted the non-linear time dependent creep deformation of these materials with acceptable

accuracy

Introduction

Rapid developments of technology in every sector have been very advantageous, but the acts of human being have caused adverse effects on the environment The adverse effects of today’s development are such as depletion of ozone layer, greenhouse effect, global warming, pollutions, reduction in natural resources etc Natural fiber/polymer composites (NFPCs) are being increasingly used in construction and their creep behaviors under constant stress are receiving more research interest There have been many studies done around the world to prove that kenaf can be used to produce kenaf-based composites with acceptable physical and mechanical properties Creep is one

of the principal properties of natural fibers reinforced polymer composites and it is of great importance to understand the creep behavior for many applications such as aerospace, biomedical and civil engineering The application of NFPC in construction raised the requirements of their mechanical properties, especially their creep resistance under constant stress that commonly exists

in structural building products Creep is deformation of material under constant stress, dependent on time, stress, temperature, and material properties, etc Creep deformation can exceed the creep limit and cause product failure, especially in applications with long-term loading Understanding, evaluation and prediction of creep behavior of NFPC are thus of great importance for its application [1] One of the most important techniques for creep characterization is modeling The 4-element Burgers model was widely adopted to characterize the viscoelastic behavior of the materials [2-4] Findley's power law model [5] and a simpler two-parameter power law model [6] were also attempted to simulate the creep curves of NFPCs Time-temperature superposition (TTS) was tried

to predict long-term creep deformation of NFPCs from the accelerated testing data at different temperature levels and smooth master curves were obtained Some NFPCs, however, have been shown to be thermorheologically complex and TTS cannot be applied to predict their long-term creep curves through a single horizontal shift [6] Kanchwala, 2010, [8] studied the long-term behavior of polyurea composite The results obtained from these tests were used in predicting the life and strength of the polyurea material

This article focuses on measuring flexural strain test under constant load for short treated kenaf bast fiber reinforced unsaturated polyester composites The experiment was setup for 1000 hours

Advanced Materials Research Vol 974 (2014) pp 9-14

© (2014) Trans Tech Publications, Switzerland

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Curve fitting and Findley Power Law models were employed to predict long-term behavior of the kenaf composites

Composites Fabrication

A compression moulding process was used for fabrication process Specimens with 20% weight percentage of fibers were fabricated to produce kenaf/unsaturated polyester composites The prepared resin (60%UP+ 40%ST) + 1% Methyl ethyl ketone peroxide (MEKP) were blended to fiber size (1-6) mm to prepare the composites Composite mixture was poured in the mold cavities The mixture is gently pressed using fingers to make sure the cavity of mould is properly filled Composites were left few minutes allowed air bubbles to escape from the surface of resin The top plate was putted in place and mixture was left to relax for 10 min Top plate was screwed tightly in place Composite was left to cure for about 24 hours at 25±2 ºC The specimens are grinded to trim the flushes of resin during fabrication process Certain composites specimens were post cured in an oven for 5 hours at 60 ºC

Flexure Creep Test

The apparatus designed for conducting the flexural creep test was custom fabricated and used a simple loading mechanism at room temperature The test frame was designed using mild steel angle frames of (50 x 50) mm machine welded The apparatus has been designed to accommodate multiple specimens for more than one specimen at a time For the flexural test, the frame was custom fabricated with rods were rested and bolted on the groove of the frame to allow bending specimen to lie over and maintain 100 mm distance The dial gauge was clamped magnetically, calibrated to zero and tip of dial gauge was rested on the center of specimen, as shown in Figure 1

A three point bending test was setup and deflection was measured with respect to time The weight

is calculated based on 15% of maximum flexural strength; the weight hung with the support of hook, where the hook tied with the cotton thread to allowing it to hang vertically with the specimen From previous work of the authors for 20wt% of kenaf composite the flexural modulus and flexural strength are 4 GPa and 69.9 MPa, respectively

Figure 1 Setup of flexural creep test

Results and Discussion

Theoretical Models

Log Curve Fitting Analysis Model: Curve fitting method is used to analysis and extrapolates the

creep results For most of the polymer materials, the design life can be quite long period The log method is used to predict the design life of the material which will tend to display linearly on the log-log coordinated

log-C x B x A

(1) Considering x and y coordinates as log Therefore, y = log ε and x = log t Consequently Equation 1 becomes

( )

[Log ε ]2=A[Log( )t ]2+B Log( )t +C (2) where, ε is creep strain at constant load, t time in hour, A,B and C are coefficient depended on the load, material, loading conditions Since ε is less than 1, a negative solution of the Equation has to

be selected to find the strain [7]

( ) A[Log( )t] B Log( )t C Logε = − 2+ + (3) Since the analysis was based on 1000 hours, three points of test were selected for each experimental strain as time t1 = 20 second (initial time), time, t2 = 500 hours and time t3= 1000 hours Such times are needed to take to ensure the model covers all the range of experimental data and gives a prediction of theoretical behavior Table 1 shows the values of the parameters at t1= 20 sec, t2 = 500 hours and t3 = 1000 hours which are obtained from the experimental data for unsaturated polyester resin When t = 1 hr Equation 2 becomes;

ο

σ

σε

σ

σε

(7) The equation has a time-dependent part, and involves five material constants It is difficult to

find the Findley’s constants, therefore for small stresses, sinh(σ/σ ο ) term becomes (σ/σ ο ) and in this

case the Findley’s equation reduces to [8]

