电脉冲处理时间对Al-18%Si合金凝固组织的影响

Effect of Electric Pulse Treating Time on Solidification Structure of A1-18%Si Alloy

研究了A1-18%Si合金液在较高过热度时,连续电脉冲作用下凝固组织的变化规律。结果表明,A1-18%Si过共晶合金凝固组织以初晶硅数量为标志,经电脉冲处理后呈周期性变化,变化的特征时间约为120s。初晶硅数量较多时,共晶相较少;初晶硅数量较少时,出现大面积的共晶区,同时初晶硅局部偏聚。分析表明,电脉冲处理首先对A l-Si熔体的液态结构产生影响,从而使其凝固后的组织发生改变。

The effect of the continue electric pulse process on the solidification structure of superheated liquid Al-18% Si alloy was studied. The results show that the quality of primary silicon is the mark of the periodical change of solidification structure and the periodical time is about 120s. The amount of eutectic phase decreases when the content of primary silicon increases, the large area of eutectic phase appears and the other part is primary silicon when its content reduces. Theoretical analysis shows that the electric pulse process has influence on the structure of liquid metal, leading to the solidification structure modified.