Bsi bs en 10083 3 2006

EN 10083-3:2006 E 4 1 Scope This part of EN 10083, in addition to Part 1, specifies the technical delivery requirements for: Clause 1, manufactured from the direct hardening alloy stee

Classification

All steel grades are classified according to EN 10020 as alloy special steels.

Designation

For the steel grades covered by this document, the steel names as given in the relevant tables are allocated in accordance with EN 10027-1

For the steel grades covered by this document, the steel numbers as given in the relevant tables are allocated in accordance with EN 10027-2

5 Information to be supplied by the purchaser

Mandatory information

Licensed Copy: Institute Of Technology Tallaght, Institute of Technology, Tue Aug 29 10:11:45 BST 2006, Uncontrolled Copy, (c) BSI

Options

This document outlines various options available to the purchaser, which include specific heat treatment conditions, surface conditions, product analysis verification, hardenability requirements, mechanical properties verification, fine grain size checks, non-metallic inclusion content verification, internal soundness requirements, surface quality standards, permissible decarburization depth, suitability for bright drawing, removal of surface defects, and inspection of surface condition and dimensions at the manufacturer's facility Additionally, it addresses any special marking requirements for the products If the purchaser does not express a desire to implement these options, the supplier will adhere to the basic specifications.

This article discusses 20 round bars with a nominal diameter of 20 mm and a length of 8000 mm, manufactured from steel grade 25CrMo4 (1.7218) in accordance with EN 10060 and EN 10083-3 These bars are in the heat treatment condition +A and come with an inspection certificate 3.1 as specified by EN 10204.

General

The manufacturing process of steel and of the products is left to the discretion of the manufacturer with the restrictions given by the requirements in 6.2 to 6.4

Deoxidation

All steels shall be killed.

Heat treatment and surface condition at delivery

Unless otherwise agreed at the time of enquiry and order, the products shall be delivered in the untreated, i.e hot worked, condition

NOTE Depending on the product shape and dimensions, not all steel grades can be delivered in the hot worked untreated condition (e.g steel grade 30CrNiMo8)

If so agreed at the time of enquiry and order, the products shall be delivered in one of the heat-treatment conditions given in Table 1, lines 3 to 6

If so agreed at the time of enquiry and order, the products shall be delivered with one of the particular surface conditions given in Table 2, lines 3 to 7.

Cast separation

The products shall be delivered separated by cast

Chemical composition, hardenability and mechanical properties

Table 1 shows the combinations of usual heat-treatment conditions at delivery, product forms and requirements as specified in Tables 3 to 8

Except where the steels are ordered in the quenched and tempered condition, the steels may be supplied with or without hardenability requirements (see Table 1, columns 8 and 9)

7.1.2.1 The chemical composition determined by cast analysis shall comply with the values in Table 3

7.1.2.2 Permissible deviations between the limiting values for cast analysis and the values for product analysis are given in Table 4

The product analysis shall be carried out when specified at the time of the order (see A.5)

Where the steel is ordered by using the symbols for normal (+H) or restricted (+HL, +HH) hardenability requirements, the hardenability values given in Table 5 or Table 6 shall apply

Where the steel is ordered without hardenability requirements, the requirements for mechanical properties specified in Table 8 for the quenched and tempered condition apply

In this case the hardenability values given in Table 5 are for guidance purposes only

The mechanical property values listed in Table 8 pertain to test specimens that have been quenched and tempered, prepared in accordance with EN 10083-1:2006, as illustrated in Figures 1, 2, and 3 (refer to footnote a in Table 1 for additional details).

For the hardness of surface hardened zones of steels intended for flame and induction hardening the specifications in Table 9 apply.

Machinability

All steels supplied in the soft annealed (+A) condition are suitable for machining For enhanced machinability, it is advisable to order grades with a designated sulphur range or those that have undergone specific treatments, such as calcium treatment, as detailed in Table 3, footnote c.

Shearability of semi-finished products and bars

Under optimal conditions, such as avoiding local stress peaks, pre-heating, and using blades with a profile tailored to the product, all steels can be sheared effectively in the soft-annealed (+A) state.

7.3.2 Steel grades without boron up to steel grade 42CrMoS4 and the boron-alloy steel grades 33MnCrB5-

The grades 2 and 39MnCrB6-2 are shearable under appropriate conditions when supplied in the "treated to improve shearability (+S)" state, meeting the hardness specifications outlined in Table 7, along with the hardenability requirements detailed in Tables 5 and 6.

