Combined Effect of Gas Blow Induction Heating Nitriding and Post-Treatment with Fine Particle Peening on Surface Properties and Wear Resistance of Titanium Alloy

Abstract

In order to fabricate a titanium alloy with superior wear resistance and fatigue strength, fine particle peening (FPP) was introduced as a post-treatment after gas blow induction heating (GBIH) nitriding. The surface characteristics of the treated alloy were examined using X-ray diffraction, scanning electron microscopy, laser microscopy and a micro-Vickers hardness tester. GBIH nitriding and post-treatment with FPP formed nitrided layers with high hardness and compressive residual stress at the surface of the alloy within a short period of time. This is due to the diffusion of nitrogen atoms during GBIH nitriding and plastic deformation of the surface layer during FPP. Reciprocating ball-on-disk wear tests were performed to investigate the wear resistance of the surface-treated alloy. The wear resistance of the titanium alloy was improved by the proposed surface treatment compared with samples that were only polished or FPP-treated. This is due to the presence of a nitrogen compound layer with high hardness at the surface. The abrasiveness toward the wear test counter material was also decreased by the combined surface treatment.

Research Progress of Surface Treatment Technologies on Titanium Alloys: A Mini Review

“…The machining and PIB were conducted at 1.5 J/cm 2 in a pulse, which was able to improve the adhesion properties of the titanium alloys for application in the medical field. In the work of Takesue et al [51], nitrided layers with high hardness and compressive residual stress were obtained, which were able to obviously improve the wear resistance and fatigue strength. This was ascribed to the diffusion of nitrogen atoms during nitriding and the fine particle peening.…”