The effects of milling time on the particle size distribution (PSD), densification, microstructure, hardness and fracture toughness of spark plasma sintered (SPS) TiN+graphite ceramic were studied. TiN with varying amount of graphite (1, 3, and 5 wt%) were milled at different milling time (8, 24 and 40 h), thereafter sintered at sintering temperature of 1800 °C, holding time of 10 min and pressure of 50 MPa. The relative density and hardness increased as milling time progressed from 24 to 40 h, however, the relative density, hardness, and particle size decreased after 8 h of milling. The microstructural analyses showed that a fully sintered TiN+graphite compact could be achieved at sintering temperature of 1800 °C, with no significant grain growth. Residual stress effect of TiN+5 wt% graphite composite was analyzed using XRD method and the result indicated that there is no significant residual stress on the sample. The relative density, Vickers hardness and fracture toughness of TiN+ 1 wt% Gr, milled for 40 h were 99.24%, 13.90 GPa and 4.0 MPa.m^1/2 respectively.

研究了铣削时间对火花等离子体烧结（SPS）TiN +石墨陶瓷的粒度分布（PSD），致密化，显微组织，硬度和断裂韧性的影响。在不同的研磨时间（8、24和40 h）下研磨具有不同含量的石墨（1、3和5 wt％）的TiN，然后在1800°C的烧结温度，10分钟的保持时间和50的压力下烧结MPa。随着研磨时间从24小时增加到40小时，相对密度和硬度增加，但是，研磨8小时后，相对密度，硬度和粒度降低。显微组织分析表明，在1800°C的烧结温度下可以获得完全烧结的TiN +石墨压块，而没有明显的晶粒长大。用XRD分析了TiN + 5 wt％石墨复合材料的残余应力效应，结果表明样品上没有明显的残余应力。研磨40 h的TiN + 1 wt％Gr的相对密度，维氏硬度和断裂韧性分别为99.24％，13.90 GPa和4.0 MPa.m^1/2。