IMPROVEMENT OF HIGH-TEMPERATURE OXIDATION RESISTANCE OF TiAl-BASED ALLOY BY SILICONIZING TREATMENT
表面渗硅处理提高钛铝基合金高温抗氧化性

Siliconizing treatment on TiAl-based alloy was conducted by Al-Si molten alloy. The interfacial reactions have occured between the TiAl-based alloy and the Al-Si molten alloy, resulted in the formation of phases mainly composed of elements of Si, Ti and Al. After isothermal oxidation at 1173 K for 100 h, these Si-Ti-Al phases are transformed into compacted oxides of Si-Ti-Al-O. Moreover, interfacial reactions forming compounds of Ti-Si and TiAl2. The high-temperature oxidation resistance of the TiAl-based alloy is greatly improved by the siliconizing treatment. For the sample siliconized at 1153 K, part of the Si-Ti-Al compound directly transformed into Ti-Si compound during the isothermal oxidation.