Numerical Simulation Of Electromagnetic Centrifugal Casting Coupling Heat-flow-magnetic

Roll is a tool to make plastic deformation for rolling metal, and is an importantconsumption part in determining the quality and efficiency of rolling mill. Due to goodabrasion resistance and its characteristics different from traditional roll, high speed steel roll iswidely used in the production of steel rolling. At present, because of its high productionefficiency, good strength and many other advantages, centrifugal casting method is widelyused for producing high speed steel compound roll in China. If electromagnetic stirring is putinto the centrifugal casting of high speed steel roll, it will achieve the objectives of improvingas-cast organization, reducing segregation and enhancing roll performance. But it’s difficult toobserve and measure the filling patterns of liquid metal owing to the complex stress, highspeed and temperature and not transparent of centrifugal casting. The application of computernumerical simulation technology provides a new method for researchers understanding ofcentrifugal casting filling and solidification process, also provide important guidance for theoptimization design of casting process.In this paper, the horizontal centrifugal casting of high speed steel compound roll outerlayer is set as the research object, and the numerical simulation and analysis of filling andsolidification process in centrifugal casting and electromagnetic centrifugal casting couplingheat-flow-magnetic are made by using CFD software Fluent, moreover, the outcomes arepartially validated by the experiment. The purpose is to explore the basic rule of filling andsolidification process in the centrifugal casting and electromagnetic centrifugal casting andresearch the influence on filling and solidification process in a centrifugal casting made byelectromagnetic fields. The main results are as follows:Under the combined effect of gravity, centrifugal force and electromagnetic force，thethree dimensional solidification process mathematical model and physical model couplingheat transfer and flow of molten metal in horizontal centrifugal casting on high speed steelcomposite roll was established, and the boundary conditions need to be considered are set.The flow field analysis results show that molten metal flows into the casting mould ofhigh speed spinning from the sprue in the form of a parabola, and then makes the axialmovement in the form of a helix closed to the inside mould wall. The maximum speed ofmolten metal is as same as that of the casting mould inner layer. Furthermore, the free surfaceof molten metal is eccentrically distributed because of the existence of pressure difference,and this eccentric phenomenon will be weakened with the increase of revolving speed, whichis proved by the experiment. The results of the analysis about temperature filed indicate that the temperaturedistribution of high speed steel composite roll is non-uniform in the solidification process, andthe solidification sequence is from both ends up to middle part in the axial direction and isfrom outer diameter to inner diameter of the roll in the radial direction. In addition, the fasterthe casting mould rotates, the greater the temperature drops.The electromagnetic is introduced into centrifugal casting, and the calculation couplingelectromagnetic, flow and heat transfer has been carried on, which is compared with results ofsimulation calculation in the absence of any magnetic field. The analysis results turn out thatin the same spot for a certain pouring time, the absolute pressure of molten metal on theinternal wall of casting mould has certain differences between electromagnetic centrifugalcasting and ordinary centrifugal casting and flow rate of molten metal will slow down due tothe electromagnetic force, which confirms that the electromagnetic force has played a role instirring the flow inside the mould.