7.3.3 Under suitable conditions steel grades 20MnB5, 30MnB5, 38MnB5 and 27MnCrB5-2 and the corresponding grades with requirements on hardenability (see Table 5) are shearable in the untreated condition.

Structure

7.4.1 All steels shall have a fine grain structure with an austenite grain size of 5 or finer, when tested in accordance with EN ISO 643 For verification see A.2

7.4.2 The steels shall have a degree of cleanness corresponding to the special steel quality (see A.3 and

Internal soundness

When placing an order, it is essential to establish the internal soundness requirements of products, ideally referencing European standards Specifically, EN 10160 outlines the ultrasonic testing criteria for flat products with a thickness of 6 mm or more, while EN 10308 details the ultrasonic testing requirements for steel bars.

Surface quality

7.6.1 All products shall have a smooth finish appropriate to the manufacturing processes applied, see also 6.3.3

Minor surface imperfections, such as scores from rolled-in scale in hot-rolled products, that may arise under standard manufacturing conditions should not be considered defects.

7.6.3 Where appropriate, requirements relating to the surface quality of the products shall be agreed upon at the time of enquiry and order, if possible with reference to European Standards

Sheet/plate and wide flats are delivered with surface class A, subclass 1 according to EN 10163-2 unless otherwise agreed at the time of enquiry and order

Bars and rods are delivered with surface class A according to EN 10221 unless otherwise agreed at the time of enquiry and order

7.6.4 Requirements relating to the permissible depth of decarburization may be agreed at the time of enquiry and order

The depth of decarburization shall be determined in accordance with the micrographic method specified in

7.6.5 If suitability of bars and rods for bright drawing is required, this shall be agreed at the time of enquiry and order

7.6.6 The removal of surface defects by welding shall only be permitted with the approval of the customer or his representative

If surface discontinuities are repaired, the method and maximum depth of removal shall be agreed at the time of enquiry and order.

Dimensions, tolerances on dimensions and shape

The nominal dimensions and tolerances for the product must be established during the inquiry and ordering process, ideally referencing the relevant dimensional standards, such as EN 10083-1:2006, Annex D.

Testing procedures and types of documents

Products that adhere to this document must be ordered and delivered with an inspection document as outlined in EN 10204 The specific type of document should be determined during the inquiry and ordering process In the absence of a specified document type in the order, a test report will be provided.

8.1.2 For the information to be included in a test report, see EN 10083-1:2006, 8.1.2

8.1.3 For the information to be included in an inspection certificate, see EN 10083-1:2006 8.1.3

8.1.4 Unless otherwise agreed at the time of the order, inspection of surface quality and dimensions shall be carried out by the manufacturer.

Frequency of testing

Sampling shall be in accordance with Table 10

The test units and the extent of testing shall be in accordance with Table 10

Tests to be carried out for specific inspection

8.3.1 Verification of hardenability, hardness and mechanical properties

For steels ordered without hardenability requirements (lacking the symbols +H, +HH, or +HL), the hardness and mechanical properties specified for the relevant heat-treatment condition must be verified, except for the requirement in Table 1, Footnote a, which pertains to the mechanical properties of reference test pieces This requirement is only applicable if supplementary requirement A.1 is specified in the order.

For steels being ordered with the symbol +H, +HH or +HL in the designation (see Tables 5 and 6), unless otherwise agreed, only hardenability requirements according to Table 5 or 6 shall be verified

A sufficient number of products shall be inspected to ensure compliance with the specification

9 Preparation of samples and test pieces

Selection and preparation of samples for chemical analysis

The preparation of samples for product analysis shall be in accordance with EN ISO 14284.

Location and orientation of samples and test pieces for mechanical tests

Preparation of samples shall be in accordance with Table 10 and EN 10083-1:2006, 9.2.1

Preparation of test pieces shall be in accordance with Table 10 and EN 10083-1:2006, 9.2.2.

Location and preparation of samples for hardness and hardenability tests

Identification of samples and test pieces

Samples and test pieces shall be marked so that the original products and their location and orientation in the product is known

Chemical analysis

Mechanical tests

Hardness and hardenability tests

10.3.1 Hardness in treatment conditions +A and +S

For products in treatment conditions +A (soft annealed) and +S (treated to improve shearability), the hardness shall be measured in accordance with EN ISO 6506-1

Manufacturers have the option to verify hardenability through calculations, with the method of calculation being at their discretion Upon agreement during the inquiry and order process, manufacturers are required to provide sufficient information about the calculation, enabling customers to confirm the results.

