Superior surface hardening by cyclic-phase-change-diffusion (CPCD): Supersaturation of hard boride in titanium subsurface layer

SCRIPTA MATERIALIA

卷:124

Article

Sarma, B.¹  Chandran, K. S. Ravi¹ 

[1] Univ Utah, Dept Met Engn, 135 South 1460 East Rm 412, Salt Lake City, UT 84112 USA

关键词: Titanium boride;    Kinetics;    Thermal cycling;    Phase change;    Diffusion;    Titanium;    Boron;   

DOI  :  10.1016/j.scriptamat.2016.07.002

来源: Elsevier

【 摘 要 】

This research demonstrates a novel concept of surface hardening, termed cyclic-phase-change-diffusion (CPCD), where cyclic phase transitions were induced at the surface by thermal cycling across the phase transition temperature along with diffusion of surface hardening atoms. Specifically, boron was diffused through the surface of titanium during thermal cycling across the alpha-beta phase transition temperature. The CPCD method is shown to result in an unusually deeper (similar to 125 mu m) and richer boride layer, on titanium, compared that obtained by isothermal diffusion either at the equivalent temperature or at a higher temperature. This concept is quite promising for superior surface hardening of titanium and its alloys. (C) 2016 Elsevier Ltd. All rights reserved.

【 授权许可】

Free