TiAlCr涂层对TiAl金属间化合物抗高温氧化性能的影响

EFFECT OF TiAlCr COATING ON OXIDATION RESISTANCE OF TiAl INTERMETALLICS

研究了溅射Ti-50Al-10Cr涂层在800℃～1000℃对TiAl金属间化合物抗高温氧化性能的影响。结果表明,TiAl合金由于形成Al_2O_3和TiO_2的混合氧化物膜而表现出较差的抗高温氧化性能,而TiAlCr涂层由于形成粘附性好的Al_2O_3,膜而大大提高TiAl的恒温及循环氧化性能。经900℃ 1000h长时间氧化,TiAlCr涂层对TiAl合金仍能提供很好的防护,涂层和基材结合良好,无孔洞及裂纹出现,表现出好的涂层-基材相容性。

The effect of a sputtered Ti-50Al-10Cr coating on oxidation resistance of TiAl intermetallic compound was investigated in static air. The bare TiAl alloy exhibited poor isothermal and cyclic oxidation resistance at 800-1000℃ due to the formation of TiO2-based scales which tended to spall during cooling. The sputtered Ti-50Al-10Cr coating could remarkably improve the oxidation resistance of the TiAl alloy by means of the formation of adherent Al2O3 scale. After long-term oxidation (at 900℃ for 1000h), TiAlCr still provided an excellent protection for TiAl alloy and only a slight interdiffusion occurred as a result of the inward diffusion of Cr while no voids were found at the coating/substrate interface. The TiAlCr coating combined better oxidation resistance with its compatibility to substrate than any other conventional aluminide and MCrAlY coatings.