正向电压对TC4钛合金微弧氧化膜层性能的影响

Effect of Forward Voltage on Coating Performance of TC4 Alloy with Micro-arc Oxidation

在磷酸二氢钠、乙酸钙及EDTA混合电解液中,对TC4钛合金表面采用微弧氧化技术制备陶瓷膜层。使用膜层测厚仪和粗糙度仪对膜层进行检测,同时用SEM、EDS及XRD对膜层的表面形貌、化学成分及相组成进行分析。结果表明:随正向电压的逐渐升高,陶瓷层厚度呈上升趋势;微孔孔径逐渐增大,数量减少,粗糙度也不断增大;P、Ca二种元素的含量随正向电压升高逐渐增大,不稳定的锐钛矿型TiO2逐渐向稳定的金红石型TiO2变化。

Ceramic coating was fabricated on the surface of Ti6Al4 V alloy by micro-arc oxidation（MAO） method in Ca（CH3COO）2·H2O-NaH2PO4-EDTA solution, and was tested using the film thickness gauge and roughness gauge. The surface morphology, chemical composition, phase composition of micro-arc oxidation film layer were analyzed by SEM, EDS and XRD. The results show that, with the increase of forward voltage, the thickness and roughness of coating increase, the diameters of holes on surface of the ceramic coating increase, but the numbers of holes decrease. With the increase of forward voltage, the content of P, Ca elements increases, unstable anatase TiO2 gradually changes to stable rutile TiO2.