热处理对Ni-SiC镀层表面形貌和性能的影响

Effects of heat treatment on the microstructure and performance of Ni-SiC coatings

采用直流电镀、脉冲电镀和超声波-脉冲电镀方法制备Ni-SiC镀层,研究热处理温度对Ni-SiC镀层表面形貌、显微硬度以及电化学腐蚀性能的影响。结果表明:经过200℃的热处理后,超声波-脉冲电镀法获得的镀层,其金属晶粒最细密,镀层表面更加光滑;热处理温度在300℃,直流电镀法、脉冲电镀法和超声波-脉冲电镀法制备的镀层显微硬度达到最大值,分别为884HV,902HV,915HV;超声波-脉冲电镀法制备的Ni-SiC镀层耐腐蚀性能最好,而直流电镀法制备的镀层耐腐蚀性能最差。

Ni- SiC coatings were prepared by DC plating, AC plating and ultrasonic- AC plating. The surface morphology, microhardness and corrosion resistance were investigated. The results show that the coating obtained by uhrasonic-AC plating has fine metal grains and smooth surface when the temperature is 200 ℃. And when the temperature is 300 ℃, the hardness of Ni -SiC coatings prepared by DC plating, AC plating and uhrasonic-AC plating is 884HV, 902HV and 915HV, respectively. The corrosion resistance of Ni-SiC coatings prepared by uhrasonic-AC plating is the best, and that obtained by AC plating is the worst.