In the field of high performance engines (i.e. motorbikes, sports applications,…) the modern state of art requires the use of drop-forged pistons.
These components are made with alloys obtained from the inverse extrusion of casted aluminum billets. The alloys used for these pistons are Al-Si alloys which unlike those used for casting pistons allow to achieve a finer structure which results in better mechanical properties.
The use of forged pistons, in addition to allowing to obtain more resistant alloys, allows to have thinner resistant sections with a considerable advantage in terms of weight.
A special feature that can be employed on the forged pistons to limit the excessive wear of the first groove is the application of a coating of hard anodizing.
Also in the forged pistons the application of coatings based on graphite is provided to limit the friction between piston and cylinder.