Oxidation of double-glow plasma chromising coating on TC4 titanium alloys

• Published in: Corrosion science Vol. 66; pp. 43 - 50
• Main Authors: Wei, Dong-Bo, Zhang, Ping-Ze, Yao, Zheng-Jun, Liang, Wen-Ping, Miao, Qiang, Xu, Zhong
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.01.2013; Elsevier
• Subjects: A. Titanium alloy; Alloys; Applied sciences; B. High-temperature oxidation; B. Metal coating; C. Diffusion; Chromium; Coating; Corrosion; Corrosion environments; Diffusion; Exact sciences and technology; Metallic coatings; Metals. Metallurgy; Multilayers; Oxidation; Production techniques; Surface treatment; Titanium; Titanium base alloys; B. High-temperature oxidation; B. Metal coating; C. Diffusion; A. Titanium alloy; Plasma; Temperature; Chromizing; High temperature; Surface treatment; Metal coating; Oxidation; Diffusion; High temperature corrosion
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/j.corsci.2012.08.063

► A chromising coating was prepared on titanium alloys by plasma alloying technology. ► The isothermal oxidation of the chromising coating was studied at 650–850°C. ► The Ti–Cr mutual diffusion layer of chromsing coating prevented the intrusion of O. ► A multi-layer structure with Cr2O3, TiO2, and Al2O3 was formed during oxidation. ► Ti, Al, and Cr diffused predominantly outward during oxidation. Double-glow plasma surface chromising was performed on TC4 (Ti–6Al–4V) alloys, and the isothermal oxidation behaviour of TC4 was investigated at 650, 750, and 850°C. The surface treatment caused the formation of a Ti–Cr mutual diffusion layer beneath the alloy surface. The chromising coating consisted of Cr, Cr1.97Ti1.07, and CrTi4. During oxidation, Cr, Ti, and Al diffused outward to form multi-layer oxide films, which prevented the diffusion of oxygen.