Smithells Light Metals Handbook Episode 3 ppt

Mechanical properties of light metals and alloys 39Table 3.6 continued T4 D Solution treated and naturally aged, will respond to precipitation treatment.. 3.2 Mechanical properties of m

Mechanical properties of light metals and alloys 35

Table 3.4 (continued )

36 Smithells Light Metals Handbook

Table 3.4 (continued )

H111 D Annealed H18 D Fully hard temper T4 D Solution treated and naturally aged T6 D Solution treated and precipitation treated

Table 3.5 ALUMINIUM ALLOYS CREEP DATA

(5052)

Mechanical properties of light metals and alloys 37

Table 3.5 (continued )

38 Smithells Light Metals Handbook

Table 3.5 (continued )

H111 D Annealed

T4 D Solution treated and naturally aged, will respond to precipitation treatment

T6 D Solution treated and artificially aged

Table 3.6 ALUMINIUM ALLOYS FATIGUE STRENGTH AT VARIOUS TEMPERATURES

C20 133

C20 173

Mechanical properties of light metals and alloys 39

Table 3.6 (continued )

T4 D Solution treated and naturally aged, will respond to precipitation treatment

T6 D Solution treated and artificially aged

3.2 Mechanical properties of magnesium and magnesium alloys

Table 3.7 MAGNESIUM AND MAGNESIUM ALLOYS (WROUGHT) TYPICAL MECHANICAL PROPERTIES AT ROOM TEMPERATURE

Specifications Tension Compression

Material % Form BS (Air) BS (Gen Eng.) ASTM Elektron MPa MPa % MPa 30 kg

Zn 0.5

Mn 0.3

(1 in diam.)

Zn 5.5 Bars and sections

Mn 0.8

5111

Zr 0.6

(Creep resistant) Mn 0.75

Mn 1.2

Nuclear alloys: Two wrought magnesium alloys (Magnox AL80; Mg0.75Al-0.005 Be and MN70; Mg0.75 Mn) of interest only for their nuclear and high-temperature properties have room-temperature tensile properties similar to those of AM503

ŁIt is usual to add 0.2 0.4% Mn to alloys containing aluminium to improve corrosion resistance M D As manufactured O D Fully annealed TE D Precipitation treated

ŁŁThorium-containing alloys are being replaced by alternative Mg alloys

Table 3.8 MAGNESIUM AND MAGNESIUM ALLOYS (CAST) TYPICAL MECHANICAL PROPERTIES AT ROOM TEMPERATURE

Specifications Tension Compression

composition or stress 0.2% UTS % stress 0.2% hardnesst Material % Condition BS (Air) BS (Gen Eng.) ASTM Elektron MPa MPa MPa VPN 30 kg

Zr 0.7

RE 1.2

Zr 0.7

RE 2.5

Zr 0.7

(Creep resistant) Zn 2.2

(Creep resistant Zn 2.2

Th 1.8

Zr 0.7

Zr 0.6

RE 2.0‡

Zr 0.6

Zr 0.6

Cu 0.07

RE 1.0‡

Th 1.0

Zr 0.7 RE()3.4

Zr 0.6

RE()3.0

Zr 0.6

Cu 2.7

Mn 0.5

ŁIt is usual to add 0.2 0.4% Mn to alloys containing aluminium to improve corrosion resistance RE D Cerium mischmetal containing approx 50% cerium RE./ D Neodymium plus Heavy Rare Earth metals

‡Fractionated rare earth metals: MSR-A contains 1.7%; MSR-B contains 2.5%

§Solution heat treated in an atmosphere of hydrogen

AC D Sand cast TE D Precipitation heat treated

TB D Solution heat treated TF D Fully heat treated

ŁŁThorium-containing alloys are being replaced by alternative Mg alloys

44 Smithells Light Metals Handbook

Table 3.9 MAGNESIUM AND MAGNESIUM ALLOYS (excluding high temperature alloys for which see table 3.10) TYPICAL TENSILE PROPERTIES AT ELEVATED TEMPERATURES

‘Short-time’ tension†

Mechanical properties of light metals and alloys 45

Table 3.9 (continued )

‘Short-time’ tension†

ŁIt is usual to add 0.2 0.4% Mn to alloys containing aluminium to improve corrosion resistance

†In accordance with BS1094: 1943; 1 h at temperature and strain rate 0.1 0.25 in in 1min1

‡Tested according to BS4A4 RE D Cerium mischmetal containing approx 50% Ce RE(D) D Neodymium enriched mischmetal RE./ D Neodymium plus Heavy Rare Earth metals

ŁŁThorium-containing alloys are being replaced by alternative Mg alloys

46 Smithells Light Metals Handbook

Table 3.10 HIGH TEMPERATURE MAGNESIUM ALLOYS TENSILE PROPERTIES AT ELEVATED TEMPERATURE

‘Short-time’ tension†

Cu 0.07 treated (EQ21)

