压铸件铸造缺陷的计算机模拟与预测研究

压铸件铸造缺陷的分析及预测研究对保证压铸质量具有非常重要的意义。针对复杂、小型、薄壁压铸件的收缩缺陷，综合考虑了压铸件形状及其凝固过程中温度变化对缩孔缩松及气孔发生的影响机理，在其凝固过程温度场数值模拟的基础上提出了一种新的压铸件缩孔缩松判据。应用该判据对压铸件收缩缺陷和气孔缺陷的发生及危险部位进行了模拟预测，并对模拟预测的结果进行了可视化显示。预测结果与压铸件缺陷实际发生情况一致。

Study on Computer Simulation and Forecast on Casting Defects for Die Casting

The computer simulation and forecast of die casting defects is an important and effective way to improve the quality of die casting. In this paper,we focus our study on a complex workpiece of die casting. At first, an algorithm of numerical simulation for the temperature field of die casting during the solidification process is presented.On the basis of temperature field numerical simulation results,a new method to forecast the casting defects such as shrinkage and gas hole is advanced.Some reasons,such as structure and temperature change are employed to analyse the formation of shrinkage ,dispersed shrinkage and gas hole.The algorithm to forecast these casting defects is presented.The forecasting results correctly anastomose the facts of die casting defects.Finally the visualization of the numerical computation is achieved to make the view of results simple and intuitive.