电化学抛光工艺参数对医用NiTi合金表面粗糙度的影响

Effects of electrochemical polishing on surface of NiTi alloy

为了获得优质表面质量的医用NiTi合金,探究了电流密度,抛光温度,极间距以及抛光时间对合金表面粗糙度的影响,试验结果表明,电流密度较小时试样表面残存较深的划痕,适当增大电流密度,表面粗糙度明显下降。电流密度过大时,发生过度腐蚀。随着抛光温度的升高,合金表面质量先降低后升高。极间距较小,使抛光液温度上升,出现过腐蚀坑,极间距离过大时,电流密度降低,抛光效果变差。抛光时间较短时,合金表面存在未完全抛光的划痕,当适当延长抛光时间,获得了光洁的表面,继续增加抛光时间合金表面出现过腐蚀坑,表面质量下降。

In order to obtain excellent surface quality NiTi alloy for medical use,the effects of current density,polishing temperature,electrode spacing,and polishing time on the surface roughness of the alloy were studied.The experiment results show that when the current density is small,there are still deep scratches on the surface of the sample;when the current density is appropriately increased,the surface roughness is obviously reduced,and when the current density is too large,excessive corrosion will occur.With the increase in polishing temperature,the surface quality of the alloy decreases at first and then increases.When the distance between electrodes is small,the temperature of the polishing solution will increase,and over-corrosion pits will appear.If the electrodes spacing is too large,the current density will be reduced and the polishing effect will be worse.When the polishing time is short,the surface of the alloy has scratches that are not polished completely.If the polishing time is prolonged properly,a smooth surface will be obtained.If the polishing time continues to be increased,over-corrosion pits will appear on the alloy surface,and the surface quality will decrease.