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得到了7A04 铝合金在矩形脉冲磁场下凝固冷却曲线及晶粒尺寸变化规律，结合有限元数值模拟方法分析熔体内部脉冲磁场分布情况，研究了脉冲磁场特性对晶粒细化效果的影响。结果表明：在矩形脉冲磁场作用下，7A04 铝合金凝固组织得到不同程度的均匀细化。在最佳脉冲参数：频率 20Hz，峰值电流 100A，电流占空比 20%处理后，铸锭中心处、1/2R 处、边处晶粒平均尺寸分别为 122.9μm、120.38μm、114.7μm，较未处理铸锭平均晶粒尺寸分别下降了 24.3%、15.3%、22.6%。此时矩形脉冲磁场在熔体内产生 7.01×104N/m3 的电磁力，单周期释放磁能 3862.62J/m3，形成了良好的凝固组织细化条件。
The cooling curve and grain size variation of 7A04 aluminum alloy under rectangular pulse magnetic field were obtained. The distribution of pulsed magnetic field inside the melt was analyzed by finite element numerical simulation. The effect of pulsed magnetic field on grain refinement was studied. The results show that the solidified microstructure of 7A04 aluminum alloy is refined to different degrees under the rectangular pulse magnetic field. The average grain sizes at the center and 1 / 2R of the ingot after the best pulse parameters: frequency 20Hz, peak current 100A and current duty cycle 20% were 122.9μm, 120.38μm and 114.7μm, respectively The average grain size of untreated ingots decreased by 24.3%, 15.3% and 22.6% respectively. At this point, the rectangular pulsed magnetic field generated in the melt 7.01 × 104N / m3 of electromagnetic force, single-cycle release of magnetic energy 3862.62J / m3, forming a good solidification microstructure refinement conditions.