【摘要】 柱状晶向等轴晶转变(CET)是在一定的凝固过程中必须控制的一种显微组织转变。本文针对铝合金连铸坯凝固过程中柱状晶向等轴晶的转变,综合运用了正交试验研究、数值模拟计算、数学拟合等方法,分析了连铸过程主要工艺因素拉坯速度、一冷水量、二冷水量和浇注温度对连铸坯凝固过程中柱状晶向等轴晶转变位置的影响,提出了柱状晶向等轴晶转变的转变位置判据,即当连铸坯某一位置处的固相率等于0.3时,温度梯度G与冷却速度R 满足函数关系G0.8072/R=0.469时,在该位置处将发生柱状晶向等轴晶的转变。更多还原

【Abstract】 The columnar to equiaxed transition （CET） is a kind of microstructural transformation in certain solidification, which should be controlled. Combining the methods of the orthogonal experimental analysis,numerical simulation and curve fit, the influence of the technical parameter of continuous casting on the CET position of billet has been analyzed and a criterion is put forward as follows:G^0.8072/R=0.469 when the fraction of solid is equal to 0.3, where G and R represent temperature gradient and cooling rate respectively.更多还原