亚共晶铸铁一次结晶过程的两区域结晶物理模型

针对小于临界壁厚铸件的凝固过程建立了 1种新的两区域结晶模型 ;这种两区域模型与三区域模型结晶模型的区别在于 :在铸件的一次结晶过程中 ,铸件断面上不同时出现固相、固 液相、液相三区域共存的状态。这种模型的提出是对 1次结晶模型的补充和完善 ;它有利于揭示一次结晶的微观机理 ,得到铸铁的组织与机械性能的关系 ,从而为计算机仿真铸造合金的性能打下了良好的基础。

Two-region Crystal Microphysical Model on Primary Crystals of Hypoeutectic Cast

A new two-region crystal microphysical model, whose thickness is less than critical value, is established. This model is distinguished from the three-region crystal model in the process of primary crystals, in which not all exiting solid,liquid-solid, and solid at the same time on sections of casting. This model supplements the traditional crystal model. We know the whole micromechanism of primary crystal sand provided the relations between the structure of casting and the mechanism properties, as well as the result of good foundation for simulating mechanical properties of cast alloy.