电流密度和抛光时间对镍钛合金管电解抛光的影响

Effects of current density and treatment time on electropolishing of Ni-Ti alloy tube

采用高氯酸−冰醋酸体系对镍钛合金管电解抛光。在温度25 ℃及抛光间隙15 mm的条件下研究了抛光时间(60~120 s)和电流密度(0.75~1.75 A/cm^(2))对抛光效果的影响。结果表明,随着抛光时间延长或电流密度增大,钛合金管的表面粗糙度先减小后增大,残余压应力先增大后减小,较佳的电流密度和抛光时间分别为1.15 A/cm^(2)和90 s。在该条件下电解抛光后,镍钛合金管表面平整光亮,凹坑最少,表面粗糙度最小(为53.8 nm),表面残余压应力最大(为175.8 MPa)。

The electropolishing of Ni–Ti alloy tube was conducted in an electrolyte primarily composed of perchloric acid and glacial acetic acid.The effects of polishing time(60-120 s)and current density(0.75-1.75 A/cm^(2))on the polishing effectiveness were studied at temperature 25 ℃ and interelectrode distance 15 mm.The results showed that the surface roughness of Ni–Ti alloy tube was decreased initially and then increased with the increasing of polishing time or current density,while the residual compressive stress was changed conversely.The optimal current density and polishing time were 1.15 A/cm^(2) and 90 s,respectively.After being electropolished under the optimized conditions,the Ni–Ti alloy tube was smooth and bright with the least amount of pits,the minimum roughness of 53.8 nm,and the maximum residual compressive stress of 175.8 MPa.