热挤压模具热力耦合三维数值分析

来源期刊：中南大学学报(自然科学版)2004年第1期

论文作者：倪正顺 帅词俊 钟掘

文章页码：86 - 90

关键词：三维数值分析;热力耦合;热挤压模具;温度场;应力场

Key words：three-dimensional numerical analysis; thermal-mechanical coupling; hot extrusion die; temperature field; stress field

摘    要：根据热挤压模具的工作特点,基于热弹性力学和有限应变理论,建立了三维热力耦合弹塑性有限元方程。用该方程研究方管铝型材平面分流组合模的三维数值分析,在确定边界条件和计算挤压力的基础上,通过合理设计单元类型,计算了模具在挤压过程中的温度场和应力场。通过分析模具应力,发现在模桥与模芯相接处有较大的应力集中,与出现裂纹的位置相吻合,说明应力集中是模具桥裂的主要原因之一。

Abstract: According to the characteristics of hot extrusions, a three-dimensional coupled thermal-me-chanical finite element equation was set up based on the thermo-elasticity mechanism and finite strain theory in this paper. Based on the determining of boundary conditions and calculating the extrusion pressure, the temperature field and stress field during extrusion were calculated by applying the equation to the aluminum square profile hot extrusion porthole compound die and through the rationally designing element types. The results show that there exists a stress concentration at the junctions between the die core and the porthole bridge, which agrees quite well with the location of the porthole bridge crack. This indicates that the stress concentration is one of dominating factors causing porthole bridge cracks.