Titanium and titanium alloys have low density, good corrosion resistance, high specific strength and excellent biocompatibility, and are widely used in aerospace, biomedical implants and other fields. However, titanium and titanium alloys have the disadvantages of low surface hardness, especially poor wear resistance, which seriously limits their wider application. Therefore, surface modification is an important measure to improve the service performance of titanium alloy and further expand its application.
TA18 titanium alloy nominal composition is Ti-3Al-2.5V, is a near α type titanium alloy, the alloy has the advantage of room temperature and high temperature strength than pure titanium 20%~50%, welding performance and cold forming performance is better than common TC4 titanium alloy. Therefore, TA18 titanium alloy has been applied in the fields of military and civil aircraft parts and medical implants. In order to improve the service performance of TA18 titanium alloy, surface modification is necessary.
Surface oxidation treatment is a relatively simple surface modification method. After oxygen diffusion treatment, titanium alloys can not only form a thin, high-corrosion resistant oxide film on the surface, but also form susaturated solid solution in the Ti matrix, thereby increasing the surface hardness [4-5]. The common chemical oxidation, electrochemical oxidation and micro-arc oxidation have complicated processes and substandard environmental protection, which restricts the promotion and application of these oxidation technologies [6-8]. Thermal oxidation is a treatment method in which titanium and titanium alloys are heated to a certain temperature in a resistance furnace in an atmospheric environment and held for a period of time to form a dense oxide film on the surface, thereby improving the surface properties of titanium and titanium alloys. You can see,
The thermal oxidation method has the obvious advantages of simple and convenient process, no pollution and low cost [9-11]. However, the selection of thermal oxidation process is very important, and when the process selection is unreasonable, not only can not achieve the effect of improving the performance of titanium alloy, but also may have negative effects. In this study, the surface modification of TA18 titanium alloy was carried out by thermal oxidation method. Considering the influence of thermal oxidation time on the modification effect and process efficiency, the thermal oxidation time of the system was selected as 210 min to explore the influence of thermal oxidation temperature on the surface modification effect of TA18 titanium alloy. The aim is to obtain the thermal oxidation temperature to improve the surface hardness, friction and wear property and corrosion resistance, so as to provide guidance for the selection of thermal oxidation process conditions in the practical application of TA18 titanium alloy, and achieve the beneficial effect of further expanding the application range of titanium alloy.
