Develop a Novel Pouring Cup with Pulsed Magnetic Field Treatment Based on Simulation to Improve the Solidification Microstructure and Properties for Sand Castings

The microstructure and mechanical properties were improved of sand castings using a novel pouring cup developed with pulsed magnetic field (PMF) treatment. Numerical simulation was performed to visualize the internal magnetic field, temperature field, and metal flow under the effect of PMF and to determine the pouring cup’s structure and process parameters of PMF. The results showed that the interior configuration of the winding can handle a larger volume of molten metal. When the magnetic field was reversed at 200 A current, 20 Hz, and 50 pct duty cycle, the intensity and penetration depth of the magnetic field density (MFD) increased. Conversely, the MFD decayed exponentially when the distance increased. Melt velocity increased under PMF, resulting in local flow that reduced dead zone area. The convection enhanced heat transfer within the melt, contributing to a more uniform temperature distribution. Experimental results indicated that PMF improved the α-Al phase in ZL205A aluminum alloy. Applying PMF treatment on the melt within the fabricated pouring cup largely refined the grain size of aluminum alloy and enhanced its mechanical properties. The tensile strength, elongation, and hardness of ZL205A heat-treated castings increased by 48.31, 185.71, and 7.76 pct, respectively.