电沉积方式对Ni-Cr-Mn合金镀层耐蚀性的影响

发布时间：2019-07-19 15:25

【摘要】：采用直流、单脉冲和换向脉冲三种不同电沉积方式在Q235钢表面电镀制备Ni-Cr-Mn合金镀层。利用辉光放电光谱仪、形状测量激光显微系统、Tafel曲线和电化学阻抗谱,研究了电沉积方式对镀层元素含量、沉积速率、3D形貌和耐蚀性的影响。结果表明:按照直流、单脉冲和换向脉冲的顺序,镀层中镍含量减小,铬、锰含量增大,沉积速率先增大后减小,表面粗糙度降低,耐蚀性增强。直流方式制备的镀层表面存在个别较大的颗粒,单脉冲方式制备的镀层表面颗粒大小较为均匀,但仍存在个别较大颗粒,换向脉冲方式制备的镀层总体均匀致密。换向脉冲方式制备的镀层表面粗糙度最低,在3.5%NaCl溶液中,该镀层具有最大的腐蚀电位(-0.305 V)、最小的腐蚀电流密度(7.467×10~(-8)A·cm~(-2))和最大的电荷转移电阻(5972Ω·cm~2),耐蚀性最佳。
[Abstract]:The Ni-Cr-Mn alloy coating was prepared on the surface of Q235 steel by using three different electrodeposition methods of direct current, single pulse and commutation pulse. The effect of electrodeposition on the content of the element, the deposition rate, the 3D morphology and the corrosion resistance of the coating was studied by means of a glow discharge spectrometer, a shape-measuring laser microsystem, a Tafel curve and an electrochemical impedance spectrum. The results show that, according to the order of direct current, single pulse and reversing pulse, the content of nickel in the coating is reduced, the content of chromium and manganese is increased, the deposition rate is increased firstly, the surface roughness is reduced, and the corrosion resistance is enhanced. The surface of the plating layer prepared by the direct current mode has individual larger particles, the particle size of the surface of the plating layer prepared in the single pulse mode is relatively uniform, but there are still individual larger particles, and the plating layer prepared by the reversing pulse method is generally uniform and compact. The surface roughness of the coating prepared by the reversing pulse method is the lowest. In the 3.5% NaCl solution, the coating has the maximum corrosion potential (-0.305 V), the minimum corrosion current density (7.467-10 ~ (-8) A 路 cm ~ (-2)) and the maximum charge transfer resistance (5972惟路 cm ~ 2), and the corrosion resistance is the best.
【作者单位】：华北理工大学冶金与能源学院现代冶金技术教育部重点实验室;
【基金】：国家自然科学基金资助项目(51474088)
【分类号】：TQ153

【相似文献】