LM5

Aluminium Casting Alloy LM5

This aluminium alloy conforms to BS 1490:1988 LM5

Chemical Composition

	%		%		%
Copper	0.1 max	Magnesium	3.0-6.0	Silicon	0.3 max
Iron	0.6 max	Manganese	0.3-0.7	Nickel	0.1 max
Zinc	0.1 max	Lead	0.5 max	Tin	0.05 max
Titanium	0.2 max	Aluminium	Remainder	Others each	0.5 max
Others total	0.15 max

Mechanical Properties of aluminium casting alloy LM5

	Sand Casting	Gravity Die Cast
0.2% Proof Stress (N/mm²)	90-110	90-120
Tensile Strength (N/mm²)	140-170	170-280
Elongation (%)	3	5
Impact resistance Izod (Nm)	7.9	12.6
Brinell Hardness	50-70	60-70
Modulus of Elasticity (x10³ N/mm²)	71	71
Shear Strength (N/mm²)	140	-

Strength at elevated temperatures

Room temperature properties are largely maintained up to 200°C, but fall rapidly above 300°C.

Physical Properties of aluminium casting alloy LM5


Coefficient of Thermal Expansion (per °C @ 20-100°C)	0.000023
Thermal conductivity (cal/cm²/cm/°C @ 25°C)	0.33
Electrical conductivity (% copper standard @ 20°C)	31.0
Density (g/cm³)	2.65
Freezing range (°C) approx.	12

Strength at elevated temperatures

Room temperature properties are largely maintained up to 200°C, but fall rapidly above 300°C.

Physical Properties


Coefficient of Thermal Expansion (per C @ 20-100C)	0.000023
Thermal counducivity (cal/cm2/cm/C @ 25C)	0.33
Electrical conductivity (% copper standard @ 20C)	31.0
Density (g/cm3)	2.65
Freezing range (C) approx.	642-580

MACHINABILITY

LM5 machines very well and takes an excellent polish.

CORROSION RESISTANCE

LM5 is highly resistant to corrosion under most conditions and is superior to all other aluminium alloys for marine use.

ANODISING

LM5 may be anodised by any of the more common processes. A transparent colourless-to-whitish film is obtained according to the process used, and is suitable for decorative finishing.

APPLICATION AND GENERAL NOTES

LM5 is used where very high resistance to corrosion from sea water or marine atmospheres is required, for equipment used for the manufacture of foodstuffs, cooking utensils and chemical plant, and for an aluminium casting which needs to exhibit and maintain a surface of high polish.

Applications include, for example, door furniture, car fittings and trim, and similar aluminium castings where a colourless anodic film is required.

LM5 is mainly used for sand casting and, to a lesser extent, for gravity die casting, but high pressure aluminium die castings of relatively simple shapes has been made. LM5 is not heat-treated.

HOW can MRT Castings help you?