Multiphase films bearing Ti₂AlN by pulse plasma hollow cathode nitriding

Abstract

This study aims to resolve the wear resistance and extend the use of titanium aluminides. A novel method of obtaining multiphase films bearing Ti 2 AlN on the Ti-Al alloys is put forward. The Ti 12x Al x (x50?25, 0?33 and 0?47) alloys were nitrided in a pulse plasma hollow cathode environment at 800-900uC for various durations in a mixture of 50%N 2 and 50%H 2 under pressures of 1?50-3?00 torr. The results show that the nitriding gas pressure has a strong influence on the phase structure of the surface films. The forming phases in the films are mainly composed of Ti 2 AlN and TiN compounds. The presence of Ti 2 AlN in the wear tracks apparently reduces the friction coefficient of the samples. The hardened phase TiN in the film improves the wear resistance of the Ti-33Al alloy.

Plasma Glow Discharge as a Tool for Surface Modification of Catalytic Solid Oxides: A Case Study of La0.6Sr0.4Co0.2Fe0.8O3−δ Perovskite

“…This method is widely used for the modification of steels and alloy surfaces in industries to enhance surface hardness and corrosion properties by introducing plasma nitrogen and carbon into the surface layer. We found that the chemical elements of the hollow metal cathode can also be sputtered off and then deposited onto the specimen's surface [20]. Inspired by this finding, we expect this method is feasible as a tool for surface modification of SOFC materials.…”

Improvement of wear resistance for carburised steel by Ti depositing and plasma nitriding

“…Ti-based-nitrides such as TiN, Ti 2 N and TiN x could be good candidates for protective coating due to high hardness, excellent wear resistance and corrosive resistance [7,8]. The hard coatings have been applied successfully for titanium alloy [9,10], aluminium alloy [11,12], copper alloy [13,14] and steel [15,16]. However, the coating consisted of Ti-based-nitrides on carburised steel have seldom been investigated so far.…”

Oxidation and Decomposition of Ti₂AlN MAX Phase Coating Deposited on Nickel-Based Super Alloy IN718

“…This unusual combination has attracted considerable attention worldwide and makes MAX phases a promising material for wear and high temperature applications. Primarily Ti-based MAX phases Ti 2 AlX have been synthesized using hot pressing and spark plasma sintering [4,5] as well as using several coating techniques such as DC-magnetron sputtering [6][7][8][9][10][11], pulsed magnetron sputtering [12], pulsed cathodic arc [13], pulse plasma hollow cathode nitriding [14], cold spray [15] HVOF [16,17] and air plasma spray [18]. The oxidation and corrosion behavior has taken a centre stage.…”