Development of an Aluminium Alloy for Cast Automotive Cylinder Heads

In-service conditions in aluminium automotive cylinder heads and, particularly the wear mechanisms which pertain during their operation, were studied and an alloy designed to best withstand these conditions.

The alloy is basically a hypereutectic Aℓ-Si-Ni-Cu alloy but solidified in such a way as to obtain a fully eutectic microstructure. Other elements are also included in the composition in order to dispersion harden the alpha-aluminium phase. The alloy can be used in the as-cast or heat-treated condition and is shown to have excellent wear and strength properties, at ambient and elevated temperatures.

It also has other enhanced properties, including castability, machinability and corrosion resistance, which make the alloy potentially suitable for a number of automotive applications.