Smithells Light Metals Handbook Episode 5 pot

76 Smithells Light Metals HandbookTable 4.4 MISCELLANEOUS ALUMINIUM ALLOYS Aerospace Composition % Single figures indicate maximum Other Properties of material Suitability for: Heat trea

(minimum)††

70 80°C

Boiling water Water at

70 80°C

Water at

70 80°C

Water or oil Oil at 80 90°C

LM13 and LM26 Excellent at elevated resistance alloy machinability temperatures

Grav die alloy

Mechanical properties sand cast SI (Imperial units in brackets)

Tensile stress min., MPa

(tonf in 2)

220(14.2) 220(14.2) 280(18.1) 324(21.0) 263(17.0)

Expected 0.2% proof stress,

min., MPa

210 240 165 200 200 240 310(20.1) 250(16.2)

Mechanical properties chill cast SI units (Imperial units in brackets)

Tensile stress min., MPa

(tonf in 2)

170 278(18.0) 280(18.1) 265(17.1) 310(20.1) 402(26.0) 340(22.0)

Expected 0.2% proof stress,

min., MPa

HB 100 150 HB 100 130

†[ ] signifies obsolete specification E Excellent F Fair G Good P Poor U Unsuitable

‡Si C Fe 1.0 max (Ge General purpose alloy; SP Special purpose alloy as per BS 1490: 1988)

§Or 5 days ageing at room temp

ŁŁCan substitute stabilizing treatment at 200 250°C if used for pistons

††Allow to cool to 480°C before quench.

76 Smithells Light Metals Handbook

Table 4.4 MISCELLANEOUS ALUMINIUM ALLOYS

Aerospace

Composition % (Single figures indicate maximum)

Other

Properties of material

Suitability for:

Heat treatment

or boiling water than 160°C

Mechanical properties Sand cast SI units (Imperial units in brackets)

Tensile stress min,

Expected 0.2% proof stress,

(11.0-12.3)

Mechanical properties chill cast SI units (Imperial units in brackets)

Tensile stress min,

Ł[ ] obsolete

†0.05% min if Ti alone used for grain refinement

††Not normally used in this form

§Or 8 h at 435 445 C then raise to 490 500 C for further 8 h and quench as in table

ŁŁDo not retain castings in oil for more than 1 h

ŁŁŁNot generally recommended since occasional brittleness can develop over long periods

Aluminium and magnesium casting alloys 77

Table 4.4 (continued )

Specification BS 1400: 1988 LM28TE(SP) LM28TF(SP) [LM23P]Ł [LM15WP]Ł

Aerospace

Composition % (Single figures indicate maximum)

Properties of material

Suitability for:

Heat treatment

Oil or air blast

(195 205) (at least 24 h after cast)

Special properties Piston alloy Aircraft engine High mechanical Good strength

elevated temps treatment See‡‡ Mechanical properties sand cast SI units (Imperial units in brackets)

Tensile stress min,

Expected 0.2% proof stress,

HB100 140

Mechanical properties chill cast SI units (Imperial units in brackets)

Tensile stress min,

Expected 0.2% proof stress

HB 90 130 (10.4 12.3)

HB 100 140

††Can be furnace cooled to 385 395°C before quench Do not retain in oil for more than 1 h Further quench in water or air

‡‡Alternative-room temp age-harden for 3 weeks

Note:

E Excellent F Fair G Good P Poor U Unsuitable

Table 4.5 HIGH STRENGTH CAST AL ALLOYS BASED ON AL-4.5 CU

Designation

Al Assoc (USA)

Cu 4.0 5.2 4.0 5.2 4.0 5.0 4.0 5.0 4.2 5.0 4.2 4.9 4.2 5.0 4.2 5.0 4.2 5.0 4.2 5.0

Mg 0.15 0.55 0.20 0.55 0.15 0.35 0.20 0.35 0.15 0.35 0.20 0.35 0.15 0.35 0.20 0.35 0.15 0.35 0.20 0.35

Mn 0.20 0.50 0.20 0.50 0.20 0.40 0.20 0.40 0.10 0.05 0.20 0.50 0.20 0.50 0.20 0.50 0.20 0.50

Ti 0.15 0.35 0.15 0.35 0.15 0.35 0.15 0.35 0.15 0.30 0.15 0.25 0.15 0.3 0.15 0.25 0.15 0.30 0.15 0.25

