High conductivity copper alloy for semi-solid forming and manufacturing method thereof

Abstract

Disclosed is a copper alloy having high electrical conductivity of at least 70% IACS and a broad solid-liquid two-phase region, capable of being easily subjected to a semi-solid forming process even at various temperatures. The copper alloy is suitable for use in a rotor of small- and medium-sized electric motors. In addition, the prevent invention provides a method of manufacturing the copper alloy for semi-solid forming, including the step of melting a copper-calcium alloy having 0.1-1.5 wt % of calcium and the balance of copper at 1100-1150° C. to form a molten copper-calcium alloy, which is then maintained at 1100-1150° C. for a predetermined time period. Then, the molten copper-calcium alloy is poured into a mold preheated to 100-150° C. and cast to a copper alloy ingot. Thereafter, in order to remove segregation and stress generated upon casting and to convert a dendritic strucutre of a primary copper phase to a globular structure, the copper alloy ingot is subjected to thermomechanical treatment, thereby obtaining the primary copper phase comprising the globular structure suitable for semi-solid forming.

Dependencies are inferred from the claim text.