Al-Cu共晶合金定向凝固不同抽拉速度下的组织演化

Effects of Different Pulling Velocity on Microstructure Evolution in Directionally Solidified Al-Cu Eutectic Alloy

研究了Al-Cu共晶合金定向凝固下的组织演化规律。结果表明,在一定的温度梯度下,随着凝固速度的增加,共晶层片间距因Al2Cu分叉而发生细化。在定向凝固过程中,层片间距的调整是通过纵向生长上的分叉和横向上的错配边界移动实现的,共晶组织达到稳态的过程是纵向和横向不断调整的过程。

Microstructure evolution of Al-Cu eutectic alloy in directional solidification was observed. The results reveal that at a given temperature gradient,with increasing in pulling velocity,eutectic lamellar spacing is decreased as a result of bifurcation of Al2Cu phase. During directional solidification process,adjustment of eutectic lamellar spacing is realized through bifurcation in longitudinal growth and mismatched boundary movement in the horizontal direction,and eutectic microstructure tends toward stable through continuous adjustment in longitudinal and horizontal directions.