Li Juncai, Chen Ying, Guan Chuang, Zhang Chao, Zhao Ji, Yu Tianbiao
School of Mechanical Engineering and Automation, Northeastern University, Shenyang 110819, China.
Materials (Basel). 2024 Aug 5;17(15):3878. doi: 10.3390/ma17153878.
In recent years, laser cladding technology has been widely used in surface modification of titanium alloys. To improve the wear resistance of titanium alloys, ceramic-reinforced nickel-based composite coatings were prepared on a TC4 alloy substrateusing coaxial powder feeding laser cladding technology. Ti (C, N) ceramic was synthesized in situ by laser cladding by adding different contents (10%, 20%, 30%, and 40%) of TiN, pure Ti powder, graphite, and In625 powder. Thisestudy showed that small TiN particles were decomposed and directly formed the Ti (C, N) phase, while large TiN particles were not completely decomposed. The in situ synthetic TiCN phase was formed around the large TiN particles. With the increase in the proportion of powder addition, the wear volume of the coating shows a decreasing trend, and the wear resistance of the surface coating is improving. The friction coefficient of the sample with 40% TiN, pure Ti powder, and graphite powder is 0.829 times that of the substrate. The wear volume is 0.145 times that of the substrate. The reason for this is that with the increase in TiN, Ti, and graphite in the powder, there are more ceramic phases in the cladding layer, and the hard phases such as TiC, Ti(C, N) and Ti2Ni play the role in the structure of the "backbone", inhibit the damage caused by micro-cutting, and impede the movement of the tearing point of incision, so that the coating has a higher abrasion resistance.
近年来，激光熔覆技术已广泛应用于钛合金的表面改性。为提高钛合金的耐磨性，采用同轴送粉激光熔覆技术在TC4合金基体上制备了陶瓷增强镍基复合涂层。通过添加不同含量（10%、20%、30%和40%）的TiN、纯Ti粉、石墨和In625粉，利用激光熔覆原位合成Ti（C，N）陶瓷。本研究表明，细小的TiN颗粒分解并直接形成Ti（C，N）相，而粗大的TiN颗粒未完全分解，粗大TiN颗粒周围形成原位合成的TiCN相。随着添加粉末比例的增加，涂层的磨损体积呈下降趋势，表面涂层的耐磨性提高。添加40%TiN、纯Ti粉和石墨粉的试样摩擦系数为基体的0.829倍，磨损体积为基体的0.145倍。其原因是随着粉末中TiN、Ti和石墨的增加，熔覆层中陶瓷相增多，TiC、Ti（C，N）和Ti2Ni等硬质相在组织中起到“骨架”作用，抑制微切削造成的损伤，阻碍切口撕裂点的移动，使涂层具有较高的耐磨性能。
