Retainer

摘要

A brass is a base material, and a material containing Mn and Si is cast to make a ring material. A metallic structure in the cross section of the ring material is under a condition where an intermetallic compound Mn5Si3 is uniformly and finely scattered and precipitated in the base material (brass composed of alpha - and beta -phases). A machined retainer provided by machining said material has an excellent sizing precision, sound effect and impact resistance.