ο

σ

(8) Since, the experimental data is only available for 1000 hours the predicted strain for 50-year design life is highly variable In order to extrapolate for 400,000 hours more data is required However, an attempt is made to predict the 50-year strain based on 1000 hours results The Findley’s power law is given as

t m

where, ε t strain at any time, ε ο initial strain, m dependent coefficient, n independent material constant, t time after loading (hours) Constants m and n are needed to formulate the power law

were evaluated using the experimental creep data obtained and plotting logarithmic graph Using Equation 9 and taking log on both sides we get:

( ( ) ( )t Log( )m n Log( )t

Theoretical Strain of Unsaturated Polyester Matrix Using Findley’s Model

To obtain the constants m and n for unsaturated polyester, log-log graph was plotted to obtain a straight line plot Plotting the creep strain data on a log-log scale for log (ε(t)−(εo) on y-axis and time on x-axis as shown in Figure 2 Then using y = mx +c, vertical intercept gives m and the slope

of the line will give n constant The summary of constants m and n for the matrix and kenaf

composites are shown in Table 3

Figure 2 Log strain vs time for the constant m and n for unsaturated polyester

Table 3 Constant m and n for all the specimens

Specimen Constant- m Constant- n

Experimental and Theoretical Strain

Flexural Creep Results for Unsaturated Polyester Resin

Figure 3 presented the creep strain for unsaturated polyester specimen under bending loading The experimental results at initial creep strain decreases showing primary region of creep, then followed by constant creep rate at secondary stage and at the end of 1000 hour strain rate goes towards to be constant The maximum strain reached at the end of 1000 hours is 0.111933.In the comparison with the theoretical strain; log curve analysis predicts better results than Findlay’s model

The effect of treated kenaf short fiber on flexural modulus of unsaturated polyester resin is illuminated in Figure 4 The interface between the kenaf fiber and resin improve the flexural modulus of the resin, this interfacing change the structure of the resin by increasing the toughness

of materials, which means the matrix become more rigid material The low modulus of resin material limits its potential for structural applications This situation further aggravated by the reduction in this modulus with increase in time of loading For that reason, the design of polymer material is controlled by stiffness rather than by strength [7]

y = 0.2445x - 2.7545

R 2

= 0.9399

-3 -2.5 -2 -1.5 -1

Figure 3 Flexural creep strains, experimentally and theoretically for unsaturated polyester resin

Figure 4 Effects of kenaf fiber on flexural creep strains for unsaturated polyester resin

Flexural Creep Results of Kenaf Unsaturated Polyester Composite

Figure 5 presented the comparison of experimental and theoretical strain of Kenaf fiber unsaturated polyester composite under bending loading It observed that the log curve gives a better fit with the experimental strain Findley’s model started deviating away after 300 hours Generally the strain rate increases rapidly in the primary region for composite, after certain hours strain rate gets constant At the end of 1000 hours it is noted that strain rate remain constant suggesting, the experiment can be tested carried more until the necking takes place

Figure 5 Flexural creep strains, experimentally and theoretically for kenaf composites

0 0.02 0.04 0.06 0.08 0.1 0.12

0 1000 2000 3000 4000 5000 6000

Conclusions

This study developed an understanding of long-term behavior of unsaturated polyester and kenaf unsaturated polyester composites under tensile and flexural loading Predictions accessible are formulated using both the general form of Findley’s Power Law as well as the log curve fitting method The results showed that the insertion of kenaf fiber as reinforce in unsaturated polyester composite is improved the creep properties The obtained creep data were in good agreement with Findley’s Power law The long term creep properties of kenaf unsaturated polyester composites is predicted and extrapolating to 50-year

[4] B A Acha, M M Reboredo, and N E Marcovich, “Creep And Dynamic Mechanical Behavior Of PP-Jute Composites: Effect Of The Interfacial Adhesion,” Composites Part A, 38,

pp 1507-1516, 2007

[5] W N Findley, S N Lai, and K Onaran, “Creep And Relaxation Of Nonlinear Viscoelastic Materials, With an Introduction to Linear Viscoelasticity,” Dover Publications, NY, 1989 [6] M Tajvidi, R H Falk, and J C Hermanson,”Time-Temperature Superposition Principle Applied to a Kenaf-Fiber/High-Density Polyethylene Composite,” J Appl Polym Sci., 97, pp 1995-2004, 2005

[7] M Z Kanchwala, “Testing & design life modeling of Polyurea Liners for Potable Water Pipes,” MsC Thesis, the University of Texas at Arlington May 2010

[8] H Lin, “Creep Charaterization of CIPP Material under Tension, Compression and Bending, M.S Thesis, Lousiana Tech University, LA, 1995

Effect of Catalyst Concentration on Performance of Hybrid CNT-Carbon

Fibre Nanocomposite

I.S Norazian1, a, A.R Suraya2,b , A Norhafizah3,c, T.M.T Amran4,d

and N Alias5,e 1,4,5

Faculty of Chemical Engineering, Universiti Teknologi MARA, 40450 Shah Alam, Selangor,

Malaysia 2,3

Faculty of Chemical and Environmental Engineering, Universiti Putra Malaysia, 43400 Serdang,

Selangor, Malaysia a

azian83@salam.uitm.edu.my, bsuraya@eng.upm.edu.my, cfizah@eng.upm.edu.my,

amran865@salam.uitm.edu.my, nurhashimah@salam.uitm.edu.my

Keywords: Floating catalyst CVD, coated carbon fiber, TEM, EDX spectrum, hybrid

nanocomposites, tensile modulus

Abstract In this research, the CNT coating treatment process involves the growth of CNTs onto the

surface of the carbon fibre by floating catalyst techniques using CVD The amount of ferrocene

concentration has been varied throughout this study Different morphologies of structured CNTs

through TEM instruments are discussed and the analysis study of the composition of the coated

carbon fibres by the growth of CNTs using EDX is also explained In the present study, various

ferrocene concentration gives a greatest influenced to the structure of CNT growth on carbon fibre

surface Lower ferrocene concentration favoured the growth of CNTs meanwhile higher catalyst

amount lead to catalyst poisoning effect which resulting lower tensile strength of the hybrid

