脉冲电沉积RE-Ni-W-B-PTFE-Al2 O3复合镀层性能的研究

高性能复合镀层具有优良的耐磨、耐蚀性能,能满足工业生产对材料性能的要求.研究了脉冲电沉积RE-Ni-W-B-PTFE-Al2O3复合镀层的成分、形貌及性能.结果表明:脉冲电流及Al2O3固体颗粒能明显提高RE-Ni-W-B-PTFE-Al2O3复合镀层中W和B的含量;与直流电沉积相比,脉冲电沉积RE-Ni-W-B复合镀层的表面裂纹已明显减小,但裂纹仍存在,当Al2O3耐磨颗粒及PTFE减摩微粒嵌入RE-Ni-W-B复合镀层中以后,在SEM 400倍下观察,RE-Ni-W-B-PTFE-Al2O3镀层已不存在裂纹, 而且镀液中Al2O3颗粒含量越多,晶粒就越细;此外,研究表明,镀液中Al2O3颗粒含量增加, RE-Ni-W-B-PTFE-Al2O3复合镀层镀态硬度增加,磨损率降低.

Properties of Pulse Electrodeposited RE-Ni-W-B-PTFE-Al2O3 Composite Coating

The components, surface morphologies, hardness, and wear resistance of pulse electrodeposited RE Ni W B PTFE Al_2O_3 composite coatings were studied. The results showed that the introduction of pulse current and Al_2O_3 particulates contributed to increase the content of W and B in the RE Ni W B PTFE Al_2O_3 composite coatings. The surface crack of the pulse electrodeposited RE Ni W B coating obviously decreased as compared with that of the DC electrodepositing. The inclusion of Al_2O_3 antiwear particulates and PTFE friction-reducing particulates in the RE Ni W B coating was beneficial to eliminating the surface crack in the composite coating. Besides, the larger the addition amount of Al_2O_3 particulates in the plating bath, the smaller the size of the crystalline grains in the RE Ni W B PTFE Al_2O3_ composite coating. Moreover, the hardness of the RE Ni W B PTFE Al_2O_3 composite coating increased and the wear rate decreased with increasing Al_2O_3 concentration in the plating bath.