Na_2SiO_3系溶液中Ti6Al4V微弧氧化陶瓷膜的结构与力学性能

Microstructure and Mechanical Properties of Ceramic Coatings Produced on Ti6Al4V by Micro-arc Oxidation in Na_2SiO_3 Solution

采用交流微弧氧化法于Na2SiO3-KOH-(NaPO3)6-NaAlO2溶液中在Ti6Al4V表面形成了氧化物陶瓷膜。用扫描电镜和X射线衍射研究了陶瓷膜的组织形貌和相组成,用Nano IndenterXP系统研究膜层的力学特性。结果表明:氧化膜分为3层,即过渡层、致密层与疏松层。膜层主要由金红石相TiO2及少量锐钛矿相TiO2组成。膜层中致密层与基底的弹性回复分别为40.5%和14.9%,硬度分别为8.54 GPa和5.5 GPa,弹性模量分别为87.4 GPa和150 GPa,膜层表现出明显的陶瓷特征。

Ceramic oxide coatings were fabricated on a Ti6Al4V alloy surface by micro-arc oxidation (MAO) in Na2SiO3-KOH-(NaPO3)6-NaAlO2 solution using an AC power supply. Microstructure, phase and composition of ceramic coatings were characterized by SEM and XRD respectively. Mechanical properties were studied using a Nano Indenter XP system. The results show that ceramic coatings possess three layers transitional, dense and loose layer, composed mainly of rutile TiO2 and a small amount of anatase TiO2. Elastic recovery is 40.5% and 14.9%, hardness is 8.54 GPa and 5.5 GPa, and elastic modulus is 87.4 GPa and 150 GPa in the dense layer and the substrate, respectively, The MAO coating indicates pronounced ceramic characteristics.