[T15] Hard Materials

[16P-T15-07] Effects of Mechanical Ball Milling and Calcination on the Mechanical Properties of Mo₂NiB₂-Ni cermets

*S. Kawasumi¹, S. Ichijo¹, Y. Harada¹, E. Takahashi¹, R. Sato¹, S. Maruyama¹ (1.Tokyo City University, Japan)

Keywords:Cermets, Boride,Mechanical Properties

Mo2NiB2-Ni cermets have been sintered using “Reaction Boronising Sintering (RBS)” proposed by K. Takagi. In RBS, the generation of an inhomogeneous microstructure of the boride phase occurs. In this study, the calcination and mechanical milling processes were introduced into the sintering process of Mo2NiB2-Ni cermets to separate the phase formation and densification and refine the microstructure. According to SEM observations, the porosity and grain size was reduced after calcination. It was also found that cermets with higher transverse fracture strength (TRS) and hardness were obtained. In addition, changes in the sintering process resulted in lower optimum sintering temperatures for obtaining these properties.