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采用脉冲电沉积法在Q235钢表面制备Ni-Sn-Mn合金镀层.利用辉光放电光谱仪(GDS)、扫描电镜(SEM)、Tafel曲线和电化学阻抗谱(EIS)考察了镀液pH对镀层元素质量分数、沉积速率、表面形貌、阴极电流效率和耐蚀性的影响.结果表明,随着pH的增大,镀层Sn和Ni质量分数减小,Mn的质量分数增大;镀层沉积速率先增大后减小;阴极电流效率先提高后降低;镀层在3.5％ NaCl溶液中耐蚀性先增强后减弱.当pH为4.0时,所得镀层均匀致密,自腐蚀电位(-0.395 V)最正,自腐蚀电流密度(2.594× 10-8 A/cm2)最小,电荷转移电阻值(6 945 Ω·cm2)最大,耐蚀性最好.“,”Ni-Sn-Mn alloy coating is prepared on the surface of Q235 steel via the pulse electrodeposition method.The effects of pH value of electroplating solution on the mass content of coating elements,deposition rate,surface morphology,cathode current efficiency and corrosion resistance are investigated by glow discharge spectroscopy (GDS),scanning electron microscopy (SEM),Tafel curve and electrochemical impedance spectroscopy (EIS).The results show that with the increasing pH value of electroplating solution,the contents of both Sn and Ni in coating decrease but the content of Mn increases.With the increasing pH,the deposition rate of coating and the cathode current efficiency both are increasing firstly and then dropping,and the corrosion resistance of coating is firstly augmenting and then weakening in a 3.5％ NaC1 solution.The coating prepared in the bath with a pH value of 4.0 is uniform and compact,and has the biggest corrosion potential (-0.395 V),the smallest corrosion current density (2.594× 10-8 A· cm-2) and the biggest charge transfer resistance (6 945 Ω· cm2),and exhibits the best corrosion resistance.