By casting a preformed member (30) composed of a fiber reinforced material into a base material of a piston, a pair of crown reinforcing portions (21) corresponding to respective pin boss portions (15) are formed on a crown portion (2), and the pair of cro...

An insert (12) is prepared and set into a piston main body (PMB) made from an aluminum cast alloy. The insert is then partly recast with piston material and its immediate surroundings (14) are recast in the PMB. The material of the insert has a higher prop...