以亚微米级的粉末为原料制备Ti(C,N)基金属陶瓷,通过透射电镜(TEM)、扫描电镜(SEM)、能谱分析(EDX)等方法研究其在烧结过程中的组织结构变化规律及特点,并探讨烧结工艺参数对金属陶瓷力学性能的影响。结果表明,随着烧结温度升高,Ti(C,N)基金属陶瓷的组织更均匀,硬质颗粒逐渐球化,表面的Rim相更完整。Rim相分为两层,里层Rim相的Mo、W含量比外层Rim相高,里层Rim相是在固相烧结阶段形成的,外层Rim相是在液相烧结阶段形成的。Rim相的形成及晶粒长大都是通过溶解-析出机制进行的。在1 410℃下保温60 min,可获得较佳的力学性能,抗弯强度达2 266 MPa,硬度为HRA 90.6。
Ti(C,N)-based cermets were prepared with submicron powders. The microstructure evolution and characteristics during the sintering of the cermets were studied with TEM, SEM and EDX. Furthermore, the influence of main sintering technic parameters on the mechanical properties of Ti(C,N)-based cermets was also studied. With the sintering temperature rising, the microstructure becomes even gradually, and the ceramic grains and the rim get rounded. There exists the inner and outer rims between the hard cores and the binder. The inner rim, enriches Mo and W, is formed during solid phase sintering, and the outer rim is formed during liquid phase sintering by dissolution and precipitation. The cermets sintered at 1 410 ℃ for 60 rain exhibite the best mechanical properties Their transverse rupture strength reaches 2 266 MPa, and the hardness reaches 90.6 HRA