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利用磁控反应溅射的方法在Ti₃Al基合金表面制备了两种不同铝含量的Cr_0.82Al_0.18N与Cr_0.53Al_0.47N涂层，测试了这两种涂层在800 ℃（Na₂SO₄ + 25 mass %K₂SO₄）熔融盐膜下的热腐蚀动力学，并采用X射线衍射仪和带能谱的扫描电镜分析腐蚀产物相组成以及微观结构。结果表明，两种涂层均可降低Ti₃Al基合金的热腐蚀速率；涂层热腐蚀产物主要为具有保护性的Cr₂O₃和θ-Al₂O₃混合氧化膜，θ-Al₂O₃的含量随着涂层中Al含量上升递增；和-θ-Al₂O₃相比，Cr₂O₃在熔融硫酸盐中的稳定性更好，Cr_0.82Al_0.18N涂层抗热腐蚀性能优于Cr_0.53Al_0.47N涂层。

Cr_0.82Al_0.18N and Cr_0.53Al_0.47N coatings were deposited on a Ti₃Al based alloy by reactive magnetron sputtering method. Hot corrosion of these two coatings in 75 mass % Na₂SO₄+25 mass % K₂SO₄ molten salt at 800 ℃ was performed in a Setsys 16/18 thermoanalyzer. The phase compositions of the corrosion products were identified by X-ray diffractometer (XRD). Both the surface and cross-sectional morphologies of the samples were observed by a scanning electron microscope (SEM). The results showed that both Cr_0.82Al_0.18N and Cr_0.53Al_0.47N can reduce the hot corrosion rate of the Ti₃Al based alloy and their hot corrosion resistance decreases with increasing aluminum content; the main corrosion products of the coatings are Cr₂O₃ and θ-Al₂O₃ and the amount of θ-Al₂O₃ in the corrosion products is proportional to the Al content in the coating. The better hot corrosion resistance of Cr_0.82Al_0.18N coating can attribute to the high stability of Cr₂O₃ in the molten salt.