Luo Jixiang Pan Libo Pang Xin. Effects of Extrusion Pressure on Crystal Growth Rate and Arm distance. [J]. Special Casting & Nonferrous Alloys (5):35-37(2002)
Luo Jixiang Pan Libo Pang Xin. Effects of Extrusion Pressure on Crystal Growth Rate and Arm distance. [J]. Special Casting & Nonferrous Alloys (5):35-37(2002)DOI:
Effects of Extrusion Pressure on Crystal Growth Rate and Arm distance
摘要
研究了挤压铸造时挤压力对宏观晶体生长速度的影响
给出了晶体生长速度表达式。结果表明 :挤压力对合金宏观晶体生长速度的影响除与合金成分有关外
在某些挤压条件下
当形核率的增加幅度超过长大速度时
则挤压力可使宏观晶粒细化 ;反之
会使宏观晶粒变粗。随着挤压力的提高
合金凝固速度加快
一次枝晶间距和二次枝晶间距都随之减小
从而细化了树枝晶
Abstract
Effects of extrusion pressure on the growth rate of macro\|crystal in extruded casting were investigated.The mathematical expression for the growth rate of crystal was developed.It is found that besides the alloy composition
under some particular extruded conditions
the extrusion pressure resulted in refining macro\|grain when increase in nucleation rate exceeds growth rate and vice versa.The refined dendrite is responsible for the decrease in distance between both of the first dendrite and secondary dendrite during quickening alloy solidified rate with the increase of the extrusion pressure.