In recent years, many Ni-containing materials manufactured from laterite have played a significant role in supporting the rapid development of the stainless steel industry in China. Currently ,pyrometallurgy is the ma...In recent years, many Ni-containing materials manufactured from laterite have played a significant role in supporting the rapid development of the stainless steel industry in China. Currently ,pyrometallurgy is the main process for laterite smelting, where blast furnaces are employed to make Ni-containing hot metal. With the aim of giving some references for making good use of laterite, technical and economic analysis was conducted in this paper, based on the discussion of the key technologies of Ni-containing hot metal production with laterite （50.4% Fe） in blast furnaces.展开更多
Ni-containing carbon films were prepared by rf glow discharge decomposition of methane and nickel carbonyl. The deposited des contained C, Ni, H, O and small amounts of N. Nickel existed in forms of metric Ni and Ni2O...Ni-containing carbon films were prepared by rf glow discharge decomposition of methane and nickel carbonyl. The deposited des contained C, Ni, H, O and small amounts of N. Nickel existed in forms of metric Ni and Ni2O3. The oxidation of nickel mainly occurred on film surface. With lower Ni contents, the film maintained the structure of DLC film. With the increase of Ni content, the films showed some crystalline features of Ni and Ni2O3.展开更多
It has been widely demonstrated that addition of Ni in low-carbon steels can effectively improve the cryogenic toughness, but the mechanism behind it has yet to be clarified. In the present work, the evolutions of mic...It has been widely demonstrated that addition of Ni in low-carbon steels can effectively improve the cryogenic toughness, but the mechanism behind it has yet to be clarified. In the present work, the evolutions of microstructure and mechanical properties after quenching and tempering for Ni-containing cryogenic steels with different Ni contents （3.5-9 wt%） were investigated. The results showed that after quenching and tempering, the Ni-containing cryogenic steels were composed of tempered martensite and reversed austenite. The volume fraction of reversed austenite has increased from 0 up to 6.3% when the Ni content increases from 3.5% to 9%. The Charpy impact tests indicated that the low- temperature toughness was markedly improved with the increase in Ni content, which can be correlated with the increase in reversed austenite amount. The main contribution of reversed austenite to the toughness lies in： （1） the elimination of cementite precipitates improved the plastic deformation capacity of matrix, and （2） the crack propagation is hindered through plastic deformation.展开更多
文摘In recent years, many Ni-containing materials manufactured from laterite have played a significant role in supporting the rapid development of the stainless steel industry in China. Currently ,pyrometallurgy is the main process for laterite smelting, where blast furnaces are employed to make Ni-containing hot metal. With the aim of giving some references for making good use of laterite, technical and economic analysis was conducted in this paper, based on the discussion of the key technologies of Ni-containing hot metal production with laterite （50.4% Fe） in blast furnaces.
文摘Ni-containing carbon films were prepared by rf glow discharge decomposition of methane and nickel carbonyl. The deposited des contained C, Ni, H, O and small amounts of N. Nickel existed in forms of metric Ni and Ni2O3. The oxidation of nickel mainly occurred on film surface. With lower Ni contents, the film maintained the structure of DLC film. With the increase of Ni content, the films showed some crystalline features of Ni and Ni2O3.
基金supported by the Fundamental Research Funds for the Central Universities(No.N120807001)the National High-tech Research and Development Program of China (863 Program)(No.2007 AA03Z504)
文摘It has been widely demonstrated that addition of Ni in low-carbon steels can effectively improve the cryogenic toughness, but the mechanism behind it has yet to be clarified. In the present work, the evolutions of microstructure and mechanical properties after quenching and tempering for Ni-containing cryogenic steels with different Ni contents （3.5-9 wt%） were investigated. The results showed that after quenching and tempering, the Ni-containing cryogenic steels were composed of tempered martensite and reversed austenite. The volume fraction of reversed austenite has increased from 0 up to 6.3% when the Ni content increases from 3.5% to 9%. The Charpy impact tests indicated that the low- temperature toughness was markedly improved with the increase in Ni content, which can be correlated with the increase in reversed austenite amount. The main contribution of reversed austenite to the toughness lies in： （1） the elimination of cementite precipitates improved the plastic deformation capacity of matrix, and （2） the crack propagation is hindered through plastic deformation.
