【摘要】 采用放电等离子烧结制备添加微量稀土元素的钛铝合金，研究稀土元素Yb、Ce对钛铝合金高温抗氧化性能的影响。利用金相显微镜、扫描电子显微镜和X射线衍射仪分析钛铝合金的组织结构、微观形貌和物相组成，通过高温氧化实验分析合金的高温抗氧化性能。结果表明：经放电等离子烧结制备的钛铝合金的相对密度最高可达99%。800℃高温氧化后的氧化动力学曲线均近似遵循抛物线规律；经过100h的高温氧化处理后，Ti-45Al、Ti-45Al-0.3Yb₂O₃和Ti-45Al-0.3CeO₂三种合金的质量增重分别为14.63g·m^-2、7.02g·m^-2、8.19g·m^-2。添加稀土元素的钛铝合金的高温抗氧化性能明显得到改善，其中添加Yb的钛铝合金的高温抗氧化性能提高约1倍。钛铝合金的氧化产物均具有典型层状结构，最外层为TiO₂，第二层为TiO₂+Al₂O₃混合氧化物。更多还原

【Abstract】 TiAl alloys added with the trace rare earth elements were prepared by spark plasma sintering（SPS）. The effects of rare earth elements Yb and Ce on the high temperature oxidation resistance of TiAl alloys were investigated. The microstructure,morphology, and phase composition of TiAl alloys were analyzed by metallographic microscope, scanning electron microscope, and Xray diffraction. The high temperature oxidation resistance of the alloys was studied by high temperature oxidation experiment. The results show that the relative density of TiAl alloys prepared by SPS is up to 99%. The oxidation kinetics curves of 800 ℃ high temperature oxidation approximately follow the parabolic rule. After the high temperature oxidation at 800 ℃ for 10 h, the mass gain of Ti-45Al, Ti-45Al-0.3Yb₂O₃, and Ti-45Al-0.3CeO₂ are 14.63 g·m^-2, 7.02 g·m^-2, and 8.19 g·m^-2, respectively. The high temperature oxidation resistance of the TiAl alloys with the rare earth elements addition is obviously improved, and the high temperature oxidation resistance of Ti-45Al-0.3Yb₂O₃ is increased by about 1 time compared with that of Ti-45Al. The oxidation products of TiAl alloys have the typical layered structure, the outermost layer is TiO₂, and the second layer is TiO₂+Al₂O₃ mixed oxide.更多还原