Aluminium and magnesium casting alloys 79

Table 4.6 MINIMUM REQUIREMENTS FOR SEPARATELY CAST TEST BARS

Alloy Sand/Die TreatmentŁ MPa MPa or 4 ð diam 500 kgf 10 mm

ŁFor temper designations see Table 7.3

Table 4.7 TYPICAL PROPERTIES OF SEPARATELY CAST TEST BARS

EI% Typical

Alloy Sand/Die TreatmentŁ MPa MPa or 4 ð diam 500 kgf 10 mm

ŁElevated temperature properties

Table 4.8 ZIRCONIUM-FREE MAGNESIUM ALLOYS

Grain refined (0.05 0.2 mm chill cast) when superheated to 850 900°C or suitably treated with carbon (as hexachlorethane)

Composition % (Single figures indicate maximum)

Material properties

Characteristics Sand and permanent‡ mould Special melting technique required

°

Solution:

Equivalent DTD

Composition % (Single figures indicate maximum)

Material properties

Characteristics Sand, permanent mould and die (pressure) Sand, permanent mould and die (pressure)

Weldability (Ar-Arc process) Good, but some difficulty with die Good, but some difficulty with die

continued overleaf

Table 4.8 (continued )

Heat treatment

Solution:

BSS L series

Equivalent DTD

Composition % (Single figures indicate maximum)

Cu C Si C Fe C Ni

Material properties

Founding Sand and permanent mould High pressure die Sand, permanent and high pressure die

°

Heat treatment continued

Precipitation:

Time, h

Temperature,°C

Stress relief:

Mechanical propefties sand cast (SI units first, Imperial units following in brackets)

Tensile strength (min), MPa (tonf in 2) 140 (9.1) 200 (13.0) 140 (9.1) 200 (13.0)

0.2% proof stress (min), MPa (tonf in 2) 85 (5.5) 80 (5.2) 85 (5.5) 80 (5.2)

Mechanical properties chill cast (SI units first, Imperial units following in brackets)

Tensile strength (min), MPa (tonf in 2) 185 (12.0) 230 (14.9) 185 (12.0) 230 (14.9)

0.2% proof stress (min), MPa (tonf in 2) 85 (5.5) 80 (5.2) 85 (5.5) 80 (5.2)

resistance High-purity alloy offers good corrosion resistance

continued overleaf

Table 4.8 (continued )

ASTM designation

Equivalent DTD

Precipitation:

Stress relief:

Mechanical properties sand cast (SI units first, Imperial units following in brackets)

Tensile strength (min), MPa (tonf in 2/†† 125 (8.1) 200 (13.0) 200 (13.0) 125 (8.1) 185 (12.0) 185 (12.0) 0.2% proof stress (min), MPa (tonf in 2) 95 (6.2) 85 (5.5) 130 (8.4) 85 (5.5) 80 (5.2) 110 (7.1)

Mechanical properties chill cast (SI units first, Imperial units following in brackets)

Tensile strength (min), MPa (tonf in 2) 170 (11.0) 215 (13.9) 215 (13.9) 170 (11.0) 215 (13.9) 215 (13.9) 0.2% proof stress (min), MPa (tonf in 2) 100 (6.5) 85 (5.5) 130 (8.4) 85 (5.5) 80 (5.2) 110 (7.1)

Increased proof stress after full heat treatment

BSS L series

Equivalent DTD

Precipitation:

Stress relief:

Time, h

Temperature,°C

Mechanical properties sand cast (SI units first, Imperial units following in brackets)

0.2% proof stress (min), MPa (tonf in 2) 130 pressure die-cast 125

Mechanical properties chill cast (SI units first, Imperial units following in brackets)

Max temp 120°C with superior elevated temperature

properties

TS Stress relieved only ADOutstanding; better than grey cast iron

TE Precipitation treated only BDEquivalent to cast-iron

TB Solution treated only CDInfersior to cast-iron but better Al-base cast alloys

TF Solution and precipitation treated ŁŁADParticularly recommended

†GP General purpose alloy BDSuitable but not especially recommended

SP Special purpose alloy CDNot recommended where strength at elev temps is likely to be an important consideration

‡Permanent mouldDgravity die casting ††1 MPaD1 H m 2D0 064 75 tonf in 2

§Ability to fill mould easily A, B, C, indicate decreasing castability ‡‡SO2or CO2atmosphere

