采用料浆法与真空扩散相结合的方法在1Cr18Ni9Ti不锈钢表面制备Al-Si渗层,并研究其在1 000 ℃空气中的氧化行为.利用带能谱的扫描电镜( SEM/EDS)对氧化产物的显微组织形貌进行观察与分析.结果表明:无涂层不锈钢在1 000 ℃空气中的氧化动力学曲线遵循直线规律,表面产生了疏松、不完整的氧化膜,且局部存在裂纹,与基体的黏结性能差,经EDS分析可知氧化膜的主要成分为Cr2 O3 以及Fe2 O3 等氧化物,抗氧化性能差.渗Al-Si涂层不锈钢在氧化前期比无涂层不锈钢氧化增重大,主要是由于产生了Al2 O3 保护性膜,氧化后期氧化增重明显降低,氧化动力学曲线呈现抛物线规律,并且产生了Al2 O3 保护性膜,厚度约为8 μm,与基体的黏附性能好,可有效阻止氧化反应的进一步发生,提高不锈钢的抗氧化性能.%Al-Si coating was prepared on 1 Cr18 Ni9 Ti stainless steel by slurry process and vacuum diffu-sion. The oxidation behaviour of Al-Si coating has been studied at 1 000℃ in air atmosphere. Sectionmor-phology and composition of the oxidation product were studied by the means of SEM and EDS. The re-sults show that loose oxidation filmis formed on the no coating stainless steel, which has poor bonding properties of the matrix,and there are some partial cracks in it. The main component of oxidation film is Cr2 O3 and Fe2 O3 complex oxide by analysis of EDS, and the oxidation behaviour is not well. Due to formed protected oxidized film Al2 O3 , oxidation mass gain of the stainless steel with Al-Si coating is lar-ger than uncoated in the early stage of the oxidation,and the oxidation mass gain fitted to the parabolic law in the after period of the oxidation,because the protected oxidation film can prevent the occurrence of further oxidation,and stainless steel with Al-Si coating has better oxidation behaviour.
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