The effects of CaO content in the range from 0 to 4.0%, and sintering temperature on the phase composition, relative density and electrical conductivity of 10NiO-NiFe2O4 composites doped with CaO were studied. The res...The effects of CaO content in the range from 0 to 4.0%, and sintering temperature on the phase composition, relative density and electrical conductivity of 10NiO-NiFe2O4 composites doped with CaO were studied. The results show that there is no change of structure for NiO or NiFe2O4; there is apparent oxygen absorbing and releasing behavior during the heating process in air for 10NiO-NiFe2O4 composites. Introduction of CaO can accelerate the densification of 10NiO-NiFe2O4 composites. The maximum value of relative density is 98.75% for composite doped with 2.0% CaO and sintered at 1 200 ℃, which is beyond about 20% for the undoped composites. The sintering activated energy of sample containing 2% CaO decreases by 15.87 kJ/mol, compared with that of the undoped sample.展开更多
It was reported that TiB2 gains grew fast during sintering was a main cause for its properties degrading. In this paper the HP-sintering mechanics of TiB2 was studied and the results show that grains grow very fast wh...It was reported that TiB2 gains grew fast during sintering was a main cause for its properties degrading. In this paper the HP-sintering mechanics of TiB2 was studied and the results show that grains grow very fast when the sintering temperature is near 1800℃ . From the sintering dynamics, it can be concluded that grain fast growing results in boundary-transporting processing, during which grain boundary work as fast tunnel for material transporting.展开更多
基金Project (2005CB623703) supported by the National Key Fundamental Research and Development Program of ChinaProject (50474051) supported by the National Natural Science Foundation of ChinaProject (03JJY3080) supported by the Natural Science Foundation of Hunan Province, China
文摘The effects of CaO content in the range from 0 to 4.0%, and sintering temperature on the phase composition, relative density and electrical conductivity of 10NiO-NiFe2O4 composites doped with CaO were studied. The results show that there is no change of structure for NiO or NiFe2O4; there is apparent oxygen absorbing and releasing behavior during the heating process in air for 10NiO-NiFe2O4 composites. Introduction of CaO can accelerate the densification of 10NiO-NiFe2O4 composites. The maximum value of relative density is 98.75% for composite doped with 2.0% CaO and sintered at 1 200 ℃, which is beyond about 20% for the undoped composites. The sintering activated energy of sample containing 2% CaO decreases by 15.87 kJ/mol, compared with that of the undoped sample.
基金Supported by National Excellent Young Scientist Fund (59925207)and National Natural Science Fundation(59802008)
文摘It was reported that TiB2 gains grew fast during sintering was a main cause for its properties degrading. In this paper the HP-sintering mechanics of TiB2 was studied and the results show that grains grow very fast when the sintering temperature is near 1800℃ . From the sintering dynamics, it can be concluded that grain fast growing results in boundary-transporting processing, during which grain boundary work as fast tunnel for material transporting.
