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

摘要

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 ℃. The surface treatment caused the formation of a Ti-Cr mutual diffusion layer beneath the alloy surface. The chromising coating consisted of Cr, Cr_(1.97)Ti_(1.07), and CrTi_4. During oxidation, Cr, Ti, and Al diffused outward to form multi-layer oxide films, which prevented the diffusion of oxygen.