CNT-carbon fibre nanocomposite structure

Introduction

A structure of high performance fibre nanocomposite materials requires a remarkable collaboration

between the fibrous fillers and the matrix The adhesion of the fibre with the matrix is very crucial to

determine the mechanical properties of the composites Carbon fibres, for example, despite of its

lightweight properties, it shows a significant weak cohesive behavior when reinforced with polymer

matrix in composite, due to their smooth surface and chemical inertness Therefore, carbon fibres

have to be treated to increase the surface areas to enhance the surface wettability, thus providing a

strong binding with the matrix Nowadays, the direct growth of CNTs on surface of carbon fibres

during the surface treatment process has attracted interest among the researchers as the combination

of both materials promised a super strong mechanical property for hybrid nanocomposite

There are various catalyst normally used as supports in supported catalyst CVD [1] The growth of

CNTs on surface of carbon fibres via floating catalyst techniques using CVD has been carried out in

this research with the presence of ferrocene as the catalyst precursor The presence of ferrocene as

nanoparticles may enhance the soot nucleation, thus increasing the sooting tendency The catalyst

will decompose to provide the iron catalyst particles required for the nucleation of nanotubes [2]

Furthermore, the growth and features of CNTs on surface of carbon fibres are very much dependent

on the environmental conditions of the growth systems which include the concentration of the

catalyst precursor Therefore, the present work describes different morphology of CNTs synthesized

on surface of carbon fibres due to different catalyst concentration exerted to the growth systems This

work also presents some preliminary results on the mechanical properties of hybrid CNT-carbon fibre

nanocomposites

Advanced Materials Research Vol 974 (2014) pp 15-19

© (2014) Trans Tech Publications, Switzerland

doi:10.4028/www.scientific.net/AMR.974.15

Experimental Method

Surface treatment Benzene was used as the carbon source meanwhile ferrocene as the catalyst

compound Three different ferrocene concentrations were used as listed in Figure 1 Ferrocene and the strands of carbon fibres were initially placed inside the CVD furnace The furnace was simultaneously heated until 800oC within an argon atmosphere preceding furnace purging During heating, ferrocene is gradually heated and vapourized at 120oC Hydrogen gas was used to bubble out the benzene at 100 ml/min The vapourized benzene and ferrocene were passed together into the heart

of the furnace for the reaction process to take place in 30 minutes Then, the furnace was let to cool down to room temperature under argon gas SEM and EDX analysis was done to observe the morphology and to analyze the chemical composition of the CNTs produced on the carbon fibre surface prior to fabrication of carbon fibre nanocomposites

Fabrication of nanocomposites In making the hybrid CNT-carbon fibre nanocomposites, a

polypropylene (PP) polymer was used as a matrix to be incorporated with the carbon fibre Initially, the samples of carbon fibre were melt blended with a PP matrix by using an internal mixer Thermo Haake PolyDrive with a Rheomix R600/610 The compounded composites were then processed to form a sheet of composite through hot compression moulding The compression temperature was set

at 170oC which was similar temperature to melt the PP matrix The sheet was removed from the mould and ready to be cut into a dumb bell shape with a specific size following the ASTM D-638 requirement for tensile test specimens

Results and Discussions

Surface morphology Figure 1 represent the CNTs produced via floating catalyst technique at

800oC At the same magnification, the structure of the CNT coated carbon fibre growth at different ferrocene concentration was found to be quite different Figure 1(a) and (b) indicates that the surface

of carbon fibre was covered with CNTs However, one can see that the layer of the carbon fibre surface was not fully utilized by the growth of CNTs and the CNTs tend to grow with the existence of impurities This can be indicated by clumpy structures for all figures These impurities present most likely due to highest temperature used in reaction where little growth of CNTs is observed when the reaction temperature is fixed at 800oC [3]

It can be observed that the amount of CNTs produced tends to decrease with an increase of ferrocene concentration It was seen that less CNTs were formed especially when using 1.0g ferrocene It was also observed that the carbonaceous impurities tended to appear together with the CNTs with increasing ferrocene concentration The increased of ferrocene amount results more Fe clusters in the furnace that can disrupt the surfaces of the already grown aligned CNTs The formation

of new Fe clusters may become the new points for carbon to nucleate and grow into new CNTs, which introduces many nanolumps and branches on the already grown aligned CNTs [4] Furthermore, the increase in Fe concentration increased the probability of particle growth The short SWNTs associated with much larger diameter Fe nanoparticles suggests that SWNT growth began but was rapidly terminated by continued Fe atom condensation on the active catalyst nanoparticles Therefore, high ferrocene concentrations, however, may lead to particle growth occurring too rapidly, preventing even SWNT inception altogether [5] Thus, the yield of CNTs seems to be decreasing in accordance to increasing concentration Besides, the number of active sites for nucleation was reduced at the higher deposition temperature, i.e at 800oC which was mainly caused by the agglomerated of catalyst particles [6] Therefore the yield of CNTs tended to be remarkably reduced

as evident from Figures 1(a) until (c)

concentration

Chemical composition In order to verify the existence and the chemical composition of the amount

of iron Fe in the formation of CNTs, the CNT-coated carbon fibres were examined using EDX Figure

