Experimental Research on Oxidation Refining of Ferrosilicon

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.

Evaluation of Component Activity in Molten MnO-SiO_(2)-Al_(2)O_(3)-CaO System with Model SELF-SReM4

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.

Kinetics of Reduction of M nO in Molten Slag with Carbon Undersaturated Liquid Iron

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.

Decarburization of Fe-C Melt by Pressured Oxygen

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.

Reduction Mechanism of Chromite Ore in Blast Furnace

The structural changes and reduction degree of chromite ore in blast furnace were studied by optical micrograph analysis,scanning electron microscope(SEM)and energy dispersive X-ray analysis(EDXA).The smelting reduction mechanism of chromite in blast furnace was primarily discussed.

Investigation on Dephosphorization of Stainless Steel

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.

Temperature Dependence of the Raman Spectra of Na_(2)Si_(2)O_(5)

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.

Temperature Dependence of the Raman Spectra and Phase Transition of Zirconia

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.

A Molecular Dynamics Simulation of CaSiO3 Melt Under an Electric Field

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.