【摘要】 采用粉末冶金真空烧结方法制备了Ti(C,N)/NiCr金属陶瓷.研究了TiN含量对Ti(C,N)/NiCr金属陶瓷微观结构与力学性能的影响.结果表明,TiN的加入既改变了金属陶瓷硬质相颗粒的尺寸.使其变小,也改变了硬质相颗粒的形貌, 使其由圆形变为多边形;随TiN含量的增加,金属陶瓷的抗弯强度均出现先增加后降低的规律,但在较低的烧结温度下,抗弯强度在TiN含量为4%时达到最大值,而在较高的烧结温度下,抗弯强度在TiN含量为6%时达到最大值;硬度在TiN含量≤10%时变化不明显, TiN含量>10%时硬度急剧下降;抗弯断口以穿晶解理为主要的断裂模式.更多还原

【Abstract】 Ti(C,N)/NiCr cermets were vacuum sintered by powder metallurgy technology. The effects of TiN additions on microstructures and mechanical properties of Ti(C, N)/NiCr cermets were investigated. Results revealed that the hard phase particles were refined and the morphology of the particles changed from a circular to a polygonal shape by the additions of TiN because of the formation of Ti(C,N) solid solution; With increasing TiN additions, the bonding strength increased to the maximum values at 4%TiN content during low sintering temperature and at 6%TiN content during high sintering temperature, respectively, and then decreased. Hardness changed little when TiN addition was less than 10%, but decreased dramatically when TiN addition exceeded 10%. Fracture photograph showed that trans-granular fracture was the main failure mode because of the good interface bonding strength between binding phase and ceramic hard phase.更多还原