1 also represents the EDX spectrum obtained from the sample which has been deduced in Table 1

Table 1: Chemical composition of CNT coated carbon fibre

When the ferrocene concentration was increased, Fe particles which were released through decomposition to perform the support for the CNTs to grow, also increased This can be seen through the EDX spectrum in Figure 1 where the peak of the Fe particles increased accordingly with the amount of ferrocene concentration In these figures, the peak of Fe in Figure 1(c) indicates the highest peak of Fe Therefore, it can be said that the clumpy structures indicated in Figure 1(c) was consists of metal impurities due to the agglomerated Fe particles during the synthesis of CNTs The Fe particles used to initiate the CNT nucleation process seem to be growth and agglomerated to each other to a size where the CNTs could not be form The agglomerated Fe particles tend to deposit on the surface

of the carbon fibre without making a support for CNTs to grow

Tensile strength The CNT-carbon fibre reinforced polypropylene (CF/PP) composites were

compared with the uncoated CF/PP composites The tensile strength as well as the enhancement over the neat CF/PP composites is listed in Table 2 It shows that the uncoated CF/PP composite exhibited tensile strength of 20 MPa The surface without the formation of CNT did not give a strong bond with the matrix during the fabrication of the uncoated CF/PP composite However, the growth of CNT on surface of carbon fibre able to provide higher surface wettability, thus able to improve the adhesion with the PP matrix which resulting significant increment in tensile strength values up to 27% It is also shown that the tensile strength value is decreased with increasingly ferrocene concentration This

is most likely occurred due to the existence of the clumpy structures consist of carbonaceous inclusions as shown in Figure 1 The increased of ferrocene weight used may lead to catalyst poisoning during CNT growth which caused the carbon fibre to agglomerate and not well dispersed into composites The presence of carbonaceous impurities affected the potential adhesion between the carbon fibre and the matrix

Table 2: Tensile Strength of hybrid CNT carbon fibre nanocomposite

Catalyst

Percentage of increment Untreated carbon

Acknowledgements

The work was supported by Ministry of Science and Technology (MOSTI), Malaysia under the eScienceFund grant (Project No: 03-01-04-SF0795) The authors also would like to acknowledge the financial support provided by Universiti Teknologi MARA under the 600-RMI/RAGS 5/3 (65/2012)

A part of this work is also supported by Research Interest Faculty (RIF) grant (600-RMI/DANA 5/3/RIF (134/2012)

References

[1] Mark H.R, Alicja B, Felix B, Franziska S, Imad I, Krzysztof C, Grazyna S, Daniela P, Ewa

B, Gianaurelio C, Bernd B Synthesis of carbon nanotubes with and without catalyst particles

Nanoscale Research Letters Vol 6 (2011), p 303

[2] K Kazunori, S Kozo Modeling ferrocene reactions and iron nanoparticle formation: Application to CVD synthesis of carbon nanotubes Proceedings of the Combustion Institute Vol 31 (2007), p 1857-1864

[3] M.J Bronikowski CVD growth of carbon nanotube bundle arrays Carbon Vol 44 (2006), p

2822–2832

[4] X Bai, D Li, Y Wang, J Liang Effects of temperature and catalyst concentration on the growth

of aligned carbon nanotubes Tsinghua Science and Technology Vol 10 (2005), p 729 – 735 [5] L Randall, J.H Lee Ferrocene as a precursor reagent for metal-catalyzed carbon nanotubes: competing effects Combustion and Flame Vol 130 (2002), p 27-36

[6] A Moisala, A.G Nasibulin, E.I Kauppinen, The role of metal nanoparticles in the catalytic production of single walled carbon nanotubes – A review Journal of Physics Condensed Matter Vol 15 (2003), p S3011-S3035

Electrophoretic Deposition of Titanium Dioxide (TiO2) Nanoparticles on

suspension, zeta potential

Abstract: The purpose of this study is to understand the electrophoresis of Titanium dioxide (TiO2) nanoparticles on ceramic membrane The ceramic substrate was prepared using commercial ceramic filter The effect of different types of solvent used for suspension was studied Then, the solvent that give optimum formulation for deposited microstructure on ceramic electrode from the first stage experiment is used to study the effect of concentration on the deposition behavior of TiO2nanoparticles during EPD technique All the TiO2 suspension were had been characterized using Zetasizer Nano series The EPD was performed at 20 V DC field for 10 minutes The deposited of TiO2 from both stage of experiment were then analyzed using ESEM The suspension in organic solvent was found to obtain more deposited particles on ceramic membrane compared to water-based suspension While, the concentration with 0.5 wt % TiO2 nanoparticles with zeta potential 53.6 mV was found to get smaller size and uniform microstructure The adhesion of the TiO2 deposited layer

from entire of the result on the ceramic electrode was fairly good

Introduction

Titanium dioxide (TiO2) is important material for electrochemical, catalytic, electronic, paint and biochemical application, and air purification [8-9] Nowadays, TiO2 has been utilized to prepare various type types of nanomaterials due its photocatalytic properties [3] EPD is a colloidal process which the motions of charged particles in a stable suspension move under the influence of electric field toward an electrode of the opposite charge [7] EPD technique offers many processing advantages for the deposition of TiO2 films such as high deposition rate, low cost of equipment, short formation time, and possibility to deposit on complex substrate [1] In the EPD process, the deposited microstructure is depending on process parameters such as applied voltage, deposition time, suspension composition and surface modifying additives[2] Among this parameter, suspension formulation is regarded as a key parameter affecting the deposition quality [3]

