A Ta-modified layer was prepared on γ-TiAl by double-glow plasma surface metallurgy technique. Based on the results of high-temperature oxidation tests at 700, 800, and 900 °C, we studied the morphology, depth profile, and phase of γ-TiAl and Ta-modified layer by scanning electron microscopy, energy spectrum analysis, and X-ray diffraction analysis. Results showed that the Ta-modified layer was tightly bonded to the substrate without voids and cracks, consisting of the α-Ta outer layer and inner diffusion layer. It was found that the isothermal oxidation kinetic curves of the TiAl with the Ta-modified layer followed the parabolic rate law. Ta element promoted the diffusion of Al and formation of uniformly mixed Al2O3/Ta2O5 films, which prevented the inward diffusion of oxygen and help to the improved high-temperature oxidation resistance.

中文翻译：

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双辉等离子钽合金在γ-TiAl上的高温氧化

采用双辉等离子体表面冶金技术在γ-TiAl上制备了Ta改性层。基于 700、800 和 900 °C 的高温氧化试验结果，我们通过扫描电子显微镜、能谱分析和 X -射线衍射分析。结果表明，Ta改性层与基体紧密结合，无空隙和裂纹，由α-Ta外层和内扩散层组成。发现具有Ta改性层的TiAl的等温氧化动力学曲线遵循抛物线速率定律。Ta元素促进了Al的扩散，形成了均匀混合的Al2O3/Ta2O5薄膜，阻止了氧的向内扩散，有助于提高高温抗氧化性。