脉冲电镀Ni-Cr-Mo合金镀层施镀时间的研究
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摘要
采用脉冲电镀法在Q235钢表面制备Ni-Cr-Mo合金镀层。利用扫描电镜(SEM)、辉光放电光谱仪(GDS)、Tafel曲线和电化学阻抗谱(EIS)考察了施镀时间对镀层表面形貌、形成过程、镀层厚度、元素含量和耐蚀性的影响。结果表明:镀层由粒状结构形核、长大并逐层叠加形成;镀层的形成存在一个孕育期,孕育期后一定时间内镀层增厚较为困难,施镀时间继续增大,镀层可顺利增厚。随施镀时间的增大,镀层镍含量增大,铬含量减小,钼含量减小。在3.5%NaCl溶液中,镀层耐蚀性先增强后减弱。施镀时间为50 min时制备的镀层具有最大的自腐蚀电位(-0.355 V)、最小的腐蚀电流密度(0.006μA·cm~(-2))和最大的电荷转移电阻(26544Ω·cm~2),耐蚀性最好。
Ni-Cr-Mo alloy coatings were prepared on the surface of Q235 steel by pulse electroplating method. The effects of electroplating time on surface morphology, forming process, thickness, element content and corrosion resistance of the coating were investigated by scanning electron microscopy(SEM), glow discharge spectroscopy(GDS), Tafel curve and electrochemical impedance spectroscopy(EIS). The results show that the coating forms from the particles structure nucleating,growing and stacking from each layer. In the form of the coating, an incubation period exists. The coating is hard to become thickness for a certain time after incubation period. After this, with the electroplating time increasing, the coating is easy to become thick. With electroplating time increasing, Ni content in the coating increases, Cr content decreases and Mo content decreases. In 3.5% Na Cl solution, the corrosion resistance of the coatings strengthens firstly and then weakens. The coating prepared by electroplating for 50 min has the biggest self corrosion potential(-0.355 V), the smallest corrosion current density(0.006 μA·cm~(-2)) and the biggest charge transfer resistance(26544 Ω·cm~2), which exhibits the best corrosion resistance.
Ni-Cr-Mo alloy coatings were prepared on the surface of Q235 steel by pulse electroplating method. The effects of electroplating time on surface morphology, forming process, thickness, element content and corrosion resistance of the coating were investigated by scanning electron microscopy(SEM), glow discharge spectroscopy(GDS), Tafel curve and electrochemical impedance spectroscopy(EIS). The results show that the coating forms from the particles structure nucleating,growing and stacking from each layer. In the form of the coating, an incubation period exists. The coating is hard to become thickness for a certain time after incubation period. After this, with the electroplating time increasing, the coating is easy to become thick. With electroplating time increasing, Ni content in the coating increases, Cr content decreases and Mo content decreases. In 3.5% Na Cl solution, the corrosion resistance of the coatings strengthens firstly and then weakens. The coating prepared by electroplating for 50 min has the biggest self corrosion potential(-0.355 V), the smallest corrosion current density(0.006 μA·cm~(-2)) and the biggest charge transfer resistance(26544 Ω·cm~2), which exhibits the best corrosion resistance.
引文
[1]王心悦,杨海丽,刘海鹏,等.p H对脉冲电镀锌-镍-锰合金的影响[J].电镀与涂饰,2016,35(9):449-453.
[2]Xin M,Jie W,Dong J H,et al.In-situ corrosion monitoring of mild steel in a simulated tidal zone without marine fouling attachment by electrochemical impedance spectroscopy[J].J.Mater.Sci.Technol.,2014,30(10):1043-1050.
[3]Qian Bei,Hou Baorong,Zheng Meng.The inhibition effect of tannic acid on mild steel corrosion in seawater wet/dry cyclic conditions[J].Corrosion Science,2013,72:1-9.
[4]Wang Qinying,Bai Shulin,Zhang Yangfei et al.Improvement of Ni-Cr-Mo coating performance by laser cladding combined re-melting[J].Applied Surface Science,2014,308:285-292.
[5]Wang Qinying,Wang Xianzong,Luo H,et al.A study on corrosion behaviors of Ni-Cr-Mo laser coating,316 stainless steel and X70 steel in simulated solutions with H2S and CO2[J].Surface&Coatings Technology,2016,291:250-257.
[6]Higuera Hidalgo V,Belzunce Varela F J,Fernández Rico E.Erosion wear and mechanical properties of plasma-sprayed nickel-and iron-based coatings subjected to service conditions in boilers[J]Tribology International,1997,30(9):641-649.
[7]程付鹏,曹志颖,文钟晟,等.AISI 430不锈钢表面Co-Ni合金脉冲电沉积的过程[J].材料保护,2015,48(7):11-14.
[8]曾跃,姚素薇,郭鹤桐.从氨性柠檬酸溶液中电沉积Ni-Mo的机理研究[J].物理化学学报,1995,11(4):351-355.
[9]左晓婷,姚萍屏,贡太敏,等.WC粒度对超音速火焰喷涂WC-10Co-4Cr涂层耐腐蚀性能的影响[J].粉末冶金材料科学与工程,2015,20(1):106-111.
[10]王心悦,杨海丽,刘海鹏,等.p H对脉冲电镀锌-镍-锰合金的影响[J].电镀与涂饰,2016,35(9):449-453.
[11]张鉴清.电化学测试技术[M].北京:化学工业出版社,2010:164.
[2]Xin M,Jie W,Dong J H,et al.In-situ corrosion monitoring of mild steel in a simulated tidal zone without marine fouling attachment by electrochemical impedance spectroscopy[J].J.Mater.Sci.Technol.,2014,30(10):1043-1050.
[3]Qian Bei,Hou Baorong,Zheng Meng.The inhibition effect of tannic acid on mild steel corrosion in seawater wet/dry cyclic conditions[J].Corrosion Science,2013,72:1-9.
[4]Wang Qinying,Bai Shulin,Zhang Yangfei et al.Improvement of Ni-Cr-Mo coating performance by laser cladding combined re-melting[J].Applied Surface Science,2014,308:285-292.
[5]Wang Qinying,Wang Xianzong,Luo H,et al.A study on corrosion behaviors of Ni-Cr-Mo laser coating,316 stainless steel and X70 steel in simulated solutions with H2S and CO2[J].Surface&Coatings Technology,2016,291:250-257.
[6]Higuera Hidalgo V,Belzunce Varela F J,Fernández Rico E.Erosion wear and mechanical properties of plasma-sprayed nickel-and iron-based coatings subjected to service conditions in boilers[J]Tribology International,1997,30(9):641-649.
[7]程付鹏,曹志颖,文钟晟,等.AISI 430不锈钢表面Co-Ni合金脉冲电沉积的过程[J].材料保护,2015,48(7):11-14.
[8]曾跃,姚素薇,郭鹤桐.从氨性柠檬酸溶液中电沉积Ni-Mo的机理研究[J].物理化学学报,1995,11(4):351-355.
[9]左晓婷,姚萍屏,贡太敏,等.WC粒度对超音速火焰喷涂WC-10Co-4Cr涂层耐腐蚀性能的影响[J].粉末冶金材料科学与工程,2015,20(1):106-111.
[10]王心悦,杨海丽,刘海鹏,等.p H对脉冲电镀锌-镍-锰合金的影响[J].电镀与涂饰,2016,35(9):449-453.
[11]张鉴清.电化学测试技术[M].北京:化学工业出版社,2010:164.