| In this paper,on the basis of systematically studying the characteristics of soft-contact electromagnetic confinement (SCEMC) and solidified structure for special alloys by using self-made EMCS experiment apparatus with wide range of velocity and taking superalloy as materials, the process of SCEMC and directional solidification for special alloys under vacuum and strongly cooling condition is brought up, its characteristics are short-circuiting manufacture process, minimizing pollution, decreasing the dendrite arm spacing, near-net shaping and simplifying operation. The main results are presented as following.The relationship between melt shape, magnetic field in the inductor and electromagnetic pressure acting on the melt surface is researched for SCEMC process, and the relationship between inductor structure, magnetic mold, susceptors structure and magnetic field in the inductor is questioned also. The characteristics of SCEMC process is not only analyzing, but also SCEMC process is investigated by simulating experiment. According to the specialty of SCEMC, the system of inductor-susceptors-melt is firstly established. On the basis of systematically studying the characteristics of SCEMC, two new approaches are proposed for special alloys. The results can be summarized as follows. The characteristics of SCEMC are minimizing pollution, shaping complex cross-section form, simplifying operation. When higher frequency is selected and the relationship between the inductee structure ,magnetic mold and susceptors structure is rational, the SCEMC for special alloys will be performed. Under experiment condition, when voltage in 120v~160v, the inductor height 27.5mm, melt static height 22.5mm, susceptors height 8mm and placed on the bottom of the inductor, the height of the melt menicus will be 12mm- 16mm and the height of melt soft-contact will be average 11.5mm, which assure the process of SCEMC and solidified structure. The near-net shape blade superalloy casting is successfully obtained by SCEMC process of solidified samples moved with magnetic mold.The characteristics of particulate movement in the fluidized bed is systematically studied, the system of the particulate fluidized is designed. On thebasis of analyzing heat transfer course in the fluidized bed, the heat transfer model is established. Based on cooling characteristics and technical parameters by experiments, the strongly cooling process of SCEMC and directional solidification for special alloys under vacuum is presented. Considering the drawing, the melt super heat, solidification latent heat, magnetic mold, fluidized particulates pouring quantity, paniculate characteristics and other factors on heat transfer course, the cooling model of SCEMC and directional solidification is founded. The results show that particulates movement in the fluidized bed can be controlled by gas velocity and changing particulate diameter, decreasing particulates diameter and density is a effective method of particulates fluidized under vacuum condition. In fluidized bed, the main mechanism of transfer between bed and surfaces are particle convection and gas convection; when particle convection is the main transfer mechanism under appropriate gas velocity, heat transfer coefficient will be maximum. Under the experiment condition, when motionless height of 100# SiC particles is 60~80mm, the cooling power of fluidized bed is in advance of liquid metal, which is gradually decreased on fluidized bed height. The superalloy flat and cylindric samples with solidified structure first dendrite arm spacing 80um and 60um are obtained under liquid nitrogen pressure 0.3Pa and 100#SiC particle condition. Heat transfer efficiency can be effectively improved by increasing melt supertemperature, selecting suited drawing velocity, raising the position of cooling point, increasing fluidized particle pouring quantity, selecting correct particulate and magnetic mold.Considering current density, the drawing, solidification latent heat and other factors on SCEM...
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