This paper explained the mechanism of carbon pickup by ultra low carbon steels during continuous casting and indicated that the major cause of carbon pickup is the contact of the molten steel with the enriched carb...This paper explained the mechanism of carbon pickup by ultra low carbon steels during continuous casting and indicated that the major cause of carbon pickup is the contact of the molten steel with the enriched carbon layer of the powder. Forming of the enriched carbon layer is due to the existing of “carbon core”. Accordingly, the measures to reduce the carbon content and amount of the enriched carbon layer were investigated. A kind of new powder has been developed and successfully used to minimize the carbon pickup by ultra low carbon steels during continuous casting.展开更多
A sub-regular solution model SELF-SReM4 used to evaluate activity of the components in a homogeneous region of a quaternary system has been developed in Shanghai Enhanced Laboratory of Ferrometallurgy.The application ...A sub-regular solution model SELF-SReM4 used to evaluate activity of the components in a homogeneous region of a quaternary system has been developed in Shanghai Enhanced Laboratory of Ferrometallurgy.The application of SELF-SReM4 in C-Mn-Fe-Si system without the SiC formation has been introduced in previous paper.It’s application for molten slag of MnO-SiO2-Al2O3-CaO was introduced in this paper.They provide a basis for the prediction of the metal-slag equilibrium conditions.展开更多
The reduction of MnO in molten s lag with carbon undersaturated iron was studied. It was found that the process i s affected by the carbon content of molten metal and the temperature. The higher the carbon content and...The reduction of MnO in molten s lag with carbon undersaturated iron was studied. It was found that the process i s affected by the carbon content of molten metal and the temperature. The higher the carbon content and the temperature, the faster both the reduction and the e merging of the hump on curve of ωFeO, the larger the difference betwe en ωFeO, max and ωFeO, e. The phenomena were explained wi th three-step reaction model.展开更多
According to the principle of electromagnetism and hydrodynamics, a mathematical model of flow field for metallic fluid acted by electromagnetic and centrifugal forces was established. The calculation results showed t...According to the principle of electromagnetism and hydrodynamics, a mathematical model of flow field for metallic fluid acted by electromagnetic and centrifugal forces was established. The calculation results showed that the relative velocity between metallic fluid layers rises and the absolute rotational velocity of metallic fluid falls with the increase of magnetic induction intensity. The increase of centrifugal revolution hardly affects the relative velocity between metallic fluid layers, but can enhance the absolute rotational velocity of metallic fluid.展开更多
The principle of the dephosphorization for stainless steels differs from that of other low alloy steels, which should not only decrease phosphorous content efficiently but also keep the concentration of Cr almost loss...The principle of the dephosphorization for stainless steels differs from that of other low alloy steels, which should not only decrease phosphorous content efficiently but also keep the concentration of Cr almost lossless. In these cases, two techniques can be selected. The strategy for oxidational dephosphorization is illustrated in terms of “the selective oxidation among elements ［Cr］, ［P］ and ［C］. So there are two critical W［C］ values. If the real W［C］ locates between these two critical values, the dephosphorization process will be optimized. The optimized region deduced theoretically coincides with the reported range very well. The experiment of reductional dephosphorization was carried out in a sealed reactor. The dephosphorization degree reached 55.4 %—78.0 % when the original phosphorous content was 0.04 %—0.05 %. The processing parameters and the way to avoid pollution were suggested. So this process seems to be possibly adopted in industrial scale.展开更多
The microstructures of Na_(2)Si_(2)O_(5) from room temperature up to 1773 K are studied by high temperature Raman spectroscopy.Deconvolutions of complex Raman spectra of crystal and amorphous states(glass and melt)are...The microstructures of Na_(2)Si_(2)O_(5) from room temperature up to 1773 K are studied by high temperature Raman spectroscopy.Deconvolutions of complex Raman spectra of crystal and amorphous states(glass and melt)are described.The results show that the temperature-dependent Raman spectra clearly indicate phase transition.Relative abundance of various kinds of SiO_(4) tetrahedrons(each Si binding to different number of bridging oxygens)can be qualitatively and quantitatively resolved as to be varied obviously with different temperatures.It manifests that high temperature Raman spectroscopy provides a useful tool for the microstructure research under high temperature and helps to explain the properties of silicate glasses and melts.展开更多
