TC4钛合金表面CrAlN涂层的制备及性能研究

Research on Preparation and Performance of CrAlN Coating on TC4 Titanium Alloy Surface

为提高TC4(Ti-6Al-4V)钛合金的表面硬度和耐磨性能,利用等离子氮化技术将TC4钛合金进行氮化处理,然后利用多弧离子镀技术在氮化层上制备了CrAlN涂层。分析了所制备涂层的表面相结构、显微形貌、显微硬度和摩擦磨损性能。结果表明:TC4钛合金表面经氮化处理后表面硬度明显提高,耐磨性也得到明显改善;在氮化层上制备的CrAlN涂层,其相结构主要是面心立方结构的Cr N相,表面硬度达到了2145 HV;TC4钛合金基体其磨损机制主要是磨粒磨损和粘着磨损,氮化层的磨损机制主要是磨粒磨损和轻微的粘着磨损,而CrAlN涂层的磨损机制以粘着磨损为主,磨损程度依次为:TC4钛合金基体>氮化层>CrAlN涂层。使用高温乙炔枪灼烧之后,发现在氮化层上制备的CrAlN涂层无脱落现象,且表面显微硬度达2494 HV。

In order to improve the surface hardness and wear resistance of TC4(Ti-6Al-4V) titanium alloy, the TC4 titanium alloy was first nitrided by using plasma nitriding technology, and then CrAlN was prepared on the nitrided layer using multi-arc ion plating technology coating. The phase structure, surface micromorphology, surface microhardness and friction and wear performance of the prepared coating were analyzed. The results show that the surface hardness of the TC4 titanium alloy surface after nitriding treatment significantly improves, and the wear resistance also significantly improves;the phase structure of CrAlN coating prepared on the nitride layer is mainly the face-centered cubic structure Cr N phase, and the surface hardness reaches 2145 HV;the wear mechanism of the TC4 titanium alloy matrix is mainly abrasive wear and adhesion wear,and the wear mechanism of the nitride layer is mainly abrasive wear and slight adhesive wear, and the wear mechanism of CrAlN coating is mainly adhesive wear, and the degree of wear is: TC4 titanium alloy substrate>nitride layer>CrAlN coating;after burning with a high temperature acetylene gun, the CrAlN coating prepared on the nitrided layer has no shedding phenomenon, and the surface hardness reaches 2494 HV.