采用脉冲电镀法在Q235钢表面制备了Ni-Cr-Mo合金镀层,利用辉光放电光谱仪(GDS)、扫描电子显微镜(SEM)、Tafel曲线和电化学阻抗谱( EIS)考察了镀液温度对镀层元素含量、沉积速率、表面形貌和耐蚀性的影响。结果表明,随镀液温度的升高,镀层镍含量减小,铬含量先增大后减小,钼含量增大;镀层沉积速率稍有增大,镀层表面颗粒尺寸增大,镀层在3.5%NaCl溶液中耐蚀性先增强后减弱;镀液温度为30℃时,镀层最为均匀致密,且具有最大的自腐蚀电位(-0.535 V)、最小的腐蚀电流密度(0.123μA・cm-2)和最大的电荷转移电阻(2550Ω・cm2),耐蚀性最好。%Ni-Cr-Mo alloy coatings were prepared on the surface of Q 235 steel by pulse electroplating .The effect of bath temperature on coating element content , deposition rate , surface morphology and corrosion resistance were investigated by glow discharge spectroscopy (GDS), scanning electron microscopy (SEM), Tafel curve and electrochemical impedance spectroscopy ( EIS) .The results show that with increasing bath temperature , Ni content decreases , Cr content increases first and then decreases , Mo content increases; coating deposition rate increases slightly;the size of particles on coating surface increases;in 3.5%NaCl solution , corrosion resistance of coatings strengthens first and then weakens .Coating prepared at 30 ℃ is the most uniform and compact .And it with the biggest corrosion potential (-0.535 V) , the smallest corrosion current density (0.123μA・cm-2 ) and the biggest charge transfer resistance (2 550 Ω・cm2 ) exhibits the best corrosion resistance .
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