The quality of titanium coating mainly depends on its morphology and compactness. Generally, the titanium coating prepared by galvanostatic electroplating has poor quality due to the formation of dendrite. The electrochemical behavior of Ti2+ at cathode was studied in a NaCl-KCl-TiCl2 melt containing 5.4wt％ Ti2+ by cyclic voltammetry and reversal chronopotentiometry. The results showed that the cathodic reduction of titanium is a one-step diffusioncontrolled reaction. To avoid dendrite, pulse current method was used for electrodeposition of titanium on stainless steel substrate from the said melt. A compact titanium coating with large grains and a current efficiency of nearly 90％ can be obtained at a current density of 0.3 A/cm2 when T = 10 s and ton: toff = 5: 5.%钛镀层的质量主要取决于其形貌和致密度.采用恒电流电镀得到的钛镀层极易产生枝晶,因而质量较差.本文采用循环伏安法和换向计时电位法,在含5.4%(质量分数)Ti2+的NaCl-KCl-TiCl2熔盐中研究了Ti2+的阴极电化学行为.结果表明,钛的阴极还原是一个一步反应,且主要受扩散控制.为避免枝晶,在上述熔盐体系中,以不锈钢为阴极,采用脉冲电流法进行镀钛.当周期为10S,通断比为5:5时,在电流密度为0.3 A/cm2的条件下,可以制备出颗粒尺寸大且致密的钛镀层,其电流效率接近90%.
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