Iron species preform

摘要

An iron species preform (1) for forming a metal matrix composite is inserted in an aluminum species alloy member to be cast-in. The aluminum species alloy member has bearing faces having a section in a semicircular arc shape. An inner peripheral face (11) of the iron species preform (1) is provided with a plurality of inner side grooves (21). The inner side groove (21) includes flat portions (23) and groove bottom portions (24) continuous to two end edges (22) continuous to the inner peripheral face (11) and opposed to each other. In a cast-in step, shrinkage in a peripheral direction accompanied by solidifying a molten aluminum species alloy is uniformly received by the respective inner side grooves (21), movement in the peripheral direction is restrained, a clearance at an interface can be prevented from being brought about, so that a cast-in performance is excellent, and stable bonding strength and close contact of the interface can be ensured.