The study of refractory Ta10W and non-refractory Ni60A coatings deposited by wire electrical explosion spraying

In conventional thermal spraying processes, it is difficult to employ one type of coating process to economically spray materials having greatly different melting points. In this study, wire electrical explosion spraying(WEES) was applied to prepare refractory Ta10W and non-refractory Ni60A coatings by using a self-designed WEES device. The coating microstructure, deposition efficiency and coating thickness, as well as the adhesive strength of both coatings were investigated. A uniform and dense Ta10W coating with the phase of Ta, Ta2N, and FeTaO4 can be obtained when the energy density was 151.6 J/mm3, while the uniform and dense Ni60A coating made up of FeNi and SiO2 phase was got at the energy density of 72.7 J/mm3. The maximum deposition efficiency of Ta10W and Ni60A were 53% and 47% respectively. The thickness increment of both coatings decreased with the explosion frequency. The critical load Lc in the scratch test can be regarded as a criterion of the adhesive strength, the average critical load of Ta10W was greater than 50 N, while the Ni60A was 38.3 N. Through developing a high-efficient spray device and choosing the appropriate process parameter, especially a suitable energy density, the WEES will be capable to produce the commercially available coatings with greatly different melting points.