【摘要】 研究了固液两相区等温处理对铸态ZA2 7合金初生相形貌的影响。结果表明 :在固液两相区进行等温处理时 ,枝晶熔断受固液界面处原子的扩散控制 ,提高等温温度、延长等温时间因有利于Zn和Al原子的扩散而促进初生相由枝晶向颗粒状晶演变 ;预变形促进初生相形貌演变的根本原因在于等温处理时液相沿预变形产生的亚晶界的熔渗。更多还原

【Abstract】 The effects on transformation of primary phase morphology were studied by using isothermal heat treatment of the as cast ZA27 ingots in semi solid state. The results show that remelting of dendrite is controlled by atom diffusion in the solid liquid interface. Increasing isothermal temperature and prolonging isothermal time, which promoted the diffusion of Zn and Al atoms, are helpful to the transformation. Liquefaction along hypo grain boundaries caused by pre deforming is the radical reason for the morphological transformation. [更多还原