Reinforcing aluminium alloy piston ring groove - by fusing ring portion and adding constituent alloying to fused part

摘要

An Al alloy piston ring groove is reinforced by: fusing the piston body to a certain depth in the zone where a ring groove is to be cut; simultaneously introducing an alloying addn. (I) into the fused piston alloy; and cutting the ring groove in the periphery of the resulting annular wear-resistant weld. In a pref. method, the fusion depth is 0.3-1.3 X the final depth of the ring groove. (I) is pref. Ni or Ni/Cr alloy. Used esp. for top ring groove reinforcement in prod. of Al alloy pistons 210 mm in dia. for i.c. engines. Method is simpler than prior art and provides enhanced bonding strength between the weld and the piston body; a uniform weld is achieved with uniform distribution of alloy additive.