Preparation process and friction-abrasion property of TiN/TiB2 multi-permeation layer
(1.Guilin University of Electronic Polytechnic, Guilin 510014, China2.太原理工人学表面工程研究所,太原030024)
Abstract: A new technique was introduced that TiN permeation layer composed of diffusion and deposition layer was synthesized on the surface of Q235 steel using plasma point discharge and hollow cathode effect, and then TiB2 film was deposited (PVD) on newly-formed surface to create TiN/TiB2 multi-permeation layer. The thickness of this multi-permeation layer is above 10μm and the composition and hardness have graded distribution. It has metallurgical bonding with substrate and the bonding strength is high without any spallation phenomenon. In addition comparative research, between TiN/TiB2 multi-permeation layer and TiB2 film which is directly deposited (PVD) on Q235 steel substrate, on surface appearance, microhardness and friction-abrasion property was carried out. The results show that both of surface consist of uniform, compact and fine cellular structure. Surface microhardness of TiN/TiB2 multi-permeation layer is higher, reaching HV2600; but its average friction coefficient is lower, abrasion crack is shallower and wear resistance is better.
Key words: TiN/TiB2; point discharge; hollow cathode effect; multi-permeation layer; friction-abrasion