LM4 is a British Standard (BS1490) aluminium casting alloy (Al-Si5Cu3), widely used in sand and die casting for engineering applications due to its versatility, machinability, and strength after heat treatment.
LM4 alloy primarily consists of aluminium as the base, with silicon and copper as major alloying elements, and limits on impurities like iron and zinc.
The standard composition per BS1490:1988 is detailed below:
| Element | Composition (%) |
|---|---|
| Silicon (Si) | 4.0 - 6.0 |
| Iron (Fe) | 0.8 max |
| Copper (Cu) | 2.0 - 4.0 |
| Manganese (Mn) | 0.2 - 0.6 |
| Magnesium (Mg) | 0.2 max |
| Zinc (Zn) | 0.5 max |
| Lead (Pb) | 0.1 max |
| Tin (Sn) | 0.1 max |
| Nickel (Ni) | 0.3 max |
| Titanium (Ti) | 0.2 max |
| Others (each/total) | 0.05 / 0.15 |
| Aluminium (Al) | Remainder |
This composition ensures good castability for thick and thin sections, pressure tightness, and enhanced properties post-heat treatment.






Price:
Price 185 INR / Kilograms
Minimum Order Quantity : 100 Kilograms
Surface Treatment : Other, Polished
Technique : Die Casting
Weight : approximately 78 kg per ingot
Alloy : Yes
Price 200 INR / Kilograms
Minimum Order Quantity : 100 Kilograms
Surface Treatment : Other, Unpolished / As Cast
Technique : Die Cast / Ingot Cast
Weight : 5 to 7 kg per ingot
Alloy : Yes
Price 200 INR / Kilograms
Minimum Order Quantity : 100 Kilograms
Surface Treatment : Other, Corrosion Proof
Technique : Die Casting
Weight : 810 kg per ingot
Alloy : Yes
Price 225 INR / Kilograms
Minimum Order Quantity : 100 Kilograms
Surface Treatment : Other, Unpolished / As Cast
Technique : Die Casting
Weight : 57 kg (each ingot)
Alloy : Yes