Recently nonmetallic solid has been increasing interested to be use instead of metal substrate Dor

et al and Sadeghi et al had been deposited TiO2 on glass substrate [4, 8] On the other studies by

Kreethawate et al was used porous ceramic tube to obtain polypyrrole (Ppy) coating [7] The

different substrates give the different results on adhesion strength of particles to the substrate Thus,

in order to control of film characteristics the deposition factor such as choose the suitable solvent media and formulation of stable suspension is important to ensure high electrophoretic mobility and

to control porosity, thickness of film and control the defect on electrodeposition image [1] The effect between the used of aqueous and non aqueous for TiO2 suspension used for TiO2 nanoparticles suspension is investigate for EPD application on ceramic electrode Then, the second goal of this study is to investigate the effect of concentration of the TiO2 suspension to the surface morphology on the ceramic membrane surface by ESEM

Methodology

The experimental work of this project consists of two stages The first stage was to study the effect of the different types of solvent used for preparation of TiO2 nanoparticles suspension Two components for TiO2 suspension was varied by using organic solvent and water, respectively After that, the

Advanced Materials Research Vol 974 (2014) pp 20-25

© (2014) Trans Tech Publications, Switzerland

doi:10.4028/www.scientific.net/AMR.974.20

second stage of experimental work was run to investigate the effect of concentration of suspension to the morphology and deposition yield on the ceramic membrane surface

Preparation of 0.1 wt % TiO 2 suspension Aqueous suspension was prepared by mixing 0.15 g

TiO2 (Degusa 25) with 150 ml deionised water 0.4 ml acetylacetone were added as additive to improve stability of suspension Mixtures were then magnetically stirred for approximately 24 hour After that, the suspension of TiO2 was homogenized by ultrasonicater in water bath for 30 minutes at room temperature For non- aqueous suspension, TiO2 suspension was prepared by mixing 0.21 g of TiO2 with 150 ml ethanol and 0.4 ml acetylacetone and covered with aluminium foil to avoid suspension from evaporated [4] Mixtures were then magnetically stirred for approximately 24 hour before added with charging solution Charging solution been prepared by mixing 4 ml of acetone with 2ml of de-ionised water and 27 mg of iodine powder dissolved in 100 ml of ethanol [5] The suspension then was homogenized for 30 minutes by ultrasonicater in water bath model Elmasonic S 180H Suspension parameters of particle size in suspension and the surface charge condition on the

surface of the suspended particles was analyzed using Nano Zetasizer Series Instrument

Electrophoretic deposition (EPD) of TiO2 suspension The ceramic electrode were prepared using

commercial ceramic filter Ceramic substrate were prepared by cutting with a standard dimension of 1.5 mm width, 5mm length and 25 mm height Then, its been treated in a pretreatment stage by using acetone and mild soap Prior before EPD, prepared ceramic substrates were been weighted At the end, the treated substrates were then submerged into the prepared media by a distance of 25 mm distance EPD set-up with a constant DC voltage of 20V was applied for 10 minutes of deposition time using an in-house built circuit The applied voltage was maintained during the slow extraction of the working electrode from the suspension to minimize coating removal Electrical contact to the electrodes was made according to experimental set-up shown in Figure 1 After EPD, the deposited substrates were dried using Venticell dryer at 60°C for 24 hours The morphology of dried deposit particles for each substrate was characterized by using Environmental Scanning Electron Microscopy

(ESEM)

Fig 1: EPD set-up

Preparation of 0.1, 0.5 and 1.0 wt % TiO 2 in ethanol suspension

0.1 wt%, 0.5 wt% and 1.0 wt% of the TiO2 powder in the ethanol solution were prepared by followed non-aquoues preparation procedures EPD with a constant DC voltage of 20V was applied for 10 min

of deposition time using an in-house built circuit The morphology of deposite microstructure was characterized by using ESEM The results from ESEM were compared

Result and Discussion

The effects of different types of solvent The zeta potential and average particles size obtained from

the analysis was summarizing in Table 1 is based on result obtained for different types of solvent in Fig 2 The zeta potential value is -21.2 mV for water suspension The negatively charged of TiO2

suspensions will migrate toward the electrode of opposite charge which is at anode [4] Therefore, the anodic depositions tend to occurred From Table 3, the deposition of electrode in water suspension

has a significant increased in weight in anode electrode The increasing of weight is too slightly at electrode cathode which almost zero

While, the zeta potential value in ethanol suspension as shown in Fig.2(c) is 23.7 mV The positive value indicates that the sample is in acidic This suspension condition will contribute to the adsorption

of the H+ ions onto the particle surfaces which improves the electrostatic repulsion force [5] The weight of deposited TiO2 at electrode cathode is more significant As comparing result in Table 3, the deposition yield is higher in organic suspension But the increasing of weight for both suspensions is too slightly From Fig.2 (b) and 2(d), there are only slightly different in size for both suspensions However, in comparison, the organic suspension result in smaller size compared to water suspension The obvious different effect both suspensions is the direction potential at different electrode which water suspension tends to deposit at anode electrode since obtained negative zeta potential value and cathode deposition for ethanol suspension

organic suspension Although the use of water-based suspensions has economical and environmental advantages over the use of organic solvent, but the quality the deposited surface is affected [10]

