[T15] Hard Materials

[16P-T15-04] Influence of TiB₂ Powder Sizes on the Microstructures and Mechanical Properties of Ni-TiB₂ Composites

*Q. Li¹, K. Matsugi¹, Z. Xu², Y. Choi¹, J. Yu² (1.Hiroshima University, Japan, 2.Yanshan University, China)

キーワード：Ni-TiB2, SPS, Particle size, mechanical properties

The TiB₂ is difficult to sinter densely because of its low self-diffusion coefficient and high melting point. Usually, using metals as the binder phase to lower the sintering temperature. In the current study, metal-TiB₂ composites were prepared by SPS sintering at temperatures higher than 1500℃. Here, We prepare TiB₂–10Ni composites with different TiB₂ particle size (S-TiB₂, 3μm; L-TiB₂, 63μm) were fabricated by SPS sintering at 1100℃ and 1200℃ with 60MPa pressure, and obtained composites with 99.6% relative density. The experimental results showed that only TiB₂ and Ni phases in the TiB₂-Ni composites, the hardness of the composite can reach 2121HV and has good toughness. Mixing TiB₂ powders of different particle sizes in certain proportions can make it easier to sinter densely at lower temperatures and obtain harder, tougher composites.