Table 4.9 MAGNESIUM-ZIRCONIUM ALLOYS

Inherently fine grained (0.015 0.035 mm chill cast)

Equivalent DTD

Composition % (Single figures indicate maximum)

Silver

Thorium

Iron

Silicon

Manganese

Material properties

Founding characteristics Good in sand and permanent Good in sand and permanent Excellent in sand and permanent

Resistance to creep at elevated temperature Poor Moderate Good up to 250°C

Solution:

Time, h

Temperature,°C

Cooling

Precipitation:

Post weld stress relief:

treatment

Mechanical properties sand cost SI units (Imperial units in brackets)

Tensile strength min, MPa (tonf in 2) 230 (14.9) 200 (13.0) 140 (9.1)

Mechanical properties chill cast SI units (Imperial units in brackets)

Tensile strength min, MPa (tonf in 2) 245 (15.9) 215 (13.9) 155 (10.0)

Not suitable for spidery complex applications tightness at room and elevated

continued overleaf

Table 4.9 (continued )

BSS L series

Composition % (Single figures indicate maximum)

Silver

Material properties

Founding characteristics As per MAG7 but more sluggish Similar to MAG5 Good

Resistance to creep at elevated temperature Good up to 350°C Fair Poor

Precipitation:

Post weld stress relief:

Air cool

Mechanical properties sand cast SI units (Imperial units in brackets)

Tensile strength min, MPa (tonf in 2) 185 (12.0) 255 (16.5) 275 (17.8)

Mechanical properties chill cast SI units (Imperial units in brackets)

ductility and excellent fatigue resistance

Structural parts aircraft, etc

continued overleaf

Table 4.9 (continued )

BSS L series

Composition % (Single figures indicate maximum)

Rare earth metals 1.2 2.0‡ 2.0 3.0‡ 1.8 2.5‡ 0.1 1.5 3.0‡ 2.0 4.0¶¶¶ 2.4 4.4¶¶¶

(SP)

BSS L series

Material properties

Founding characteristics Good Good Good Less easy to

found

Tendency to hot tearing Little Little Little Very little Little Very little Very little

Tendency to micro-porosity Slight Slight Slight Negligible Slight Slight Slight

Weldability (Ar-Arc process) Very good Very good Very good Very good Very good Very good Very good

Strength at elevated

temperature††

Resistance to creep at elevated

temperature

Good up to

200°C

Good up to

200°C

Good up to

200°C

Good up to

350°C for short time applications

Good up to

200°C

Very good up to

250°C

Very good up to

250°C Corrosion resistance Moderate Moderate Moderate Moderate Moderate Excellent Excellent

Casting temperature range,°C 720 810 720 810 720 810 720 810 720 810 720 810 720 810

Heat treatment

Solution:

Cooling Water or oil Water or oil Water or oil Air cool Water or oil Air cool Water or oil Precipitation:

Air cool Air cool Air cool Air cool Air cool Air cool Air cool

Table 4.9 (continued )

BSS L series

Post-weld stress relief:

followed by above

followed by above

followed by above

followed by above

Mechanical properties sand cast SI units (Imperial units in brackets)

Tensile strength min, MPa

0.2% proof stress min, MPa

Mechanical properties chill cast SI units (Imperial units in brackets)

Tensile strength min, MPa

0.2% proof stress min, MPa

thick and thin section castings

Good elevated temperature (up

to 250°C) short time tensile and fatigue props

Similar to MSRA-B

Superior short time tensile and creep resistance

at temperatures around 300°C

Similar to MSR alloys but less but less

Excellent strength up to

300°C for short time

applications

Excellent corrosion resistance

Excellent strength

up to 250°C for long time applications Excellent corrosion resistance

ŁSee footnote to Table 4.1 ††See footnote to Table 4.1.

†See footnote to Table 4.1. ‡‡SO2or CO2atmosphere

‡Neodymium-rich rare rearths (others Ce-rich) ¶¶Castings to be loaded into furnace at operating temperature

¶See footnote to Table 4.1. ŁŁŁBut only before hydriding treatment

ŁŁSee footnote to Table 4.1. †††In hydrogen at atmospheric pressure

§See footnote to Table 4.1. ‡‡‡Thorium containing alloys are being replaced by alternative magnesium based alloys

¶¶¶Neodymium and heavy rare earths

5 Equilibrium diagrams

94 Smithells Light Metals Handbook

Ag Al