Fig.3: The microstructure of the deposited TiO2 in different type of suspension: (a) water, and (b)

ethanol suspension

The effects of TiO2 concentration From the Table 2, all positive zeta potential values obtained

indicate that the samples will be deposited at cathode cell The higher positive zeta potential is at concentration 0.5 wt % and increasing the concentration tends to increase the particle size The suspension with 1.0 wt % has the smallest zeta potential The attraction exceeds repulsion for low zeta potential suspension Therefore, the dispersion will break and flocculate to form bigger particles which are 1837 nm In other words, the suspension in higher concentration was not stable due to higher tendency for flocculation [3]

Table 2: Summary of suspension parameters measured at different concentration based on Fig.2

to deposit to the cathode is one of the reason to the slightly increased to the electrode cathode weight Fig.4(b) shows a more homogeneous and uniform microstructure on the ceramic substrate 0.5 wt % concentration The size of particles is smaller At higher concentration, the formation of nonuniform particle in the deposited TiO2 is shown in Fig.4(c) At higher concentration, the microstructure was seen bigger and non uniform in size The particles were aggregated to produce bigger particles as the concentration of particles is increased [6] Analysis from fig.4 shows that the best deposited microstructure to occur is at 0.5 wt %

The results indicate that the suspension is in stable condition Increasing the concentration was increased the amount of TiO2 deposited and formation of agglomerates Particle tends to agglomerate

at higher concentration Therefore, the concentration is important consideration for improved the stability of suspension for EPD as it will give a significant result

(a)

Fig 4 : The microstructure of the deposited TiO2 at different concentration : (a) 0.1 wt % ,( b) 0.5 wt

% , and (c) 1.0 wt % in ethanol suspension

The types of solvent give a significant effect towards the deposition of TiO2 particles on ceramic substrate The potential for deposition electrode varies with types of solvent used For water-based suspension, the anodic EPD tend to occur while for suspension in ethanol shows the deposition at cathode electrode Positive and negative zeta potential values give the initial indicator for the deposition types The suspension in organic solvent was found to obtain more deposited particles on ceramic membrane compared to water-based suspension Future works was recommend to improved the stability of TiO2 suspension by using poly(acrylic) acid (PAA) in aqueous suspension for better deposition in aqueous suspension [8].For the effect of concentration, higher concentration tends to produce bigger particles and agglomerates [4] Too lower zeta potential value tends to contribute to unstable suspension where the suspensions easily flocculate 0.5 wt% can be conclude as optimum concentration for deposition of TiO2 on ceramic electrode which obtained more uniform microstructure surface

Acknowledgements

The authors would like to acknowledge Universiti Teknologi MARA for Research Intensive Faculty (RIF) Project number 600-RMI/DANA 5/3/RIF (317/2012) for the financial support to carry out this research Authors also, thankful to the staff of Faculty of Pharmacy, Universiti Teknologi MARA, Puncak Alam for their help in FESEM-EDS and TEM analysis

References

[1] Besra, L and Liu, M (2007) A review on fundamentals and applications of electrophoretic

deposition (EPD) Progress in Materials Science 52(1): 1-61

[2] Chavez-Valdez, A and Boccaccini, A.R (2012) Innovations in electrophoretic deposition:

Alternating current and pulsed direct current methods Electrochimica Acta 65(0): 70-89

[3] Corni, I., M P Ryan, et al (2008) Electrophoretic deposition: From traditional ceramics to

[4] Dor, S., S Rühle, et al (2009) The influence of suspension composition and deposition mode on the electrophoretic deposition of TiO2 nanoparticle agglomerates Colloids and Surfaces: Physicochemical and Engineering Aspects 342: 70-75

[5] Grinis, et al (2008) Electrophoretic deposition and compression of titania nanoparticle films for dye-sensitized solar cells Journal of Photochemistry and Photobiology 198 :52–59 [6] Hyam, R S., Subhedar, K M et al (2008) Effect of particle size distribution and zetapotential

on the electrophoretic deposition of boron films Colloids and Surfaces A:Physicochemical and Engineering Aspects 315: 61-65

[7] Kreethawate, L., S Larpkiattaworn, et al (2010) Application of electrophoretic deposition for inner surface coating of porous ceramic tubes Surface and Coatings Technology 205(7): 1922-1928

[8] Sadeghi, A A., T Ebadzadeh, et al (2013) Electrophoretic deposition of TiO2

nanoparticles in viscous alcoholic media Ceramics International p.1-6

[9] Sun, Y., M S Ata, et al (2012) Electrophoretic deposition of TiO2 nanoparticles using

organic dyes Journal of Colloid and Interface Science 369(1): 395-401

[10] Yoshioka, T., A Chavez-Valdez, et al AC electrophoretic deposition of organic-inorganic composite coatings Journal of Colloid and Interface Science 392(0): 167-171

Green Nanoparticle Oil Well Cement from Agro Waste Rice Husk Ash

N ALIAS1, a, M.M.M NAWANG1,b , N.A GHAZALI1,c , T.A.T Mohd1,d, S.F.A Manaf1,e, A Sauki1,f, M.Z Shahruddin1,g and N.A Ramlee1,h

1Faculty of Chemical Engineering, Universiti Teknologi Mara, 40500 Shah Alam, Selangor, Malaysia

anurhashimah@salam.uitm.edu.my, bmdmuslim.nawang@gmail.com

cnurulaimi@salam.uitm.edu.my, damran865@salam.uitm.edu.my,

eshareenafairuz@salam.uitm.edu.my, farina_sauki@salam.uitm.edu.my,

gmunawar_zaman@salam.uitm.edu.my and hazrini@salam.uitm.edu.my

Keywords: Nanosilica, Rice husk ash, Porosity, Compressive strength, Green nanoparticle

