Ni-Nb粉末与SiC陶瓷界面润湿特性研究

研究了Ni—Nb金属粉末与SiC陶瓷的界面润湿特性，结果表明，增加Nb含量、升高温度或延长保温时间，系统润湿性均得到改善。对润湿系统界面区域微观结构的SEM、EDS分析表明，由于活性元素Nb的加入，在一定的温度、时间和气氛等条件下，焊料与陶瓷发生相互问的溶解、扩散和反应，其接触界面发生改变，此时测得的润湿角已不是Ni—Nb液滴/SiC陶瓷村底的接触角，而是新生成的固液界面间的接触角。界面区域具有连续结构的Ni-Si化合物的生成对于Ni—Nb／SiC陶瓷体系的润湿起重要作用。

Investigation on the Wettability Between Ni-Nb Powders and SiC Ceramic

This paper dealed with the wettability of SiC ceramic/Ni-Nb system.The results showed that the contact angle decreased with the increase of Nb content.Also,the contact angle decreased with the increasing of the temperature and prolonging of the dwelling time respectively until it reached a stable value.The microstructure and element distribution at the welded area were analyzed by SEM and EDX.The results showed that the wettability was improved by adding Nb element,which induced the interfacial reaction,promotes the dissolve and diffusion between the ceramic and the metallic materials and raises the driving force of the wettability of the system.Being a chemical wetting,the original interface(Ni-Nb/SiC)was replaced by new phases.The Ni-Si compound,which had continuous construction in the welded area,was important in this wetting system.