型砂压实过程的非线性有限元数值模拟

The Nonlinear Finite element Numerical Simulation in the Compacting Process of Molding Sand

在粘土砂湿型铸造生产的造型方法中,型砂压实过程是型砂最终紧实的主要途径。在射压造型、静压造型等主要的现代造型方法中型砂紧实都采用了压实。对压实过程进行数值模拟,可以预测型砂紧实分布情况,为优化压实工艺和提高铸型质量提供依据。但是粘土砂湿型造型的紧实过程是涉及离散材料体系以及材料非线性、几何非线性、接触非线性等问题共存的一个复杂的力学过程,因此对造型紧实过程进行数值模拟具有相当难度,常用软件如ANSYS、ABAQUS等无法直接对紧实过程进行模拟分析。本文在商用ANSYS软件中采用APDL语言二次开发编程的方法,编写了相应的计算程序并耦合到ANSYS中对型砂压实过程进行了数值模拟,取得了较好的效果。

Among the ways of molding process in modern green sand casting production, the compacting process of molding sand is one of the main processes in making high density mold, which is widely used in many modern molding process such as injection molding, airflow squeeze molding and so on. The numerical simulation on compacting process can help to predict the density distribution of green sand mold and to optimize the compacting process in order to improve the quality of sand mold. It is quite difficult to simulate the compacting process directly with commercialized software such as ANSYS and ABAQUS because the compacting process is a complicated mechanical process which involves material nonlinearity, geometrical nonlinearity and contact nonlinearity problems at the same time. In this article, the related module of ANSYS was reprogramed with APDL language and the compacting process of green sand was successfully simulated. Furthermore the satisfactory result was obtained.