Composite powders of nanocrystalline WC-10Co (15wt%),Y2O3 (8mol%) stabilized nanocrystalline ZrO2 (30wt%),industrial cobalt powder (4.5wt%) and submicron Al2O3 (55wt%) composite powders were fabricated by hi...Composite powders of nanocrystalline WC-10Co (15wt%),Y2O3 (8mol%) stabilized nanocrystalline ZrO2 (30wt%),industrial cobalt powder (4.5wt%) and submicron Al2O3 (55wt%) composite powders were fabricated by high-energy ball-milling process.The nanocomposite powders were consolidated by microwave sintering process at temperature ranged 1300℃-1550℃ for 15min,respectively.The optimum consolidation conditions,such as temperature,were researched during microwave sintering process.Vickers Hardness of the consolidated cermets was measured by using a Vickers indentation test,and density of specimens was also determined by Archimedes' principle.Microwave sintering process could not only increase the density of Al2O3-ZrO2-WC-Co cermets and reduce the porosity,but also inhibit abnormal grain growth.展开更多
Y2O3-doped TiCN-based cermets were prepared by pressureless sintering with powders TiC, TiN, Ni, etc. as main starting materials. The influence of sintering processes and Y2O3 on properties of TiCN-based cermets were ...Y2O3-doped TiCN-based cermets were prepared by pressureless sintering with powders TiC, TiN, Ni, etc. as main starting materials. The influence of sintering processes and Y2O3 on properties of TiCN-based cermets were investigated. The phase composition of TiCN-based cermets almost had no change with Y2O3 addition. The fullly densified TiCN-based cermets were achieved by P-2 sitering process. The fracture surface showed lots of small dimples caused by hard phase particles pulling-off, and the left hard phase particles were attached to the arborous dendritic matrix. The Vickers hardness, fracture toughness and bending strength of TiCN-based cermets increased firstly and then decreased with the increment of Y2O3 content. When Y2O3 contents were both 0.8 wt.%, compared with the P-1 sintered samples, the Vickers hardness, fracture toughness and bending strength of the P-2 sintered sampies reached 14.84 GPa, 8.66 MPa-m1/2 and 660.4 MPa, which were increased by 7.9%, 6.1% and 45.8%, respectively.展开更多
基金Funded by the Youth Science Plan for Light of the Morning Sun of Wuhan City (200750731270)
文摘Composite powders of nanocrystalline WC-10Co (15wt%),Y2O3 (8mol%) stabilized nanocrystalline ZrO2 (30wt%),industrial cobalt powder (4.5wt%) and submicron Al2O3 (55wt%) composite powders were fabricated by high-energy ball-milling process.The nanocomposite powders were consolidated by microwave sintering process at temperature ranged 1300℃-1550℃ for 15min,respectively.The optimum consolidation conditions,such as temperature,were researched during microwave sintering process.Vickers Hardness of the consolidated cermets was measured by using a Vickers indentation test,and density of specimens was also determined by Archimedes' principle.Microwave sintering process could not only increase the density of Al2O3-ZrO2-WC-Co cermets and reduce the porosity,but also inhibit abnormal grain growth.
基金supported by the Shaanxi Industrial Science and Technology Research(2014K08-09)the Scientific Research Program funded by Yulin city(2012)
文摘Y2O3-doped TiCN-based cermets were prepared by pressureless sintering with powders TiC, TiN, Ni, etc. as main starting materials. The influence of sintering processes and Y2O3 on properties of TiCN-based cermets were investigated. The phase composition of TiCN-based cermets almost had no change with Y2O3 addition. The fullly densified TiCN-based cermets were achieved by P-2 sitering process. The fracture surface showed lots of small dimples caused by hard phase particles pulling-off, and the left hard phase particles were attached to the arborous dendritic matrix. The Vickers hardness, fracture toughness and bending strength of TiCN-based cermets increased firstly and then decreased with the increment of Y2O3 content. When Y2O3 contents were both 0.8 wt.%, compared with the P-1 sintered samples, the Vickers hardness, fracture toughness and bending strength of the P-2 sintered sampies reached 14.84 GPa, 8.66 MPa-m1/2 and 660.4 MPa, which were increased by 7.9%, 6.1% and 45.8%, respectively.