LM25 – Aluminium Casting Alloy
General Information
LM25 is a common generally purpose alloy of aluminium which is used where good mechanical properties are needed. It has a good resistance to corrosion and has high strength. It responds well to heat treatment and is available in four different conditions. Its uses are increased by its availability in as-cast and partially heat-treated condition as well.
LM25 Typical Applications
Common applications of LM25 are electrical, food, chemical, marine for example plus numerous other wide ranging uses. Its is extensively used in the automotive sector where cylinder blocks, wheels, heads and other parts are regularly cast in this aluminium alloy. LM25 offers a good machinability which is one of its major benefits.


LM25 Chemical Composition (%)
Copper 0.2 max
Zinc 0.1 max
Magnesium 0.20-0.60
Lead 0.1 max
Silicon 6.5-7.5
Tin 0.05 max
Iron 0.5 max
Titanium 0.2 max
Manganese 0.3 max
Nickel 0.1 max
Aluminium Remainder
Others: each 0.05 max
Others: total 0.15 max
LM25 – M – Mechanical Properties
0.2% Proof Stress (N/mm2) 80-100
Tensile Strength (N/mm2) 130-150
Elongation (%) 2
Impact Resistance Izod (Nm) –
Brinell Hardness 55-65
Endurance Limit (N/mm2) 70-100
Modulus Of Elasticity (x103 N/mm2) 71
Shear Strength (N/mm2) –