7050铝合金大铸锭半连续铸造过程数值模拟  

Modeling of Semi-continuous Casting Process for 7050 Aluminum Alloy Ingot

作　　者：马维策[1] 胡士成[1] 杨运猛[1] 付明志[1] 胡永清[1] 

机构地区：[1]中南大学机电工程学院

出　　处：《特种铸造及有色合金》2008年第2期112-115,共4页Special Casting & Nonferrous Alloys

基　　金：国家重点基础研究发展计划(973计划)资助项目(2005CB23707)

摘　　要：利用大型有限元软件MSC.marc,建立了7050铝合金大铸锭的半连续铸造热-力耦合有限元模型,模型采用8节点六面体单元,考虑了凝固时的液-固相变以及凝固潜热的影响,定义了半连铸过程复杂的边界条件,分析了不同的铸造速度对温度场、应力场的影响规律。计算结果显示,降低铸造速度,可以减小铸锭内层和外层冷却速度的差别,降低铸锭表层拉应力,有利于促进铸锭的成形,减小产生裂纹的倾向性。The tendency and direction of crack formation in the round ingot is closely dependent on the casting speed in semi-continuous casting.The coupled thermal-stress finite element model for semi-continuous casting 7050 aluminum alloy billets has been established based on MSC.marc software,in which the hexahedral element type with eight nodes is adopted and the influence of liquid-solid transformation and solidification latent heat are considered.The effects of different casting speeds on temperature field and stress field in semi-continuous casting have been simulated with determining the complicated boundary confined condition.The simulated results indicate that the decrease of casting speed can reduce the gradient of cooling rate between inner and outer of the ingot to decrease the tensile stress in ingot surface,which is helpful for promoting the formation of the ingot and relieving the tendency of crack formation.

关 键 词：7050铝合金 半连续铸造 圆锭 热裂 数值模拟 

分 类 号：TG249.7[金属学及工艺—铸造]