Fiber-reinforced piston for internal combustion engines and associated method of construction

A fiber reinforced piston for an internal combustion engine comprising a top land and a ring region provided with an uppermost ring groove, said top land and said ring region being defined by a reinforced part of the piston formed by a matrix metal reinforced with inorganic fibers, said reinforced part of the piston being circularly symmetrical around an axis of the piston and forming an annulus around a top portion of the piston, said reinforced part having a cross-section, in a plane containing the axis of the piston, of substantially rectangular shape except for the uppermost ring groove, said piston having an upper crown surface, said reinforced part being formed as a cylindrical shell having an upper radial surface which is continuously formed in said upper crown surface, a lower radial surface, an inner cylindrical surface joining said upper and lower radial surfaces and an outer cylindrical surface having a radius equal to that of the outer cylindrical surface of the piston, said uppermost ring groove having an upper annular side wall surface, a lower annular side wall surface and an annular bottom surface connecting said upper and lower annular side wall surfaces, said inner cylindrical surface of the reinforced part having a smaller radius than that of the annular bottom surface of the uppermost ring groove, said reinforced part extending in the axial direction of the piston from the upper crown surface to a postion below said lower annular side surface of the uppermost ring groove, whereby said uppermost ring groove is totally defined within said reinforced part.