A newly constructed high-temperature Raman spectrometer was used to study the temperature-dependence Raman spectra(up to 2023 K)and transformation of zirconia crystal.High-temperature Raman scattering is a useful tool...A newly constructed high-temperature Raman spectrometer was used to study the temperature-dependence Raman spectra(up to 2023 K)and transformation of zirconia crystal.High-temperature Raman scattering is a useful tool in characterizing the different structures of zirconia and offers the possibility to identify the phase transformation.It shows that monoclinic zirconia transforms to tetragonal phase at about 1440 K during the process of increasing temperature,but shows a lower transformation temperature from tetragonal to monoclinic phase at about 1323 K while the temperature decreased.展开更多
The results of a molecular dynamics(MD)simulation are presented for CaSiO3 melt under an electric field.The two-body interaction potential is adopted in the simulation,with parameters chosen so that the calculated sta...The results of a molecular dynamics(MD)simulation are presented for CaSiO3 melt under an electric field.The two-body interaction potential is adopted in the simulation,with parameters chosen so that the calculated static structure is consistent with results of high temperature x-ray experiments.It is found that the MD results for the heat capacity at constant volume,the self-diffusion coefficient and the electrical conductivity change greatly when the electric field is over 500 MV/m.Discussion is given on these results,together with the frequency-dependent electrical conductivity.展开更多
The molten liquid discrete flow inside a packed bed is a typical transport phenomenon in the blast furnace. As for the reported mathematical models presenting the liquid discrete flow within the packed bed, there are ...The molten liquid discrete flow inside a packed bed is a typical transport phenomenon in the blast furnace. As for the reported mathematical models presenting the liquid discrete flow within the packed bed, there are some barriers for their application to an engineering scale-up, or some imperfections in model descriptions. To overcome these deficiencies, the effects of the packed bed on the liquid discrete flow have been divided into resistance action and dispersal action, and appropriate descriptions have been given for the two aetions, respectively. Consequently, a new mathematical model has been built to present the liquid discrete flow inside a coke bed in the blast furnace. The mathematical model can predict the distribution of liquid flux and the liquid flowing range inside the packed bed at any time. The prediction of this model accords well with the experimental data. The model will be much better for the simulation of the ironmaking process, compared with the existent model.展开更多
基金Project Sponsored by Natural Science Foundation of Shanghai(97XD14005)
文摘This paper explained the mechanism of carbon pickup by ultra low carbon steels during continuous casting and indicated that the major cause of carbon pickup is the contact of the molten steel with the enriched carbon layer of the powder. Forming of the enriched carbon layer is due to the existing of “carbon core”. Accordingly, the measures to reduce the carbon content and amount of the enriched carbon layer were investigated. A kind of new powder has been developed and successfully used to minimize the carbon pickup by ultra low carbon steels during continuous casting.
文摘A sub-regular solution model SELF-SReM4 used to evaluate activity of the components in a homogeneous region of a quaternary system has been developed in Shanghai Enhanced Laboratory of Ferrometallurgy.The application of SELF-SReM4 in C-Mn-Fe-Si system without the SiC formation has been introduced in previous paper.It’s application for molten slag of MnO-SiO2-Al2O3-CaO was introduced in this paper.They provide a basis for the prediction of the metal-slag equilibrium conditions.
文摘The reduction of MnO in molten s lag with carbon undersaturated iron was studied. It was found that the process i s affected by the carbon content of molten metal and the temperature. The higher the carbon content and the temperature, the faster both the reduction and the e merging of the hump on curve of ωFeO, the larger the difference betwe en ωFeO, max and ωFeO, e. The phenomena were explained wi th three-step reaction model.
基金Item Sponsored by National Natural Science Foundation of China and Baoshan Iron and Steel Co(50104007)Foundation forAuthor of National Excellent Doctoral Dissertation of China(200031)Shanghai Education Committee andShanghai Education Development Foundation“Shuguang”Project(01SG45)
文摘According to the principle of electromagnetism and hydrodynamics, a mathematical model of flow field for metallic fluid acted by electromagnetic and centrifugal forces was established. The calculation results showed that the relative velocity between metallic fluid layers rises and the absolute rotational velocity of metallic fluid falls with the increase of magnetic induction intensity. The increase of centrifugal revolution hardly affects the relative velocity between metallic fluid layers, but can enhance the absolute rotational velocity of metallic fluid.
