Method of making a piston for an internal combustion engine

摘要

The present intends to provide a piston for an internal combustion engine which is light-weight and has a high heat resistance strength but can still be manufactured easily. Furthermore, the present invention intends to provide a method of making such a piston. Accordingly, the piston comprises a head portion exposed to a combustion chamber and a skirt portion sliding within a cylinder. The head portion is made of an alloy comprising Al, Fe and Si and the skirt portion is made of an alloy comprising Al, Si, Cu and Mg. Both portions are joined together by forging. The joining interface between the members made of different alloys is designed so as to have a non-flat shape.