Mg Ag RE(D) Ag 2.5 Sand cast High strength cast alloys with good elevated temperature













































properties for which see Table 3.9

(QH21)

RE()3.4 and fully

RE()3.0 and fully

ŁIt is usual to add 0.2 0.4% Mn to alloys containing aluminium to improve corrosion resistance

†In accordance with BS 1094: 1943; 1 h at temperature; strain rate 0.1 0.25 in in 1min 1

RE D Cerium mischmetal containing approx 50% Ce RE(D) D neodymium-enriched mischmetal

RE./ D Neodymium plus Heavy Rare Earths

Mechanical properties of light metals and alloys 47

Table 3.11 HIGH-TEMPERATURE MAGNESIUM ALLOYS LONG-TERM CREEP RESISTANCE

Stress to produce specified creep strains% Nominal

(ZRE1)

(RZ5)

Mg Th Zn ZrŁŁ Th 0.8 Sheet 250 100 Stress of 46 MPa (3 tonf in 2)

(ZT1)

(TZ6)

48 Smithells Light Metals Handbook

Table 3.11 (continued )

Stress to produce specified creep strains% Nominal

Cu 0.07 treated (EQ21)

(QH21)

ŁTotal strains

†4 6 h heating to test temperature followed by 16 h soaking at test temperature

RE D Cerium mischmetal containing approx 50% Ce

RE(D) D Neodymium-enriched mischmetal

RE./ D Neodymium plus Heavy Rare Earth metals

ŁŁThorium-containing alloys are being replaced by alternative Mg alloys

Mechanical properties of light metals and alloys 49

Table 3.12 HIGH-TEMPERATURE MAGNESIUM ALLOYS SHORT-TERM CREEP RESISTANCE

Stress to produce specified creep strains%

(ZRE1)

(RZ5)

(MTZ) treated

(ZTY)

(ZT1)

(TZ6)

†1 h heating to test temperature followed by 1 h soaking at test temperature

RE D cerium mischmetal containing approx 50% Ce

Table 3.13 MAGNESIUM AND MAGNESIUM ALLOYS FATIGUE AND IMPACT STRENGTHS

Fatigue strength† at specified cycles Impact strength§ for single blow fracture NominalŁ 105 5 ð 105 106 5 ð 106 107 5 ð 107 Test Unnotched Notched

Material % Condition State °C MPa MPa Mpa MPa MPa MPa °C J J

(AZM)

treated

(ZW3)

(Z5Z)

(ZE63)

(QH21)

(TZ6)

continued overleaf

Table 3.13 (continued )

Fatigue strength† at specified cycles Impact strength§ for single blow fracture NominalŁ 105 5 ð 105 106 5 ð 106 107 5 ð 107 Test Unnotched Notched

Material % Condition State °C MPa MPa Mpa MPa MPa MPa °C J J

ŁIt is usual to add 0.2 0.4% Mn to alloys containing aluminium to improve corrosion resistance § Hounsfield balanced impact test, notched bar values are equivalent to Izod values

ŁŁSolution heat treated in an atmosphere of hydrogen RE(D) D Neodymium enriched mischmetal

† Wohler rotating beam tests at 2960 c.p.m ŁŁŁThorium-containing alloys are being replaced by alternative Mg alloys

Mechanical properties of light metals and alloys 53

Table 3.14 HEAT TREATMENT OF MAGNESIUM ALLOY CASTINGS

Heat treatment conditions for magnesium sand castings can be varied depending on the particular components and specific properties required The following are examples of the conditions used for each alloy which will give properties meeting current national and international specifications

NominalŁ

Air cool

54 Smithells Light Metals Handbook

Table 3.14 (continued )

NominalŁ

Note:- Above 350°C, furnace atmospheres must be inhibited to prevent oxidation of magnesium alloys This can be achieved either by:

(i) adding 1/2 1%SO1gas to the furnace atmosphere; or

(ii) carrying out the heat treatment in an atmosphere of 100% dry CO2

ŁIt is usual to add 0.2 0.4% Mn to alloys containing aluminium to improve corrosion resistance

RE D Cerium mischmetal containing approximately 50% cerium TB D Solution heat treated

RE(D) D Neodymium-enriched mischmetal TE D Precipitation heat treated

RE./ D Neodymium plus Heavy Rare Earth metals TF D Fully heat treated

†Thorium-containing alloys are being replaced by alternative Mg alloys

Mechanical properties at subnormal temperatures

At temperatures down to 200°C tensile properties have approximately linear temperature coeffi-cients: proof stress and UTS increase by 0.1 0.2% of the RT value per°C fall in temperature, and elongation falls at the same rate: modulus of elasticity rises approximately 19 MPa (2800 lbf in 2) per°C over the range 0°to 100°C No brittle-ductile transitions have been found.

Tests at 70°C have suggested that the magnesium-zinc-zirconium alloys show the best retention

of ductility and notched impact resistance at this temperature.