钛及其合金因具有较好的耐蚀抗磨性、生物活性、生物相容性以及在生理环境中的无毒性，成为医用领域中最常用的一种金属材料。但是，钛及其合金自身无抗菌性，表面摩擦因数大，抗塑性剪切能力低，且长期服役中易被环境污染和易于磨损失效，这些特性在一定程度上限制了其应用领域的扩展。因而，学者常采用离子注入技术对医用钛及其合金进行表面改性，以提升其表面性能，延长其制件服役寿命和扩展材料应用范围。研究表明，单一元素离子注入对提升钛及其合金的医用性能不够理想，因而学者采用金属+非金属、金属+金属离子进行复合注入，旨在提升改性层减摩抗磨、耐蚀性能的同时，增强改性层的生物活性及服役过程中的抗菌性。另外，对现有研究展开分析与综述后，提出了对医用钛及其合金的离子注入改性，将朝着进一步深入理论、模拟研究，多复合离子（特别是金属+金属+非金属复合离子）注入研究，高性能离子注入设备研发及其离子注入参数拟定与优化等方面发展。

Titanium and its alloys have become the most commonly used metal materials in the medical field due to their good corrosion resistance, biological activity, biocompatibility and non-toxicity in physiological environments. However, titanium and its alloys are easily polluted by environment and wore out during long-term service due to lack of antibacterial properties, high friction factor and low resistance to plastic shear, which limits the expansion of their application to a certain extent. Therefore, some scholars often apply ion implantation technology to modify the surface of titanium and its alloys in order to improve the surface performance and extend the service life of their parts and expand their application range. Studies have shown that a single element ion implantation is insufficient to improve the medical performance of titanium and its alloys, so some scholars use multiple implantation technology with metal + non-metal or metal + metal ions, aiming to improve the anti-friction and anti-wear properties, and the corrosion resistance of the modified layer, as well as enhance the biological activity and the antibacterial properties during service. In addition, after the existing researches were analyzed and reviewed, the development trend on medical titanium and its alloys modified by ion implantation was proposed for further in-depth theoretical and simulation research, multiple ions (especially metal + metal + non-metal multiple ions) implantation research, the development of a high-performance ion implantation equipment and formulation and optimization of its ion implantation parameters.