Er(NO3)3掺杂对TC4微弧氧化涂层电化学行为的影响

Influence of Er(NO3)3 Doping on Electrochemical Behavior of TC4 MAO Coating

针对TC4合金耐腐蚀性偏低的问题,利用微弧氧化技术在TC4表面制备陶瓷涂层,探究了电解液中Er(NO3)3掺杂量对TC4微弧氧化(MAO)涂层润湿性能和电化学行为的影响作用。结果表明:随着Er(NO3)3含量的增加,TC4涂层中金红石相TiO2衍射峰逐渐加强,锐钛矿相TiO2减弱。在电解液中引入适量Er(NO3)3有助于促进金红石相TiO2形成。Er(NO3)3含量变化对TC4钛合金微弧氧化涂层表面粗糙度的影响不大,粗糙度在6~12μm内。在电解液中引入Er(NO3)3后,TC4涂层的极化曲线会向正电位方向移动。增加Er(NO3)3含量,腐蚀电位增加。

In view of the poor corrosion resistance of TC4 alloy,the micro-arc oxidation technology was used to fabricate ceramic coating on the surface of TC4,then the relationship between Er(NO3)3 doping amount in micro-arc oxidation electrolyte and the wettability performance of TC4 micro-arc oxidation coating was investigated.The results show that as the content of Er(NO3)3 increases,the diffraction peak of rutile phase TiO2 in TC4 coating reinforces gradually,while that of anatase phase TiO2 weakens.The introduction of Er(NO3)3 into the electrolyte can promote the formation of rutile TiO2.The change of Er(NO3)3 content has little effect on the surface roughness of TC4 micro-arc oxidation coating,which is within the range of 6-12μm.After the introduction of Er(NO3)3 into the electrolyte,the polarization curve of the TC4 micro-arc oxidation coating moves into the direction of positive potential.With the increase of Er(NO3)3 content,the corrosion potential increases.