DE-LEADING TREATMENT METHOD FOR LEAD-CONTAINING COPPER ALLOY AND DE-LEADING CORED WIRE USED IN SAID METHOD

摘要

A copper alloy such as brass and bronze centered on rod products in which machinability is mainly required contains a certain amount of lead. The scrap of these products has been recycled at a high rate. A lead-removing step is indispensable for recycling the scrap of these products for low-lead products, and development of lead-removal techniques is urgently necessary. It is known that a material containing metal element calcium exhibits an effect in removing lead in a copper alloy, and since there are differences in the specific gravity and the melting point between a de-leading agent and a copper alloy, a de-leading method at a practical mass production level is required. In order to solve this problem, for the purpose of de-leading treatment of a copper alloy molten metal, there is provided a cored wire for lead removal characterized in that a metal band which does not affect the components of a copper alloy molten metal is used as a sheath material; a single de-leading agent and/or a de-leading coagent such as an aggregation/floatation agent for a Pb-Ca compound required for a step is used as contents; and physical properties that endure mechanical and continuous feed by a cored wire feeding device are provided.