表面技术2017，Vol.46Issue(7)：32-38,7.DOI:10.16490/j.cnki.issn.1001-3660.2017.07.006
纳米Al2O3对电刷镀Ni-P复合镀层耐蚀性能的影响
Effect of Nano-Al2O3 on Corrosion Resistance of Ni-P Composite Coating by Electro-brush Plating
摘要
Abstract
The work aims to extend service life and improve corrosion resistance of ink scraper. Ni-P coating and Ni-P/Al2O3 composite coating co-depositing nano Al2O3were prepared in electro-brush plating method.Corrosion behavior of Ni-P coating and Ni-P/Al2O3 composite coating in 3.5% NaCl solution by means of potentiodynamic polarization curve, corro-sion weight loss curve and AC impedance spectroscopy. Microstructure and composition of the two coatings before and after corrosion were analyzed with scanning electron microscope (SEM) and energy-dispersive spectroscope (EDS). Corrosion poten-tial of Ni-P coating, which was codeposited with nano-Al2O3, shifted positively from?0.318 V to?0.237 V, and self-corrosion current density decreased from 6.04μA to 5.75μA since standard potential of namo Al2O3was more positive than that of Ni, uniform distribution in coating led to positive shift of corrosion potential and formed corrosion microbattery with Ni-P alloy as anode and Al2O3 particle as cathode, and thereby promoted anodic polarization. After codeposition of nano Al2O3, the electro-chemical reaction resistanceRct of Ni-P/Al2O3 increased from 1.066×104?·cm2 to 2.864×104?·cm2, double-layer capacitance Cdl decreased from 43.45μF/cm2 to 27.36μF/cm2. Compared with the Ni-P coating, the surface structure of the Ni-P/Al2O3 composite coating was more compact and the defects were less. In the process of corrosion, the phosphorus and oxygen ele-ments were enriched on the surface of Ni-P coating to form a passive film which inhibited the corrosion. Codeposition of Al2O3 nanoparticles can effectively improve corrosion resistance of Ni-P coating.关键词
电刷镀/纳米Al2O3/耐腐蚀性能/显微结构/钝化膜/均匀腐蚀Key words
electro-brush plating/nano-Al2O3/corrosion resistance/microstructure/passive film/uniform corrosion分类
矿业与冶金引用本文复制引用
周宏明,胡雪仪,李荐..纳米Al2O3对电刷镀Ni-P复合镀层耐蚀性能的影响[J].表面技术,2017,46(7):32-38,7.基金项目
清远市科技计划项目(2015D009) （2015D009）
清远市清城区科技计划项目(2015B04)Supported by Science and Technology Project of Qingyuan City (2015D009), Science and Technology Projects of Qingcheng District (2015B04) （2015B04）
