The cermet composites WC-20wt%Co/ZrO2（E6）with four different comtents of ZrO2（3Y）were prepared by normal vacuum sinter processing;the optical microscope and SEMwere used to characterize their microstructures.The h...The cermet composites WC-20wt%Co/ZrO2（E6）with four different comtents of ZrO2（3Y）were prepared by normal vacuum sinter processing;the optical microscope and SEMwere used to characterize their microstructures.The hardness.bending strength and impact toughness of the specimens were determined.The experimental results show that ZrO2（3Y） particles in WC-20wt%Co matrix are sphcrical particles in different sizes which are distributed uniformly in Co phases and WC phases,the bending strength and impact toughness of the WC-20wt%Co cermet composites added ZrO2（3Y）improve remarkably.but the hardness values have little change.展开更多
An attractive way to prepare W/TaC based cermet at a relatively low temperature was proposed and confirmed experimentally. The thermodynamics calculations indicated that the reaction between WC and Ta2O5was feasible a...An attractive way to prepare W/TaC based cermet at a relatively low temperature was proposed and confirmed experimentally. The thermodynamics calculations indicated that the reaction between WC and Ta2O5was feasible at as low a temperature as 1 400 ℃. The experimental results showed that W/TaC cermet could be fabricated by in-situ reaction sintering process at 1400 ℃ for 2 h in vacuum. The open porosity and bulk density of the W/TaC cermet were 15.3% and 13.4 g/cm3. Further, the microstructural features revealed that W, TaC, and Ta2WO8were identified to be the main constituents of the W/TaC cermet. The mass lose rate and linear recession rate of the W/TaC cermet during an oxyacetylene torch test were 0.0048 g/s and 0.0233 mm/s, respectively. The high porosity, the presence of Ta2WO8phases within W/TaC and evaporation of WO3on the surface of the composite contributed to the decrease of ablative property when comparing with pure W.展开更多
文摘The cermet composites WC-20wt%Co/ZrO2（E6）with four different comtents of ZrO2（3Y）were prepared by normal vacuum sinter processing;the optical microscope and SEMwere used to characterize their microstructures.The hardness.bending strength and impact toughness of the specimens were determined.The experimental results show that ZrO2（3Y） particles in WC-20wt%Co matrix are sphcrical particles in different sizes which are distributed uniformly in Co phases and WC phases,the bending strength and impact toughness of the WC-20wt%Co cermet composites added ZrO2（3Y）improve remarkably.but the hardness values have little change.
基金Funded by the Aid Program for Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Provincethe Aid Program for Innovative Research Team in National University of Defense Technology
文摘An attractive way to prepare W/TaC based cermet at a relatively low temperature was proposed and confirmed experimentally. The thermodynamics calculations indicated that the reaction between WC and Ta2O5was feasible at as low a temperature as 1 400 ℃. The experimental results showed that W/TaC cermet could be fabricated by in-situ reaction sintering process at 1400 ℃ for 2 h in vacuum. The open porosity and bulk density of the W/TaC cermet were 15.3% and 13.4 g/cm3. Further, the microstructural features revealed that W, TaC, and Ta2WO8were identified to be the main constituents of the W/TaC cermet. The mass lose rate and linear recession rate of the W/TaC cermet during an oxyacetylene torch test were 0.0048 g/s and 0.0233 mm/s, respectively. The high porosity, the presence of Ta2WO8phases within W/TaC and evaporation of WO3on the surface of the composite contributed to the decrease of ablative property when comparing with pure W.
