添加稀土元素对Ni-P/PVDF化学复合镀层耐蚀性的影响

在化学镀Ni-P/PVDF合金镀液中添加稀土元素Y³⁺和La³⁺制备Ni-P/PVDF(RE)复合镀层，用电化学腐蚀测试系统测试复合镀层的耐蚀性，研究了稀土元素的添加量对镀层耐蚀性能的影响。结果表明，在基础镀液中加入适量稀土元素后，所获得的Ni-P/PVDF(RE)复合镀层的晶粒较Ni-P/PVDF镀层更为细小，表面更加均匀和致密；镀层的耐蚀性随着稀土元素加入量的增加呈现先增强后减弱的趋势；在稀土元素的添加量为0.1g/L时，复合镀层的耐蚀性最好。在PVDF微粒和稀土元素的共同影响下，进一步提高Ni-P/PVDF(RE)镀层的耐蚀性。

EFFECT OF RARE EARTH ON CORROSION RESISTANCE OF ELECTROLESS Ni-P/PVDF PLATINGS

Ni-P/PVDF（RE） composite platings were deposited by adding rare earth elements Y³⁺ and La³⁺ into electroless Ni-P/PVDF alloy baths.The effects of rare earth content on corrosion resistance were estimated by electrochemical polarization measurement.The results indicate that at the proper rare earth content,the surface morphology of the electroless Ni-P/PVDF（RE） plating is more uniform and denser than that of Ni-P/PVDF plating.The corrosion resistance of the coatings increases at low rare earth content,and then decreased with the increase of its content.The optimum content of rare earth in plating bath is 0.1 g/L. Under the synergetic effect of rare earth and PVDF particles,the corrosion resistance of the Ni-P/PVDF（RE） plating is enhanced.