氧化参数对锆合金表面原位薄膜性能的影响规律

通过高温氧化工艺原位形成氧化锆膜技术是提高生物医学植入用锆合金材料使用性能的有效手段。采用扫描电子显电镜(SEM)、表面硬度测试、X射线衍射(XRD)及球盘式摩擦试验等方法研究了氧化温度及保温时间对氧化锆膜性能的影响规律。结果表明:氧化温度与保温时间增加,均会使氧化薄膜厚度增加,其中氧化温度对氧化薄膜厚度影响更大;氧化薄膜中t-ZrO_2体积分数是影响氧化薄膜表面硬度的重要因素,当氧化温度为500℃时,随着保温时间增加,氧化薄膜t-ZrO_2体积分数相应增加,其表面硬度增大;而当氧化温度为550℃时,氧化薄膜的t-ZrO_2体积分数和表面硬度均先增加后降低;获得氧化薄膜厚度、硬度与摩擦性能综合性能最优的参数为氧化温度550℃,保温时间6 h。

Effect of Oxidation Parameters on In-Situ Film Properties of Zirconium Alloys

The in-situ formation of zirconium oxide film by high temperature oxidation process is an effective method to improve the performance of zirconium alloy implants for biomedical implantation.The influence of oxidation temperature and holding time on the performance of zirconium oxide films was investigated by scanning electron microscopy(SEM),surface hardness testing,X-ray diffraction(XRD)and ball-disk friction tests.The results show that the increase of oxidation temperature and holding time will increase the thickness of the oxide film,and the oxidation temperature has a greater influence on the thickness of the oxide film.The volume fraction of t-ZrO 2 in the oxide film is an important factor affecting the surface hardness of the oxide film.When the oxidation temperature is 500°C,the volume fraction of oxide film t-ZrO 2 increases correspondingly with the increase of the heat preservation time,and its surface hardness increases.When the oxidation temperature is 550°C,both the volume fraction of t-ZrO 2 and the surface hardness of the oxide film increase first and then decrease.The optimal parameters for obtaining the comprehensive properties of oxide film thickness,hardness and wear resistance were oxidation temperature of 550°C and holding time of 6 h.