CAFE simulation of directional solidification structure of low nickel austenitic stainless steel
(2.Rare Earth Steel Plate Company, Baotou Steel Group, Baotou, Inner Mongolia, China 014010)
【Abstract】In this paper, through the secondary development of ProCAST & CAFE software, the dynamic boundary conditions of solidification process are established; the temperature field and solid fraction in the directional solidification process of low nickel austenitic stainless steel are simulated; the effect of the withdrawing rate on the solidification microstructure is discussed. The results shows that the withdrawing rate is in the range of 15–200 μm/s; as the solidification rate increases, the isotherm becomes dense, gummy zone narrowing. Additionally, as the solidification rate increases, the primary dendrite arm gradually refines and the secondary dendrite arm becomes dense and coarse. In addition, as the withdrawing rate increases in the range from 15 to 200 μm/s, the lateral heat dissipation of the edge of the casting is gradually smaller than that of the central longitudinal heat dissipation, and the axial deviation of the dendrites is reduced from 27.66° to 25.964°. At the same time, the comparative analysis simulation results are in good agreement with the experimental results, and the simulation calculation process is more reasonable.
【Keywords】 liquid metal cooling; austenitic stainless steel; numerical simulation; microstructure;
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