TB8钛合金间歇式真空气体渗氮层的组织与性能

Microstructure and property of intermittent vacuum gas nitriding layer on TB8 titanium alloy

摘要:

为了提高表面硬度和耐磨性,对TB8钛合金进行间歇式真空气体渗氮处理。利用XRD和SEM分析了改性层的物相组成和显微组织,并对改性层的表面硬度和耐磨性进行了研究。结果表明,TB8钛合金经800 ℃间歇式真空气体渗氮4 h后,表面改性层物相主要由TiN、TiN0.3、Ti2AlN、及α-Ti组成,渗氮层组织致密,与基体结合良好,表面硬度为900-950HV,比基体硬度提高了近3倍,硬化层厚度为80-100 μm,由于表面形成了梯度硬化层,耐磨性得到了极大改善。

Abstract:

The intermittent vacuum gas nitriding (IVGN) process was introduced to improve the surface properties of TB8 titanium alloys. The phase constitution and microstructure of the surface-modified layer were measured by XRD and SEM, and the surface hardness and wear resistance of the treated samples were analyzed. The results indicated that a surface-modified layer composed of TiN, TiN_0.3, and Ti₂AlN was formed after IVPN treatment at 800 ℃ for 4 h. The microstructure of modified layer was dense and had a good bonding with its substrate. The surface hardness of treated samples was up to 850-900 HV, which was three times as much as that of the untreated samples. The thickness of hardened layer was about 80-100μm. The wear resistance was greatly improved due to the formation of a gradient hardened layer.