热处理对HVOF WC-17Co涂层组织结构及耐磨性能的影响

采用超音速火焰喷涂技术在42CrMo钢表面制备了硬质WC-17Co耐磨涂层，分别在500，700，900，1 100 ℃保温1 h进行热处理，进而研究了热处理温度对涂层微观组织、相组成、硬度以及耐磨性能的影响。实验结果表明：随着热处理温度的升高，W2C相逐渐减少而非晶态的Co发生再结晶生成Co3W3C和Co6W6C；硬度呈现先升高后降低的趋势，700 ℃热处理后，WC硬质相增多，硬度最高；喷涂态WC-17Co涂层的耐磨性较差，900 ℃热处理后，析出的Co6W6C细小且弥散均匀分布，涂层的磨损量最小、耐磨性最好。

Influence of heat treatment on microstructure and wear resistance of HVOF WC-17Co coatings

The hard WC-17Co coatings were prepared on 42CrMo steel by means of High Velocity Oxygen Flame (HVOF) technique.The coatings were treated at different temperature and the influence of heat treatment temperature on the microstructure,micro-hardness and wear resistance of WC-Co coatings was investigated in this study.The results show that,as the temperature increases,the W2C phase decreases and the amorphous Co recrystallizes new Co3W3C and Co6W6C phases,and the micro-hardness of the coating first increases and then decreases.The micro-hardness reaches the highest after heat treatment at 700 ℃.The coating possesses the smallest wear loss rate and best wear resistance after heat treatment at 900 ℃,which results from the dispersive Co6W6C phase in the coating.