STEEL FOR MACHINE STRUCTURE EXCELLING IN MACHINABILITY AND STRENGTH PROPERTY

摘要

A steel for machine structure that in a wide range of cutting speed, exhibits appropriate machinability, and that simultaneously has high impact performance and high yield ratio. The steel for machine structure is one excelling in machinability and strength property, comprising, by mass, 0.1 to 0.85% C, 0.01 to 1.5% Si, 0.05 to 2.0% Mn, 0.005 to 0.2% P, 0.001 to 0.15% S, over 0.05 to 0.3% total Al, less than 0.0150% Sb (including 0%), 0.0035 to 0.020% total N wherein solid solution N is limited to 0.0020% or less, and the balance Fe and unavoidable impurities.