【摘要】 利用扫描电镜(SEM)、X射线衍射(XRD)和腐蚀电化学测试研究了镀液中SiC含量对化学镀Ni-P-SiC复合镀层结构和耐蚀性能的影响。结果表明,随着镀液中SiC含量的增加,镀层沉积速率和镀层中SiC共沉积量呈现先增加后降低的趋势,镀层中P含量和沉积胞状颗粒尺寸逐渐降低。电化学测试结果表明,镀层中SiC共沉积量的变化不影响镀层腐蚀反应机理,但是镀层耐蚀性随SiC共沉积量的增加而降低。结构分析显示,NiP-SiC镀层致密性良好,基本完全覆盖了镁合金基体。更多还原

【Abstract】 The effect of SiC content in plating bath on the surface morphology and corrosion resistance of electroless plated Ni-P-SiC composite coatings on AZ91D magnesium alloy was investigated by means of SEM, XRD and electrochemical corrosion measurements. The results indicate that the deposition rate and SiC content in the Ni-P-SiC composite coatings increase firstly and then decrease afterwards with the increase of SiC content in the plating bath. The P content and grain size of the composite coatings decrease with the increase of SiC content in the plating bath. The effect of the codeposited SiC on the corrosion process of Ni-P-SiC composite coatings in 3.5%NaCl solution is found negligible, however the corrosion resistance of the Ni-P-SiC composite coatings decreases with the increase of SiC content in the coatings.更多还原