醇盐体系增材制造钛合金的电化学抛光机理

Electrochemical polishing characteristics of additively manufactured TC4 titanium alloy

电化学抛光是增材制造TC4钛合金表面处理的方法之一采用循环伏安、交流阻抗、计时电流及X射线光电子能谱仪(XPS)等测试方法,研究了乙二醇-氯化钠电解液中增材制造TC4钛合金的电化学抛光行为结果表明,钛合金在乙二醇-氯化钠体系中的氧化过程是Ti→TiO→Ti_(2)O_(3)→TiO_(2)施加不同的电位,影响钛合金表面氧化膜(也可称为钝化膜)厚度的演化,随着施加电位的增大,氧化膜厚度先增大后减小根据氧化膜厚度的变化规律提出两步抛光法,与单一钝化区电位抛光相比,两步抛光法抛光速率更大在25 min时钛合金表面取得了最佳抛光效果,此时粗糙度为26μm.

Electrochemical polishing is one of the surface treatment methods for TC4 titanium alloy additive manufacturingThe electrochemical polishing behavior of TC4 titanium alloy by additive manufacturing in ethylene glycol-sodium chloride electrolyte has been studied with testing methods such as cyclic voltammetry,AC impedance,chronoamperometry,and X-ray photoelectron spectroscopy(XPS)The results show that the oxidation order of titanium alloy in the ethylene glycol-sodium chloride system is Ti→TiO→Ti_(2)O_(3)→TiO_(2) The application potential affects the thickness process of the passive film on the titanium alloy surfaceWith the increase of the applied potential,the thickness of the passive film first increases and then decreasesAccording to the change law of the passivation film,a two-stage polishing method is proposed,in which the polishing rate is faster compared with the potential polishing of the single passivation zoneThe best polishing effect is achieved after 25 min of this method,and the surface roughness.