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Aluminum (Al)–rich titanium (Ti)–Al alloyed coating was fabricated on the surface of TC4 Ti alloy to improve the high-temperature stability of TC4 Ti alloy by means of arc-added glow discharge plasma technology. Microstructure, room-temperature properties and long-term high-temperature oxidation behavior of the alloyed sample were investigated. The results show that a uniform and compact Ti–Al alloyed coating with about 30[Formula: see text][Formula: see text]m thickness formed on the surface of TC4 Ti alloy. Microhardness and room-temperature wear resistance of the alloyed sample improved significantly. Long-term oxidation behaviors of the samples in air at 800[Formula: see text]C for 1000[Formula: see text]h show that the mass gain of the alloyed sample was 0.3686[Formula: see text]mg/cm2, while that of the substrate was 18.2095[Formula: see text]mg/cm2. Arc-added glow discharge plasma aluminizing improved high-temperature oxidation resistance of TC4 Ti alloy significantly.

Ti–Al alloyed coating reinforced by nitrides was fabricated by laser surface alloying technique to improve mechanical properties and high temperature oxidation resistance of Ti–6Al–4V titanium alloy. Microstructures, mechanical properties and high temperature oxidation behavior of the alloyed coating were analyzed. The results show that the alloyed coating consisted of Ti3Al, TiAl2, TiN and Ti2AlN phases. Nitrides with different morphologies were dispersed in the alloyed coating. The maximum microhardness of the alloyed coating was 906[Formula: see text]HV. The friction coefficients of the alloyed coating at room temperature and high temperature were both one-fourth of the substrate. Mass gain of the alloyed coating oxidized at 800[Formula: see text]C for 1000[Formula: see text]h in static air was [Formula: see text][Formula: see text]mg/mm2, which was 1/35th of the substrate. No obvious spallation was observed for the alloyed coating after oxidation. The alloyed coating exhibited excellent mechanical properties and long-term high temperature oxidation resistance, which improved surface properties of Ti–6Al–4V titanium alloy significantly.