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研究了不同脉冲电压和脉冲频率对Al-20Si合金中初生Si分布和形态的影响。结果表明,在脉冲磁场的作用下,初生Si主要表现为偏聚和粗化,为梯度材料的制备提供了可能;当脉冲电压为80V时,初生Si有所粗化且偏聚,其大量集中在边部,心部几乎不含初生Si;当脉冲电压为160V时,初生Si进一步粗化且有所团聚,但整体上分布趋于均匀化;当脉冲电压增加至240V时,初生Si团聚和粗化现象有所减弱,且其分布也较均匀。当脉冲频率变化较小时(1~5Hz),初生Si的分布和形态不会随脉冲频率的增加而改变;当脉冲频率增加到10Hz时,初生Si出现了偏聚和粗化的现象。
The effects of pulse voltage and pulse frequency on the distribution and morphology of primary Si in Al-20Si alloy were investigated. The results show that primary Si is mainly segregation and coarsening under the action of pulsed magnetic field, which makes it possible to prepare gradient materials. When the pulse voltage is 80V, the primary Si is roughened and segregated, When the pulse voltage is 160V, the primary Si further coarsens and agglomerates but the distribution tends to be uniform. When the pulse voltage is increased to 240V, the primary Si agglomerates and Coarsening phenomenon has weakened, and its distribution is more uniform. When the pulse frequency changes slightly (1 ~ 5Hz), the distribution and morphology of primary Si does not change with the increase of pulse frequency. When the pulse frequency increases to 10Hz, primary Si appears segregation and coarsening phenomenon.