铝锰黄铜中铁的宏观偏析的形成与防止

Forming and Preventing of Iron Macrosegregation for Al-Mn Brass

在实验研究了铝锰黄铜中初生富铁相的上浮条件与铁在铸件内的分布规律、偏析量与防止方法。实验结果与螺旋桨内偏析作了对比,指出铸件内铁倾向在后凝区富集,仅在不存在对流条件下,铁的上浮才会产生,提出对流驱动机构来解释铸件内铁的宏观偏析的形成。

The conditions of floating off of iron-rich phase for Al-Mn brass, the distribution of iron in castings, the iron segregation and its prevention have been investigated in laboratory.The experimental results have been compared with the segregation in large propeller castings. The conclusions are that the iron-rich phase prefer to build up in the final solidified zone of castings, and there is a tendency to float off of iron-rich phase if the liquid alloys are kept quietly in a constant temperature that iron-rich phase has crystallized. A convection model has been taken to explain the formation of iron macrosegregation in castings.