Papers by Keyword: Sintering Characteristics

Abstract: The sintering temperature of coal ashes plays a great important role in the design and operation of fluidized-bed gasifier. The sintering temperatures (Ts) of Huolinhe lignite (HLH) ashes under different atmospheres and pressures were tested by self-made pressure-difference measuring system. The results show that the Ts under reducing atmosphere (H₂, CO or the mixture of 50% CO and H_2, volume ratio) are lower than those of under oxidizing atmosphere (O₂, CO₂, N₂). The Ts of HLH ashes decrease with the pressure increase, it changes slightly under low pressure, and decrease clearly under 0.7~1.0 MPa, after that, decrease slightly again with the pressure increase further.

Abstract: In order to enhance the density and decrease the sintering temperature，Al2O3/Si3N4 compound ceramics were sintered by pressureless using β- Si3N4 as raw materials and Al2O3 as sintering additives. The effects of Al2O3 as additive on the Vickers hardness and the sintering characteristic of Al2O3/Si3N4 compound ceramics were studied. The results shows that adding 9-15% nano- Al2O3 can get Al2O3/Si3N4 compound ceramics only in 1650°C by pressureless sintering because of nano- Al2O3’sintered. As a consequence, the relative density increases from 89% with micro alumina to above 97% with nano- Al2O3, the Vickers hardness increases from 1043.5MPa to 1356.0 MPa.

Abstract: In this paper, the fundamental attributes, phase composition of three pre-alloyed powders for diamond tools by water atomization were investigated. The density, hardness, bend strength and bending modulus of their sintered samples by hot pressing were examined under various temperatures. The results showed that the three pre-alloyed powders have excellent low temperature sintering characteristics. The physical and mechanical properties of the samples were found to be nearly the same as those of ultra-fine cobalt powders.