FREE-CUTTING STAINLESS STEEL AND PROCESS FOR PRODUCING THE SAME

摘要

The present invention relates the free-cutting stainless steel that have not only of excellent machinability but also environment-friendliness and corrosion resistance and excellent mechanical property and methods of manufacturing free-cutting stainless steel. Free-cutting stainless steel produced by adding a free-cutting additive is characterized in that the free-cutting additive thereof is h-BN (hexagonal boron nitride) particles dispersed and precipitated homogeneously in the stainless steel. A method of manufacturing free-cutting stainless steel produced by adding a free-cutting additive is characterized in that free-cutting stainless steel where h-BN particles are precipitated is heated to dissolve the h-BN particles into steel matrix, quenched and subsequently tempered to disperse and precipitate h-BN particles homogeneously again as free-cutting additive or in that free-cutting stainless steel where h-BN particles are precipitated is heated to dissolve the h-BN particles into steel matrix and subsequently subjected to slow cooling to disperse and precipitate h-BN particles homogeneously again.