Ultra-fine titanium carbonitride （TiCN） matrix materials with a grain size less than 1μm were successfully prepared by vacuum microwave sintering. The milling process for raw TiCN particles and the microstructure a...Ultra-fine titanium carbonitride （TiCN） matrix materials with a grain size less than 1μm were successfully prepared by vacuum microwave sintering. The milling process for raw TiCN particles and the microstructure and properties of cermets produced with a composition of 15wt.%WC-17wt.%（Co＋Ni）-9wt.%Mo2C-59wt.%Ti0.TN0.3 and sintered by vacuum microwave were analyzed by scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The results show that a ball-to-powder mass ratio of 8：1 and a milling time of 50 h provided appropriate conditions for the production of ultra-fine TiCN solid solution powders. The use of vacuum microwave sintering produced cermets with much finer grain and black core structures and higher relative density and hardness than those produced by vacuum sintering technology.展开更多
The oxidation behavior of 0. 8% La2O3- Mo5Si3/MoSi2 composites at 1200℃ in air was investigated. The results reveal that the oxidation resistance of the material with 0. 8% La2O3 and Mo5Si3 is impaired. The oxidation...The oxidation behavior of 0. 8% La2O3- Mo5Si3/MoSi2 composites at 1200℃ in air was investigated. The results reveal that the oxidation resistance of the material with 0. 8% La2O3 and Mo5Si3 is impaired. The oxidation resistance is decreased with increasing Mo5Si3 content. The mass loss follows a linear law in the initial oxidation. With oxidation time prolonging, a continuous and dense oxidation scale prevents oxygen from diffusing increasing when and leads to mass change a Mo5Si3 content is less than 30%. However, the composite shows ＂PEST＂ with the addition of 40% Mo5Si3. With increasing Mo5Si3 content, the oxidation resistance of 0.8% La2O3- Mo5Si3/MoSi2 decreases. This attributes to the poor oxidation resistance of M05Si3 and the relative density decreasing of 0. 8% La2O3-Mo5Si3/MoSi2 composite.展开更多
基金supported by the Hunan Provincial Natural Science Fund for Distinguished Young Scholars of China(No.08JJ1007)the Hunan Provincial Key Science Research Program of China(No.2008GK2009)the Scientific Research Fund of Fujian Provincial Education Department of China(No.JK2009029)
文摘Ultra-fine titanium carbonitride （TiCN） matrix materials with a grain size less than 1μm were successfully prepared by vacuum microwave sintering. The milling process for raw TiCN particles and the microstructure and properties of cermets produced with a composition of 15wt.%WC-17wt.%（Co＋Ni）-9wt.%Mo2C-59wt.%Ti0.TN0.3 and sintered by vacuum microwave were analyzed by scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The results show that a ball-to-powder mass ratio of 8：1 and a milling time of 50 h provided appropriate conditions for the production of ultra-fine TiCN solid solution powders. The use of vacuum microwave sintering produced cermets with much finer grain and black core structures and higher relative density and hardness than those produced by vacuum sintering technology.
文摘The oxidation behavior of 0. 8% La2O3- Mo5Si3/MoSi2 composites at 1200℃ in air was investigated. The results reveal that the oxidation resistance of the material with 0. 8% La2O3 and Mo5Si3 is impaired. The oxidation resistance is decreased with increasing Mo5Si3 content. The mass loss follows a linear law in the initial oxidation. With oxidation time prolonging, a continuous and dense oxidation scale prevents oxygen from diffusing increasing when and leads to mass change a Mo5Si3 content is less than 30%. However, the composite shows ＂PEST＂ with the addition of 40% Mo5Si3. With increasing Mo5Si3 content, the oxidation resistance of 0.8% La2O3- Mo5Si3/MoSi2 decreases. This attributes to the poor oxidation resistance of M05Si3 and the relative density decreasing of 0. 8% La2O3-Mo5Si3/MoSi2 composite.
