Influences of different pulse voltage

pouring temperature and mold temperature on the solidified structure of 7075aluminum alloy under pulsed magnetic field were investigated

and the related mechanism was also described.The results show that solidification structure of 7075alloy can be refined obviously under the pulsed magnetic field.The primary phase of the 7075alloy is transformed from developed dendrites into rossette-like or spherical crystals.With pulse voltage increasing from 0to 210V

pouring temperature decreasing from 730 ℃to 640 ℃ or mold temperature decreasing from 600 ℃to room temperature

the average grain size of the alloy is decreased.When pulse voltage is 210V

the average grain size of the alloy reaches 252μm.With pouring temperature or mold temperature increases

primary grain in the alloy becomes spherical structure increasingly.The grain refinement mechanism of the alloy is characterized by electromagnetic stirring and electromagnetic oscillation under the pulsed magnetic field.