Patent ID: 6413330
Filing Date: 2002-07-02
Classification: C22C,C22F

Abstract:
A lead-free free-cutting copper alloy, consisting essentially of 69 to 79 percent, by weight, of copper; from 3.0 up to and including 4.0 percent, by weight, of silicon; and the remaining percent, by weight, of zinc, wherein the percent by weight of copper and silicon in the copper alloy satisfy the relationship55&lE;Xâˆ’3Y&lE;70, whereinX is the percent, by weight, of copper, and Y is the percent, by weight, of silicon; and the copper alloy has a metal construction comprising multiple phases integrated to form a composite phase, wherein the composite phase is an &agr; phase matrix having a total phase area comprising not more than 5% of a &bgr; phase, and 5-70% of the total phase area is provided by at least one phase selected from the group consisting of a &ggr; phase, a &kgr; phase, and a &mgr; phase.