周期反向脉冲对镀铁性能的影响

Influence of Periodic Reverse Pulse Current on the Performance of Steeling Coating

直流镀铁修复零件,其镀层脆性大,达不到原件的机械强度,而且易生锈,不能用于装饰镀,周期反向脉冲镀铁可以克服以上缺点。在保持正、负脉冲时间之比相等的条件下,研究了增加正脉冲持续时间对镀铁的覆盖能力、表面形貌、镀层和基体的结合力、电沉积效率和镀层的显微硬度等性能的影响。结果表明在相同的电流密度下,周期反向脉冲镀铁层可深入铜圈1·6cm,镀层强度达38kN,硬度高,韧性好、伸长率达3%;电流效率高,电沉积效率达86%,深镀能力强。

Direct current steeling used for repair of metallic parts has the disadvantages of high coating brittleness and low mechanical strength,and the resulting coating is liable to rust and unsuitable to decoration plaiting.It could be feasible to get rid of those disadvantages by introducing periodic reverse pulse current in the steeling process.Thus the influence of increased positive pulse duration on the surface appearance,covering capacity,adherence,depositing efficiency,hardness,and other performances of the steeling coating was investigated on condition of keeping the positive/negative duration ratio constant.As the results,it was feasible to significantly increase the strength,hardness,and toughness of the steeling coating by applying periodic reverse pulse current,and the electroplating efficiency and covering power was also increased as compared with the direct current eletroplating at the same electric current density.