钛合金激光表面改性技术研究现状

钛合金密度小,比强度高,具有良好的耐蚀性、疲劳抗力,广泛应用于航空航天、国防、汽车、医疗等领域.然而,钛合金摩擦系数高、对粘着磨损和微动磨损非常敏感、耐磨性差及高温抗氧化性差等缺点,制约了它的应用.表面改性技术,尤其是激光表面改性技术为这一问题的解决提供了一条有效的途径,综述了国内外钛合金激光表面改性技术的研究现状,主要介绍了激光熔覆、激光合金化和激光熔凝技术及其在钛合金表面改性中的应用,并对其存在的主要问题及当前的研究热点:激光表面改性工艺参量优化、激光改性过程中裂纹产生机理及裂纹控制、复合激光表面改性技术、纳米改性层、功能梯度改性层、激光原位合成、激光熔覆非晶涂层、超短脉冲激光表面改性以及激光改性过程的数值模拟等进行了讨论.

Research States of Laser Surface Modification Technology on Titanium Alloys

Titanium alloys are used widely in aviation, national defense, automobile, medicine and other fields because of their advantages of lower density, excellent corrosion resistance, and good fatigue resistance et al. However, their high friction coefficient, high sensitivity to adhesive wear and fretting wear, as well as weak resistance to wear and bad resistance to high temperature oxidation restrict the application of titanium alloys. Surface modification technology, especially laser surface modification technology offers a way to solve these problems. The present situation of domestic and foreign research of laser surface modification technology on titanium alloys is reviewed, the laser cladding, laser alloying and laser melting and their applications are mainly introduced, and the main problems and research focus of laser surface modification technology on titanium alloys, such as optimization of processing parameters on laser surface modification, mechanism of crack forming and crack control during laser surface modification, composite laser surface modification technology, nanostructured coating, functionally gradient coating, laser in-situ synthesis, laser cladding amorphous coating, laser surface modification with ultrashort laser pulses and numerical simulation during laser surface modification are also discussed.