Regular Article

Modification of sulfide by Te in Y1Cr13 free-cutting stainless steel

Center for Advanced Solidification Technology (CAST), School of Materials Science and Engineering, Shanghai University, Shanghai 201900, PR China

^* e-mail: fujianxun@shu.edu.cn

Received: 23 October 2019
Accepted: 23 December 2019

Abstract

Te is an alloy element which is capable of improving the morphology of sulfide in free-cutting steel. In this paper, the effect of modification and mechanism of action of Te on sulfide was studied by addition of various Te masses to the Y1Cr13 free-cutting stainless steel. The results revealed that the typical sulfide in Y1Cr13 was MnS, and when Te content exceeded 170 ppm, it was transformed into a solid solution and precipitated as MnTe in Te–Mn–S solution. The solid solution of Te in MnS coarsened MnS and improved its hardness. The precipitated MnTe enveloped MnS and absorbed the rolling stress in high temperature. Both forms of Te improved the morphology of MnS, promoted the transition from type II to type I and III as the Te content increased. The effect of the modification was good, and it was mainly ascribed to the precipitation of MnTe.