研究了激光增材制造Ti-48Al-2Nb-2Cr金属间化合物在850 ℃温度时的氧化增重和组织变化，分析了铸态和激光沉积态试样氧化行为的区别，并揭示了其氧化机理。结果表明，当氧化时间相同时，沉积态试样的氧化增重速率明显小于铸态的。经60 h氧化后，铸态试样氧化膜和基体完全剥离，而沉积态试样氧化膜与基体局部结合较好。沉积态和铸态试样表面的氧化膜组成不同，前者为TiO2/Al2O3/基体，后者为TiO2/Al2O3/TiO2+Al2O3/基体。

The microstructure change and oxidation weight increase of Ti-48Al-2Nb-2Cr intermetallic compounds prepared by laser additive manufacturing at the temperature of 850 ℃ are studied, the difference of oxidation behavior between the as-deposited and the as-casted specimens is analyzed, and their oxidation mechanisms are disclosed. The results show that, when the oxidation time is same, the oxidation weight increase rate of the as-deposited specimen is obviously smaller than that of the as-casted specimen. After oxidation of 60 h, the oxidation layer of the as-casted specimen is completely delaminated from the alloy matrix, while the oxidation layer of the as-deposited specimen is well combined locally with the matrix. The compositions of oxidation films of the as-deposited and those of as-casted specimens are different, the former is TiO2/Al2O3/matrix and the latter is TiO2/Al2O3/TiO2+Al2O3/matrix.