采用熔盐法在钼基体上制备了硅化钼涂层,利用SEM、EDS和XRD等分析了涂层的显微结构、元素分布及物相组成,并研究了硅化钼的生成机制。结果表明:硅化钼是通过反应扩散形成的,涂层由外至内分别为MoSi2、Mo5Si3和基体;当熔盐中Na2SiF6和NaF两种活化剂共存时,涂层的厚度较大,1 000℃保温10h制备的硅化钼涂层的高温抗氧化性能相对较好;涂层厚度随温度的升高和保温时间的延长而增加,但温度的影响比保温时间的更显著。
A molybdenum silicide coating on Mo substrate was prepared by molten salt method.Microstructure,distribution of element and phase composition of the coating were analyzed by means of SEM,EDS and XRD.The formation mechanism of the molybdenum silicide phase was investigated.The results show that the molybdenum silicide coating was formed through reactive diffusion,and the microstructure of the coating was MoSi2,Mo5Si3 and matrix from the outside to the inside.When Na2SiF6 and NaF existed together in the molten salt,the coating had larger thickness.High-temperature oxidation resistance of the molybdenum silicide coating prepared at 1 000 ℃ for 10 h was relatively good.The thickness of coating increased with the increase of temperature and holding time,and effect of temperature on it was greater than that of holding time.