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进行了脉冲磁场下制备Al-20Si功能梯度材料的研究,分析了脉冲电压、脉冲频率、模具预热温度及浇注温度对初生Si形态和分布的影响.结果表明,利用脉冲磁场成功制备了Al-20Si功能梯度材料,初生Si聚集在试样边缘,心部基本无初生Si.在0～150 V范围内,随着脉冲电压的增加,初生Si形态由块状变成粗大的板条状,其平均分布宽度逐渐减小;在1～10 Hz范围内,随着脉冲频率增加,初生Si平均分布宽度逐渐减小;当浇注温度在690～780℃范围内或模具预热温度在400～700℃范围内变化时,随浇注温度或模具预热温度的升高,初生Si平均分布宽度先减小后有所增大.“,”Al-20Si functionally gradient materials under pulsed magnetic field was fabricted.Effects of pulse voltage,pulse frequency,mold temperature and pouring temperature on the morphology and distribution of primary silicon in the Al-20Si gradient alloy were investigated.The results reveal that Al-20Si functionally gradient material can be prepared successfully by pulsed magnetic field.Primary silicon is segregated in the edge,and it is absent in the center position.In the range of 0～150 V,with the increase of the pulse voltage,morphology of primary silicon is changed from small blocks to large lath shape,and the average distribution width is decreased gradually.In the range of 1～10 Hz,the average distribution width of primary silicon is decreased with the increase of pulse frequency.When the pouring temperature is at 690～780 ℃ or mold temperature is at 400～700 ℃,with the increase of pouring temperature or mold temperature,the average width of primary silicon is decreased at first and then increased.