Abstract Cement is an important part in oil and gas well completion A high quality of cement is

required to seal hydraulic pressure between casing and borehole formation Cement additives were used to enhance the cement properties such as thickening time, compressive strength, porosity and permeability of the cement Currently, the commercial additives were imported and the price is keep increasing year by year Therefore, the researchers were continuously looking for potential additives such as nanoparticle to improve the cement properties This paper presents the effect nanosilica on compressive strength and porosity of oil well cement type G In this study, two type of nanosilica were used, synthesis nanosilica from rice husk ash (RHA) and commercial nanosilica The synthesized nanosilica was characterized using fourier transform infrared spectroscopy (FTIR), X-ray flouresece (XRF) and Field Emission Scanning Electron Microscopy (FESEM) All the experiments were conducted using API standard procedures and specifications Based on the results, compressive strength of cement slurries was improved from 2600 psi to 2800 psi for 8-hours curing, when the amount of nanosilica increased from 0 wt% to 1.5 wt% Besides that, incorporation of nanosilica from RHA into cement formulation resulted in reduction of cement porosity up to 18 % pore volume Overall, the results showed that the incorporation of nanosilica from RHA improved the oil well cement compressive strength and oil well cement porosity In conclusion, green nanosilica from RHA can be a potential candidate to replace the commercial nanosilica to enhance the oil well cement properties as well as to prevent the migration of undesirable fluid which can lead to major blowout

Introduction

Oil well cementing is the process to provide zonal isolation by mixed cement slurry with water and then pumped down into wellbore through casing to open holes or vital point in the annulus [1,2] The most common purposes of oil well cementing are; to prevent the movement of fluid between formations and to provide the support and strengthen the casing The cement properties such as porosity and compressive strength play an important role in the success of cementing operation [3] In order to improve the properties of cement, a few additives such as accelerators and inhibitors should

be added to the cement slurries After a few decades, cement additive limitations in micro and macro sized particles have been found [4,5] Therefore, many researchers have turned to nano sized particles especially nanosilica and carbon nano tubes (CNT) Nanomaterials have unique and special physical properties because of larger surface area due the smaller size of particles [6,7] Many researchers believe that, particles in smaller size can improve the properties of some materials such as cement slurries and drilling fluids [8,9] Generally, oil well cements contain four main phases: C3A, C4AF,

C3S and C3S along with alkali, gypsum, lime and sulpahate [10]

The rheology and gelation process of cement is controlled by C3A and C4AF, while the compressive strength of cement is controlled by C2S and C3S The Eq 1 and Eq 2 showed the reaction between C2S and C3S with water to form Calcium Hydroxide (CH) and C-S-H gel The C-S-H gel acts as a binder for cement give strength and strengthen the matrix of cement [11,12,13]

Advanced Materials Research Vol 974 (2014) pp 26-32

© (2014) Trans Tech Publications, Switzerland

doi:10.4028/www.scientific.net/AMR.974.26

Addition of nanomaterials on cement slurries will accelerate the formation of C-S-H gel and directly strengthen the cement In this research, we formulated the oil well cement slurries using nanosilica from RHA and studied the physical and structural properties of oil well cement improved with nanosilica from RHA

3CHH-S-C6H

S

CHH-S-C4H

S

Methodolody

Materials The cement powder used in this study was oil well cement Class G according to American

Petroleum Institute (API) standards [14,15] The Cement was purchased from Lafarge Malayan Cement Berhad Rice husk ash (RHA) obtained from Bernas Malaysia

Synthesis nanosilica from rice husk ash (RHA) RHA was washed thoroughly with water to

remove soil and dusts comply and then dried under the sun for 48 hours RHA was sieved using a sieve shaker and then grinded by using a ball mill grinder RHA was stirred with 2.5 N sodium hydroxide solutions and boiled in covered flask for 3 hours The solutions were filtered and residue was washed with boiling water The filtrate was added 5N H2SO4 until pH 2 and then added NH4OH until pH 8.5 and allowed to room temperature for 3.5 hours The filtrate was dried at 120 ˚C for 12 hours and its chemical functionalities were characterized using fourier transform infrared spectroscopy (FTIR) Pure nanosilica was extracted by refluxing with 6N HCl and dissolved in in 2.5

N NaOH by continuous stirring for 10 hours and then H2SO4 was added to adjust pH from 7.5 to 8.5 The precipitated nanosilica was washed and dried at 50 ˚C for 48 hours and silica content in RHA was examined by X-ray flouresece (XRF) and Field Emission Scanning Electron Microscopy (FESEM) was used to obtain the size of RHA particles [16]

Sample preparation.The sample of cement slurry was prepared according to API standard The specification gives the standard procedure for sample condition prior testing High speed propeller mixer was used to initial mixing process The cement powder and RHA was premixed and thereafter added to water and others additive in the mixer at the highly speed for 5 minutes In this study, the ratio of water/cement 0.5 was used [17]

Molding process The cement molding process was followed the API procedures The prepared

slurries was placed in the moulds sized (2 in x 2in x 2in) in a layer equal to half of mold depth and puddle for 25 times per specimen with pudding rod The prepared slurries were placed in all specimen compartments before commenced the pudding operation After pudding the layer, the remaining slurries was stirred using pudding rod and strike off the excess slurries on the mould top using a straightedge The dry cover plate was placed on the mould top before the sample ready for curing process

Curing process The prepared mould was cured in a curing bath The sample was cured at

atmospheric pressure and the temperature of 65.5 OC (150 OF) for 8 hours as per the API standard procedures and specifications

