双辊连续铸轧纯铝薄带凝固微观组织模拟及验证

Validation and Simulation for Solidification Process of Twin-Roll Continuous Casting Aluminum Thin Strip

以双辊连续铸轧薄带工艺凝固过程为基础,同时基于金属凝固的基本原理建立了双辊连铸薄带凝固过程的异质形核模型、修正的枝晶尖端生长动力学模型、柱状晶向等轴晶转变(CET)的解析模型以及基于元胞自动机(CA)的双辊连续铸轧薄带凝固组织演变的仿真模型。数值模拟结果表明,所建立的数学模型能够合理描述晶粒沿任意角度生长的过程,温度场、溶质场和微观组织形貌的模拟计算结果合理,同时利用双辊薄带连续铸轧工业纯铝凝固过程验证了数学模拟的可行性。

Based on the solidification of twin-roll continuous casting thin strip, the analytical model of heterogeneous nucleation, the a- mended growth of tip and columnar dendrity transformation to equiaxis dendrity （CET） of twin-roll continuous casting thin strip solidification are established by means of the principle of metal solidification and based on the cellular automaton, the emulational model of twin-roll continuous casting thin strip solidification is established. Simulated results showed that the grain growth in random preferential growth directions can be described by the model reasonably, and the simulated results were coincident with actual phenomena. Mean- while has confirmed the mathematical simulation feasibility by using the solidification process of twin-roll continuous casting aluminum thin strip.