热氧化提高钛及钛合金表面性能的研究进展

Research Progress of Thermal Oxidation Effect on Improving Surface Properties of Titanium and Titanium Alloy

热氧化作为一种引起广泛关注的钛及钛合金表面改性技术,具有工艺简单、原位生长、薄膜厚度大以及性价比高等特点。通过热氧化表面处理技术能够在钛及钛合金表面形成较厚的由钛氧化层和氧的扩散层组成的硬质氧化膜,氧化膜对材料起到有效的保护作用,提高了材料单一耐磨性、耐蚀性以及生物活性或综合表面性能。从热氧化工艺原理及其对钛及钛合金表面性能影响的角度,综述了热氧化对钛及钛合金表面硬度、耐磨性、耐蚀性、生物相容性等性能影响的研究进展,并对其以后的研究方向进行了展望。通过合理控制氧化温度、氧化时间、氧化气氛及冷却方式等工艺条件,从而得到连续、致密且疲劳性能较好的金红石型TiO_2和氧的扩散层是改善钛及钛合金性能的关键。将热氧化处理与其他工艺相结合,针对性地提高膜层厚度及材料的耐磨性、耐蚀性、生物性能等,以实现复合涂层的制备将是热氧化在钛及钛合金性能改善方面的研究方向。

As a surface modification technology of titanium and titanium alloys having aroused wide concern, thermal oxidation features in simple process, in situ growth, thick oxide coating and high cost performance. Thick hard oxide film consisting of Ti oxide layer and oxygen diffusion layer was formed on the surface of Ti and Ti alloys by virtue of thermal oxidation surface treatment technology. The oxide film could protect materials effectively and also improve single wear resistance, corrosion resistance and biological activity or comprehensive surface properties significantly. Research progress regarding effects of thermal oxidation on properties of Ti and Ti alloys （surface hardness, wear resistance, corrosion resistance, biological biocompatibility, etc.） was summarized from the perspective of thermal oxidation process principle and its effect on surface properties of Ti and Ti alloys. In addition, the research trend was expected. Continuous and compact hard oxide layer consisting of rutile and oxygen diffusion layer of good fatigue performance was obtained by controlling such process conditions as oxidation temperature, oxidation time, oxidation atmosphere and cooling mode properly. Such an oxide layer was the key to improve properties of Ti and Ti alloys. The research direction of thermal oxidation in improving properties of Ti and Ti alloys is preparing composite coatings by combining thermal oxidation with other processes and being targeted to improve film thickness as well as wear resistance, corrosion resistance and biological properties of materials.