Nb_(2)O_(5)/TiO_(2)微弧氧化复合膜层微观组织和高温性能  

Microstructure and High Temperature Properties of Nb_(2)O_(5)/TiO_(2) Coatings by Micro-arc Oxidation

作　　者：郭豫鹏 蔚振国 丁祺文 陆晓峰[1] 朱晓磊[1] Guo Yupeng;Wei Zhenguo;Ding Qiwen;Lu Xiaofeng;Zhu Xiaolei(School of Mechanical and Power Engineering,Nanjing Tech University,Nanjing 211816,China)

机构地区：[1]南京工业大学机械与动力工程学院,江苏南京211816

出　　处：《稀有金属材料与工程》2023年第5期1835-1841,共7页Rare Metal Materials and Engineering

基　　金：国家自然科学基金面上项目(11772147)。

摘　　要：为了研究Ti6Al4V钛合金微弧氧化膜层的抗高温氧化性能,在硅酸钠电解液中添加纳米铌(Nb)颗粒制备了Nb_(2)O_(5)/TiO_(2)复合膜层。采用扫描电子显微镜(SEM)和X射线衍射仪(XRD)分析膜层的微观结构和相组成。结果表明:随着纳米Nb浓度增加,膜层表面微孔直径增大、数量减小,膜层中Nb元素含量逐渐增加至5at%,膜层厚度由42.28μm增加至55.48μm;膜层由锐钛矿型TiO_(2)、金红石型TiO_(2)、Al2TiO_(5)、Nb_(2)O_(5)及Nb-Ti化合物组成,金红石型TiO_(2)峰值和Nb_(2)O_(5)峰值逐渐上升;试样增重由基体10.25 mg/cm^(2)降低至Nb浓度为6 g/L制备膜层的2.281 mg/cm^(2),平均氧化速率由2.8472×10^(-5)mg·cm^(-2)·s^(-1)降低至6.3361×10^(-6)mg·cm^(-2)·s^(-1);膜层裂纹随Nb浓度增加而减少,有效改善了膜层的抗高温氧化性能。To study the high temperature oxidation resistance of micro-arc oxidation coatings of Ti6Al4V titanium alloy,Nb_(2)O_(5)/TiO_(2) composite coatings were prepared by adding nano-Nb particles into sodium silicate electrolyte.The microstructure and phase composition of the coatings were analyzed by scanning electron microscopy(SEM)and X-ray diffractometry(XRD).The results show that with the increase in nano-Nb concentration,the micropores on the surface of the coatings increase in diameter and decrease in number.The content of Nb increases to 5at%,the thickness of the coatings increases from 42.28μm to 55.48μm.The coatings are composed of anatase TiO_(2),rutile TiO_(2),Al2TiO_(5),Nb_(2)O_(5) and Nb-Ti compounds while the peak value of rutile TiO_(2) and Nb_(2)O_(5) gradually increase.The mass gain of the sample decreases from 10.25 mg/cm^(2) to 2.281 mg/cm^(2) of the coatings with 6 g/L Nb concentration,the average oxidation rate decreases from 2.8472×10^(-5) mg·cm^(-2)·s^(-1) to 6.3361×10^(-6) mg·cm^(-2)·s^(-1).The crack number of the coatings decrease with increasing the Nb concentration,which effectively improve the high temperature oxidation resistance of the coatings.

关 键 词：微弧氧化 纳米铌 微观组织 高温抗氧化性能 

分 类 号：TG174.4[金属学及工艺—金属表面处理]