EM - Escola de Minas
URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/6
Notícias
A Escola de Minas de Ouro Preto foi fundada pelo cientista Claude Henri Gorceix e inaugurada em 12 de outubro de 1876.
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2 resultados
Resultados da Pesquisa
Item Influence of synthetic slag added during the tapping on inclusion features of a vacuum degassed LCAK steel grade.(2020) Melo, Gilberson Mendonça Storck de; Silva, Carlos Antônio da; Peixoto, Johne Jesus Mol; Oliveira, José Roberto; Silva, Caio Vaccari; Silva, Itavahn Alves daSynthetic slag has been added during BOF tapping in order to modify the physicochemical properties of resulting slag with the aim of assessing the influence on inclusion density, composition and size distribution. Viscosities and activities of slag oxides were calculated by FactSage 7.2, using the FToxid database and Viscosity module. All heats were treated under vacuum in an RH degasser for 15 minutes. A comparative analysis of top slags with two levels of FeO+MnO (> 10% and ≤ 10%) was carried out. The higher level of FeO+MnO led to almost thrice more inclusion than the lower level. Top slags after treatment with synthetic slag brought the best result of inclusions features thanks to their higher CaO activity, lower viscosity and lower activity of Al2O3. These heats presented smaller inclusions and lower initial inclusion density at ladle arrival at RH. Based on these evidences, top slags with synthetic slags added during the tapping and FeO+MnO content ≤ 10% conferred the best condition in steel cleanliness.Item A physical modelling study of inclusion removal in tundish using inert gas curtain.(2012) Seshadri, Varadarajan; Silva, Carlos Antônio da; Silva, Itavahn Alves da; Araújo Júnior, Ely da SilvaThe control and minimization of non-metallic inclusions content in the tundish and in the mold of a continuous casting unit is crucial for ensuring the final quality of the steel cast product. Nonmetallic inclusions of sizes smaller than 15 m are hard to remove, as they are difficult to float. They are easily carried by the flow of steel melt into the mold and adversely affect the steel cleanliness. It is suggested that a gas curtain made of small bubbles of argon can be used to capture and remove these inclusions in the tundish, thus avoiding their transport into the mold. A 1:3 scale physical model of tundish of the continuous casting unit of ArcelorMittal plant, in Vitória, Brazil, was built to investigate the effects of gas flow, shape and positioning of the gas curtain inside the tundish, on the efficiency of removal of inclusions. The results suggest that the gas bubbling inside the tundish can be effective in inclusion removal. The efficiency is dependent upon the location of argon bubbling.