In the absence of a calculation formula or in the event of a dispute, an end quench hardenability test must be conducted following EN ISO 642 standards The quenching temperature should adhere to the specifications outlined in table 11, and the hardness values must be measured according to EN ISO 6508-1 using scale C.

The surface hardness of steels after flame or induction hardening (see Table 9) shall be determined in accordance with EN ISO 6508-1, scale C.

Retests

The manufacturer must appropriately label products, bundles, or boxes to clearly indicate the cast, steel grade, and delivery origin.

Table 1 outlines the combinations of typical heat treatment conditions at delivery, along with product forms and requirements specified in Tables 3 to 8 The notation "x" indicates applicable requirements for steel ordered under the designations provided in Table 3, Table 5, or Table 6.

1 Heat treatment condition at delivery Symbol Semi- finished products Bars Rod Flat products Hammer and drop forgings8.1 8.2 9.1 9.2 9.3 2 Untreated none or +Ux x x x x a 3 Treated to improve shearability

+S xx - x - Table 7 column +Sa 4 Soft annealed +Ax x x xb x Maximum hardness Table 7 column +Aa

Hardenability values according to Table 5 or 6 5 Quenched and tempered+QT- x x xb x

Chemical composition according to Tables 3 and 4 Mechanical properties according to

Certain treatment conditions, such as specific annealing processes to achieve desired structures, can be agreed upon during the inquiry and ordering stages The annealing treatment for spheroidal carbide, necessary for cold upsetting and cold extrusion, is addressed by EN 10263-4 For deliveries in untreated condition, as well as in "treated to improve shearability" and "soft annealed" conditions, the mechanical properties outlined in Table 8 can be achieved for the ruling end cross-section after appropriate heat treatment However, it is important to note that not all dimensions of flat products can be delivered in this heat treatment condition.

Table 2 — Surface condition at delivery

1 Surface condition at delivery Symbol x indicates in general applicable for Notes

Semi- finished products (such as blooms, billets)

Hammer and drop forgings (see note 2 in EN 10083- 1:2006, Clause 1)

5 Hot worked and blast cleaned

6 Hot worked and rough machined

Particular conditions supplied by agreement

Others - - - - - - - a In addition, it may be agreed that the products be oiled or, where appropriate, limed or phosphated

Table 3 presents various steel grades along with their chemical compositions, detailing the percentage by mass of elements such as carbon (C), silicon (Si), manganese (Mn), phosphorus (P), chromium (Cr), molybdenum (Mo), nickel (Ni), vanadium (V), and boron (B) The table categorizes steels into those without boron and those with boron, specifying the ranges for each element in different steel grades It emphasizes that elements not listed should not be intentionally added without the purchaser's agreement, except for finishing heat and boron to enhance hardenability Additionally, it notes that slight deviations from specified limits for cast analysis are permissible for certain elements, while improved machinability can be achieved through higher sulfur content upon request.

Table 4 — Permissible deviations between the product analysis and the limiting values given in Table 3 for the cast analysis

Element Permissible maximum content in the cast analysis

The permissible limit for B is set at \$B \leq 0.0050 \pm 0.0003\$, indicating that in a single cast, the deviation can occur either above the upper limit or below the lower limit specified in Table 3, but not simultaneously For steels with a sulphur content ranging from 0.020% to 0.040% as per cast analysis, the allowable deviation is \$\pm 0.005\%\$.

Table 5 presents the limiting values for the "C" scale Rockwell hardness of special steel grades with normal hardenability requirements, including H grades The table details various steel designations, their corresponding distances in millimeters from the quenched end, and the hardness values in HRC For instance, the steel grade 38Cr21.7003 has a maximum hardness range from 59 HRC at 1.5 mm to 27 HRC at 50 mm, with a minimum hardness of 51 HRC at 1.5 mm to 20 HRC at 50 mm Similarly, the 46Cr21.7006 grade shows a maximum hardness of 63 HRC at 1.5 mm, decreasing to 32 HRC at 50 mm, with a minimum hardness of 54 HRC at 1.5 mm to 20 HRC at 50 mm Other grades, such as 34Cr41.7033 and 41Cr41.7035, also exhibit specific hardness ranges, emphasizing the importance of these values in determining the suitability of steel for various applications.

