Sintering and Toughening Behavior of Dense SiC-coated Diamond Dispersed WC/Co Composites(Materials, Metallurgy & Weldability)
Search this Article
Hard protective layers of nanometer sized SiC grains to protect against oxidation and graphitization were coated on diamond particles by the reaction of SiO and diamond. The SiC coated diamond particles were mixed in 2O vol.% with WC-10wt.%Co and densified by using the SPS method. The sintering behavior in respect of the particle size of diamond, 8〜16μm, 2O〜3Oμm and 40〜60μm, was investigated. The relative densities of all composites reached 98%. The Vickers hardness increased slightly to 17.9GPa by dispersing 40〜60μm size diamond, but did not differ so much from the matrix hardness of WC/Co, this suggests no direct bonding between diamond particles, and weak bonding between diamond and matrix. However, the indentation toughness increased from 9.4MPam^<1/2> to 17.8MPam^<1/2> with diamond dispersion. Crack deflection, debonding and stopping were clearly seen around diamond particles.
- Transactions of JWRI
Transactions of JWRI 32(2), 303-308, 2003-12