基金Project Supported by the Shanghai Science&Technology Development Foundation(G 01158)
文摘The principle of the dephosphorization for stainless steels differs from that of other low alloy steels, which should not only decrease phosphorous content efficiently but also keep the concentration of Cr almost lossless. In these cases, two techniques can be selected. The strategy for oxidational dephosphorization is illustrated in terms of “the selective oxidation among elements ［Cr］, ［P］ and ［C］. So there are two critical W［C］ values. If the real W［C］ locates between these two critical values, the dephosphorization process will be optimized. The optimized region deduced theoretically coincides with the reported range very well. The experiment of reductional dephosphorization was carried out in a sealed reactor. The dephosphorization degree reached 55.4 %—78.0 % when the original phosphorous content was 0.04 %—0.05 %. The processing parameters and the way to avoid pollution were suggested. So this process seems to be possibly adopted in industrial scale.
基金Supported by the National Natural Sciences Foundation of China under Grant Nos.59874016 and 59832080the Shanghai Research Center for Advanced Materials under Grant No.98JC14018Shanghai Educational Council.
文摘The microstructures of Na_(2)Si_(2)O_(5) from room temperature up to 1773 K are studied by high temperature Raman spectroscopy.Deconvolutions of complex Raman spectra of crystal and amorphous states(glass and melt)are described.The results show that the temperature-dependent Raman spectra clearly indicate phase transition.Relative abundance of various kinds of SiO_(4) tetrahedrons(each Si binding to different number of bridging oxygens)can be qualitatively and quantitatively resolved as to be varied obviously with different temperatures.It manifests that high temperature Raman spectroscopy provides a useful tool for the microstructure research under high temperature and helps to explain the properties of silicate glasses and melts.
基金Supported by the National Natural Sciences Foundation of China under grant Nos.59874016 and 59832080the Shanghai Research Center for Advanced Materials under grant No.98JC14018 and Shanghai Educational Council.
文摘A newly constructed high-temperature Raman spectrometer was used to study the temperature-dependence Raman spectra(up to 2023 K)and transformation of zirconia crystal.High-temperature Raman scattering is a useful tool in characterizing the different structures of zirconia and offers the possibility to identify the phase transformation.It shows that monoclinic zirconia transforms to tetragonal phase at about 1440 K during the process of increasing temperature,but shows a lower transformation temperature from tetragonal to monoclinic phase at about 1323 K while the temperature decreased.
基金Supported by the National Natural Sciences Foundation of China under Grant Nos.59874016 and 59832080the Shanghai Research Center for Advanced Materials under Grant No.98JC14018Shanghai Sciences Foundation of Youth.
文摘The results of a molecular dynamics(MD)simulation are presented for CaSiO3 melt under an electric field.The two-body interaction potential is adopted in the simulation,with parameters chosen so that the calculated static structure is consistent with results of high temperature x-ray experiments.It is found that the MD results for the heat capacity at constant volume,the self-diffusion coefficient and the electrical conductivity change greatly when the electric field is over 500 MV/m.Discussion is given on these results,together with the frequency-dependent electrical conductivity.
基金Item Sponsored by National Natural Science Foundation of China(50704040)
文摘The molten liquid discrete flow inside a packed bed is a typical transport phenomenon in the blast furnace. As for the reported mathematical models presenting the liquid discrete flow within the packed bed, there are some barriers for their application to an engineering scale-up, or some imperfections in model descriptions. To overcome these deficiencies, the effects of the packed bed on the liquid discrete flow have been divided into resistance action and dispersal action, and appropriate descriptions have been given for the two aetions, respectively. Consequently, a new mathematical model has been built to present the liquid discrete flow inside a coke bed in the blast furnace. The mathematical model can predict the distribution of liquid flux and the liquid flowing range inside the packed bed at any time. The prediction of this model accords well with the experimental data. The model will be much better for the simulation of the ironmaking process, compared with the existent model.