T ab le 5 – (c ont inu ed) Steel designation Distance in mm from quenched end Hardness in HRC Name Number

The article presents a detailed overview of the limits of range for various steel grades, both with and without boron For steels without boron, the 30NiCrMo16-6 (1.6747) exhibits a maximum hardness ranging from 55 to 53 across different limits, while the minimum hardness varies from 47 to 45 In contrast, the 51CrV4 (1.8159) shows a maximum hardness between 65 and 59, with minimum values decreasing from 57 to 32 For boron-containing steels, the 20MnB5 (1.5530) has a maximum hardness of 50, decreasing to 33, and a minimum hardness ranging from 42 to 30 The 30MnB5 (1.5531) displays a maximum hardness of 56, with minimum values from 47 to 22 The 38MnB5 (1.5532) shows a maximum hardness of 60, while the minimum hardness ranges from 52 to 20 Other boron steels, such as 27MnCrB5-2 (1.7182) and 33MnCrB5-2 (1.7185), have maximum hardness values of 55 and 57, respectively, with minimum hardness values decreasing from 47 to 20 Lastly, the 39MnCrB6-2 (1.7189) maintains a maximum hardness of 59, with minimum values ranging from 51 to 32.

Table 6 presents the limiting values for the Rockwell hardness scale of special steel grades with restricted hardenability scatter bands, specifically the +HH and +HL grades The table includes various steel designations, such as 38Cr21.7003, 46Cr21.7006, and 34Cr41.7033, along with their corresponding hardness values measured in HRC at different distances from the quenched end For instance, the +HH maximum hardness for 38Cr21.7003 reaches up to 59 HRC, while the minimum is 54 HRC Similarly, 46Cr21.7006 shows a maximum of 63 HRC and a minimum of 57 HRC for the +HH grade The data highlights the hardness range for each steel grade, providing essential information for applications requiring specific hardness characteristics.

T ab le 6 – (c ont inu ed) Steel designation Distance in mm from quenched end HRC Hardness Name Number

The table presents the symbol limits of various steel grades, including 50CrMo4 (1.7228), CrNiMo6 (1.6582), 30CrNiMo8 (1.6580), 35NiCr6 (1.5815), 36NiCrMo16 (1.6773), 39NiCrMo3 (1.6510), 30NiCrMo16-6 (1.6747), and 51CrV4 (1.8159) Each grade is characterized by maximum and minimum hardness values under different conditions, denoted as +HH and +HL For instance, 50CrMo4 exhibits a maximum hardness of 65 and a minimum of 60, while CrNiMo6 shows a maximum of 58 and a minimum of 53 The data highlights the varying hardness limits across different steel grades, essential for applications requiring specific mechanical properties.

Table 7 — Maximum hardness for products to be supplied in the "treated to improve shearability (+S)" or "soft annealed (+A)" condition

Steel designation a Max HBW in condition b

34Cr4, 34CrS4 1.7033, 1.7037 255 223 37Cr4, 37CrS4 1.7034, 1.7038 255 235 41Cr4, 41CrS4 1.7035, 1.7039 255 c 241 25CrMo4, 25CrMoS4 1.7218, 1.7213 255 212 34CrMo4, 34CrMoS4 1.7220, 1.7226 255 c 223 42CrMo4, 42CrMoS4 1.7225, 1.7227 255 c 241

The 39MnCrB6-2 (1.7189) steel exhibits specific properties relevant to hardenability, applicable to various grades as outlined in Tables 5 and 6 However, these values do not apply to continuously cast slabs that have not undergone further deformation The need for soft annealing may arise based on the chemical composition and dimensions, especially for +HH-grades For applications where shearability is critical, it is recommended to order this steel in a "soft-annealed" condition, although it remains shearable in its untreated state Notably, the +A condition is not suitable for boron steels.

Table 8 presents the mechanical properties at room temperature for quenched and tempered steel, as specified in EN 10083-1:2006, Annex A The properties are categorized based on the diameter (d) for round products and thickness (t) for flat products For steel with a diameter of up to 16 mm or a thickness of up to 8 mm, specific minimum values for yield strength (R_e), tensile strength (R_m), elongation (A_min), reduction of area (Z_min), and impact toughness (KV_b) are provided As the diameter increases to ranges of 16 mm to 40 mm, 40 mm to 100 mm, and up to 250 mm, along with corresponding thickness ranges, the mechanical properties are adjusted accordingly to ensure optimal performance in various applications.

