锌锭模热力行为数值模拟及失效分析  

Thermal force behavior numerical simulation and failure analysis of zinc ingot die

作　　者：杨远平[1,2] 严宏志[1] 

机构地区：[1]中南大学机电工程学院,湖南长沙410083 [2]湘西民族职业技术学院机电系,湖南吉首416000

出　　处：《中南大学学报（自然科学版）》2011年第5期1310-1315,共6页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(50975291)

摘　　要：针对锌锭模在使用过程中内圆角部位因疲劳裂纹而失效的问题,利用有限元方法,模拟锌液浇注及其凝固过程中锌锭模的温度场和应力场,找到锌锭模上拉应力最大的3个点,此3点即为控制模具使用寿命的关键点。分析锌锭模的初始温度、锌液的浇注温度对关键点最大应力的影响,模拟锌锭模自身铸造应力和组织性能,得到模具断面铸造应力和抗拉强度分布。分析锌锭模裂纹产生的原因,提出锌锭模使用工艺。研究结果表明:热冲击和疲劳是锌锭模产生裂纹的主要原因,裂纹不一定位于应力最大部位,而是位于应力较大且组织性能较差的部位;在锌锭浇注过程中,当模具的温度较低时,应采用低温浇注。Aiming at breakage of zinc ingot die caused by fatigue crackle in the process of using at comer, the temperature and stress field of zinc ingot die in the process of zinc melt casting and solidification were simulated using FEM. Three maximum stress nodes in zinc ingot die were found, which are the key nodes that decide the using life of die. The influences of die initial temperature and zinc melt casting temperature on key nodes maximum stress were analyzed. By the simulation of casting stress and structure property for zinc ingot die, the distributions of casting stress and tensile strength in flange section were obtained. The crackle reasons of zinc ingot die were analyzed. The application technology for zinc ingot die was proposed. The results show that the primary reasons caused crackle are heat shock and fatigue, and the crackle is not necessarily at the maximum stress position where the stress is comparatively large and the structure property is worse. In the process of zinc ingot casting, when the temperature of die is lower, the casting temperature of zinc melt should be lower, too.

关 键 词：锌锭模 热力行为 数值模拟 失效分析 

分 类 号：TG213[金属学及工艺—铸造]