Study on wear resistance of TiN multi-permeation layer using glow plasma surface alloying

In this paper, a new technique has been firstly introduced that TiN permeation layer composed of diffusion and deposition layer was synthesized on the surface of carbon steel, mainly according to plasma point discharge, hollow cathode effect and reactive vapor deposition technique, and then TiN film was deposited (PVD) on this surface to form TiN multi-permeation layer. The thickness was above 10 μm, and all the composition and structure were graded distribution. And it also was metallurgical bonding with substrate and cohesion force was better without any spallation phenomenon. Subsequently comparative research between TiN permeation layer and TiN multi-permeation layer on surface appearance, phase structure, microhardness and wear resistance were investigated. The results show that both surface appearances consist of compact and fine cellular structure and color are golden. From X-ray diffraction results the surface of multi-permeation layer is pure TiN layer and the diffraction peak of (200) crystal face is the strongest having obvious preferred orientation. Surface microhardness of TiN multi-permeation layer is higher, reaching about 2500 HV. But also the abrasion curve is more stable, mean friction coefficient is lower, and abrasion crack is also narrower, compared to TiN permeation layer. So the wear resistance is better than that.