Numerical Simulations of the Ohno Continuous Casting Process for Mg - based Amorphous Alloys

Abstract

The Ohno continuous casting process for the Mg-based amorphous alloy is simulated using the finite element method. The influences of the temperature in the mold mouth, the cooling distance and the casting rate on the temperature field and the shape of the solid-liquid interface are investigated. It is found that when the temperature in the mold mouth increases from 800°C to 950°C, the convexity of the solid-liquid interface is gradually decreasing and the position of the interface is moving outward along the mold. When the cooling distance is extended from 45 mm to 85 mm, the profile of the solid-liquid interface has little change while its corresponding position is gradually far away from the mold mouth. When the casting rate increases from 1.33×10−4 m·s−1 to 3.33×10−4 m·s−1, the solid-liquid interface is moving back and forth toward the outside and inside of the mold mouth. The optimal process parameters in the Ohno continuous casting process identified in the simulations are 900°C for the temperature in the mold mouth, 2.50×10−4 m·s−1 for the casting rate and 60 mm for the cooling distance. The change in the temperature with the time under the optimum parameters is also obtained and the results indicate that the temperature drops rapidly at the very early process and then keeps almost the constant.