Effect of Mg–Re complex treatment on eutectic carbides in bearing steel

ABSTRACT

Effect of an Mg–Re complex treatment on eutectic carbides in bearing steel has been studied. Results show that the number, and the average maximum size of carbides tend to decrease and then increase with the increase in Mg content. When the Mg content is low, the addition of Re is not conducive to the refinement of carbides; When the Mg content is high, the number and size of carbides decreases with the increase of Re. The main reason for the refinement of carbides by Mg is that the diffusion of Mg hinders the diffusion of C and Cr, so that the formation and growth of carbides are inhibited. A large number of MgS-MnS can induce the precipitation of carbides, which also leads to the dispersion of carbides. While the Re‑Mg complex treatment, the inclusions containing Re and segregation of Mg is the main reason for the refinement of carbides.

KEYWORDS:

• Bearing steel
• Mg
• Re
• eutectic carbide
• inclusion

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by National Natural Science Foundation of China [grant number 51574001/51504001] and Key Program in the Youth Support Plan in Universities of Anhui Province of China [grant number gxyqZD2017034].