Porosity test In the porosity test, the hardened cement was dried at room temperature for 24 hours to

remove all the moisture content After that, the dried cement cube ware weighted and recorded The dry cement cube was submerged into tap water for 2 hours and then the wet cement cube was weighted The porosity of cement slurries was calculated using Eq 3 and Eq 4

waterofgravityspecific

cubecementdry

ofweightcube

cementwet

ofweightvolume

(3)

cementof

volumeBulk

volumePore

Compressive strenght test In the compressive strength test, cement slurry was prepared according

to API Standard under section 5 and immediately poured in the prepared molds in a layer equal to half

of mold depth and puddle for 25 times per specimen with pudding rod In order to eliminate the segregation, the remaining cement slurries were stirred and the molds are filled to overflowing and puddled as before After that, the prepared molds were placed in the water bath for curing process at high temperature and atmospheric pressure according to schedule 5G for 8 hours Then, the mold was crushed with 3000 kN pressure using compressive strength machine

Results and Discussion

Characterization of nanosilica from rice husk ash (RHA) The rice husk ash (RHA) sample was

extracted using sodium hydroxide which generated the yield of pure silica up to 60.3 % The concentration of sodium hydroxide had strongly affected dissolution of silica from raw rice husk ash and also removed some impurities which could not be dissolved from the main product Based on Fig

1, nanosilica from rice husk ash (RHA) were mainly composed of amorphous silica and these were showed by the band located around 750.55 – 835.67 cm-1 (Si-H group) and 1040.02-1050.7

cm-1(Si-O-Si stretching) The results showed that, synthesized and precipitation of RHA using sodium hydroxide concentration has no significant changes in the FTIR peak intensities as compared

Table 1: Particle size and specific surface area for raw RHA and synthesized nanosilica from RHA

(a) (b)Figure 2: Cross - sectional of FESEM images of (a) raw RHA with magnified 2000 times and (b)

sythesized nanosilica from RHA with magnified 12000 time

The effect of nanosilica from RHA on cement porosity In general, addition of fines particles

reduces the porosity of the cement slurries Fig 3 shows the reduction percentage for porosity of oil well cement after 8 hours curing time when incorporated with raw RHA, nanosilica from RHA and commercial nanosilica

Figure 3: Reduction percentage for porosity of oil well cement after 8 hours curing time

Addition of 0 wt %to 2 wt% commercial nanosilica to cement slurries reduced the cement porosity range from 21.82 % – 11.01 % pore volume Meanwhile, addition of nanosilica from RHA in the oil well cement reduced the cement porosity range from 21.81 % to 13.11 % pore volume However, addition of raw RHA only showed a slight reduction from 21 % to 18 % pore volume Addition of above 1 wt% raw RHA, commercial nanosilica and nanosilica from RHA to oil well cement slurries admixture does not change the porosity of oil well cement because the limitation of micro size of cement particles The fine size of additives such as nanosilica from RHA and commercial nanosilica that were placed into the cement pores leads to reduction of cement porosity [21,22] The nanosilica acts as a filter material to fill the interstitial space between cement particles and results in lower porosity [23,24] These results concluded that nanosilica from RHA able to offers the same performances as commercial nanosilica in reducing cement porosity

Effect of compressive strength on cement properties Fig 4 shows the compressive strength of oil

well cement after 8 hours curing time In general increased amount of additives, increased the compressive strength Based on the result, the compressive strength increased in the sequence of raw RHA < nanosilica from RHA < commercial nanosilica With addition of 1.5 wt % additive into cement slurries, commercial nanosilica showed highest compressive strength as compared to cement added with nanosiliza from RHA and raw RHA from 3022 psi to 3266 psi Meanwhile, the addition of nanosilica from RHA produced maximum compressive strength at 3208 psi The particle sizes for raw RHA, nanosilica from RHA and commercial silica are approximately 1000 – 5000 nm, 46.14 – 72.77

nm and 10 – 20 nm respectively This result concluded that, the oil well cement compressive strength increased as the additives particle sizes decreased This is because, increased in the particles size leads

to increase the surface area and finally increased the compressive strength [25,26]

Figure 4: The compressive strength (psi) of oil well cement after 8 hours curing time

In general, raw RHA and nanosilica from RHA produced less compressive strength than commercial nanosilica but still in API specification ranges, that is above the minimum of 1500 psi compression strength The reaction between calcium hydroxide and calcium oxide in oilwell cement with RHA produced more tricalcium silicate which hold the grain within the cement molecule structure, results in increament of the compressive strength [27,28] Besides that, fine particles of nanosilica from RHA reacted with excess calcium oxide and calcium hydroxide to produce an additional cementitious material of tricalcium silicate hydrates which will filled with existing pores within the cement and thus increased the oilwell cement compressive strength [29,30] Further addition up to 2 wt % of commercial nanosilica and nanosilica from RHA reduced the slurry density

which ultimately leads to reduction of the cement compressive strength

Conclusion

Cement properties play an important role to determine the successful of oil well completion operation This study concluded that addition of nanosilica affects the oil well cement properties which is porosity and compressive strength Synthesized nanosilica from RHA using precipitation method results in reduction of particle size and surface area Besides that, synthesized and precipitation of RHA using sodium hydroxide concentration has no significant changes in the FTIR peak intensities as compared to commercial nanosilica Nanosilica from RHA which were mainly composed of amorphous silica showed band located around 750.55 – 835.67 cm-1 (Si-H group) and 1040.02-1050.7 cm-1(Si-O-Si) stretching Addition of nanosilica from both commercial and synthesized from RHA show a sigificant effects on oil well cement porosity and compressive strength Addition of 0 wt % to 2 wt% commercial nanosilica and nanosilica from RHA into cement