The high carbon bismuth sulfur compound free-cutting steel and its wire rod and the steel wire

摘要

PROBLEM TO BE SOLVED: To provide free-cutting steel excellent in surface quality and having cuttability equal to those of lead free-cutting steel without using lead, to provide a wire rod thereof, and to provide a steel wire thereof.;SOLUTION: High carbon bismuth-sulfur composite free-cutting steel containing, by mass, 0.70 to 1.00% C, ≤0.35% Si, 0.30 to 0.80% Mn, 0.040 to 0.090% S and 0.05 to 0.30% Bi and the balance iron with inevitable impurities is produced. This steel is hot-rolled into a wire rod, and moreover, and the resultant wire rod is cold-worked to produce a steel wire, which is then subjected to parts working. The steel wire is subjected to a baking at need.;COPYRIGHT: (C)2001,JPO