The article presents a detailed overview of various steel grades, including their specifications and mechanical properties For instance, the 38Cr21.7003 grade exhibits a tensile strength range of 550 to 950 MPa, with yield strengths of 14% to 17% Similarly, the 46Cr21.7006 grade shows a tensile strength of 650 MPa and yield strengths between 12% and 15% The 34Cr4 and 34CrS4 grades have tensile strengths of 700 MPa, with yield strengths ranging from 12% to 15% The 41Cr4 and 41CrS4 grades offer tensile strengths of 800 MPa, with yield strengths from 11% to 14% The 25CrMo4 and 25CrMoS4 grades have tensile strengths of 700 MPa, with yield strengths varying from 12% to 16% The 34CrMo4 and 34CrMoS4 grades provide tensile strengths of 800 MPa, with yield strengths between 11% and 15% The 42CrMo4 and 42CrMoS4 grades feature tensile strengths of 900 MPa, with yield strengths from 10% to 14% Lastly, the 34CrNiMo6 and 30CrNiMo8 grades have tensile strengths of 1000 MPa and 1050 MPa, respectively, with yield strengths ranging from 9% to 55%.

11 50 45 700 900 to 1100 12 50 45 35NiCr6 1.5815 740 880 to 1080 12 40 - 740 880 to 1080 14 40 35 640 780 to 980 15 40 35 - - - 36NiCrMo161.6773 1050 1250 to 1450 9 40 - 1050 1250 to 1450 9 40 30 900 1100 to 1300 10 45 35 800 1000 to 1200

11 50 45 39NiCrMo3 1.6510 785 980 to 1180 11 40 - 735 930 to 1130 11 40 35 685 880 to 1080 12 45 40 635 830 to 980 12 50 40 540 740 to 880 13 50 40 30NiCrMo16-61.6747 880 1080 to 1230 10 45 - 880 1080 to 1230 10 45 35 880 1080 to 1230 10 45 35 790 900 to 1050 11 50 35 880 900 to 1050 11 50 35 51CrV4 1.8159 900 1100 to 1300 9 40 - 800 1000 to 1200 10 45 30700 900 to 1100 12 50 30650 850 to 1000 13 50 30600 800 to 950 13 50 30 20MnB5 1.5530 700 900 to 1050 14 55 - 600 750 to 900 15 55 60 - - - 30MnB5 1.5531 800 950 to 1150 13 50 - 650 800 to 950 13 50 60 - - -

Table 8 presents the mechanical properties for the ruling section as specified in EN 10083-1:2006, Annex A It details the properties of steel based on diameter (d) for round products and thickness (t) for flat products, categorized into various ranges: for diameters up to 16 mm and thicknesses up to 8 mm; diameters between 16 mm and 40 mm with thicknesses between 8 mm and 20 mm; diameters from 40 mm to 100 mm with thicknesses from 20 mm to 60 mm; diameters from 100 mm to 160 mm with thicknesses from 60 mm to 100 mm; and finally, diameters from 160 mm to 250 mm with thicknesses from 100 mm to 160 mm Each category includes minimum values for yield strength (R_e), tensile strength (R_m), elongation (A_min), reduction of area (Z_min), and impact toughness (KV_b).

The article provides detailed specifications for various steel grades, including 38MnB5, 27MnCrB5-2, 33MnCrB5-2, and 39MnCrB6-2, highlighting their chemical compositions, mechanical properties, and processing temperatures Key parameters such as upper yield strength, tensile strength, percentage elongation after fracture, and impact strength are outlined, with specific values and ranges for each grade The document emphasizes the importance of meeting minimum impact strength requirements as per the specified standards, ensuring that no individual test value falls below 70% of the minimum Additionally, it references sampling methods in accordance with EN 10083-1:2006 for accurate assessment.

Table 9 — Surface hardness of steels after flame or induction hardening

The hardness values for 50CrMo4 (1.7228) at 58 HRC are applicable after quenching, tempering, and surface hardening, as specified in Table 11, followed by stress relieving at temperatures between 150°C and 180°C for approximately 1 hour These values pertain to cross-sections up to 100 mm in diameter for steels 46Cr2, 37Cr4/37CrS4, and 41Cr4/41CrS4, and up to 250 mm in diameter for steels 42CrMo4/42CrMoS4 and 50CrMo4 It is important to consider that surface decarburization may result in reduced hardness in the surface-hardened areas.

Tiêu đề	Steels for quenching and tempering — Part 3: Technical delivery conditions for alloy steels
Trường học	Institute of Technology Tallaght
Chuyên ngành	Engineering
Thể loại	Standard
Năm xuất bản	2006
Thành phố	Tallaght

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