直流磁场下双金属复层铸坯制备

Bimetal-Clad Slab Preparation in Direct Current Magnetic Field

借助工程应用软件FLUENT誖,模拟研究了直流磁场对双金属复层铸坯制备过程金属液流动的影响规律,依据模拟优化的工艺参数,成功制得复层铝合金铸坯。结果表明,直流磁场可以有效抑制浇注入口金属液流速度,减少其射流深度,同时还可以有效控制铸型中心处出现的回流区;电磁制动效果随着磁场强度B增大而明显增加,但是当B达到某一临界值后,继续增加B,电磁制动效果增加幅度不大;在200mm·min-1的拉坯速度下给铸型宽度方向施加0.15T直流磁场,能使两种金属液体流动平稳,不发生混流。在此工艺参数下,实验中成功制备了双金属复层铝合金铸坯。

The effeots of DC （Direct Current） magnetic field on the molten metal flow during the preparation of clad metal are numerically studied with the engineering software FLUENT . The cladding billet of aluminum alloys was successfully produced by using the processing parameters obtained from the simulation optimization. The simulation and experimental results show that, by imposing the DC magnetic field, the poudng velocity from the nozzle is suppressed, the jet depth is decreased, and the bsck flow z.one in the center of the mould is reduced; with increasing of the magnetic intensity （B）, tho electromagnetic braking effects increase significantly, however the braking effects no longer increase lifter B reaches a critical value under a fixed withdrawal rate; at billet drawing speed of 200 mm .men^-1, the mixing of different alloys in the molten pool can be effectively constrained in 0.15 T DC magnetic field. According to the optimization parameters, the cladding billet of AI-Si and AI-Mg alloys was successfully produced, which validated the simulation model.