Lists the powders used and their properties. Particle size was determined by using the laser diffraction method (Microtrac S3500), and the oxygen content was determined by using an oxygen/nitrogen analyzer (LECO TC600). TiB2 or TiB2 and SiC powder mixtures were balls milled in isopropyl alcohol with either cemented carbide (6% Co) or SiAlON (Kennametal KY2000 grade) milling media for eighth and 24 h. The powder slurry was dried in a vacuum and screened, and the screened powders (50 mesh) were hot. It can be seen that even at a high hot pressing temperature of 1950 °C, pure TiB2 milled with SiAlON media was only sintered to a low relative density of ~ 80%.
On the contrary, TiB2 milled with W.C./Co media and TiB2–SiC composites milled with either W.C./Co or SiAlON media achieved relative density > 92% in the temperature range of 1800 °C to 1950 °C. Both W.C. and SiC can significantly improve the sinterability of the TiB2. The sinterability of TiB2 with high oxygen content was greatly improved by W.C./Co inclusion introduced during the milling process, which can be attributed to the elimination of the surface oxide layer and the formation of a liquid phase. During liquid phase sintering, a core/rim structure with pure TiB2 as the core and a solid solution of (Ti, W)B2 as the rim. The bonding strength between TiB2/(Ti, W)B2 was strong, as no intergranular fracture can be observed at the core. If you are looking for high quality, high purity, and cost-effective zinc sulfide, or if you require the latest price of zinc sulfide, please feel free to email contact mis-asia.
