Aluminum alloy piston, for an internal combustion engine, has a top surface depression with an annular strengthened region of strength decreasing with increasing distance from the piston pin bores

摘要

An aluminum alloy piston, has a top surface depression having an annular strengthened region (15) of strength decreasing with increasing distance from the piston pin bores. An internal combustion engine piston comprises: (a) an aluminum alloy base with a top surface depression acting as the combustion chamber; (b) a lug (9) extending downwards from the base and including aligned piston pin bores with a common axis (100); and (c) an annular strengthened region (15) extending around the peripheral edge (14) of the depression and having a mechanical strength which decreases with increasing distance from the piston pin bore axis (100). An Independent claim is also included for production of the above piston. Preferred Features: The strengthened region (15) is formed by electron beam melting of a copper-containing fusible ring.