基于离散元方法的型砂流动性仿真研究  

Simulation of Self-hardening Resin Sand Mobility Based on DEM

作　　者：张帅[1,2] 单忠德[1] 张杰[2] 

机构地区：[1]机械科学研究总院先进成形技术与装备国家重点实验室,北京100044 [2]北京科技大学机械工程学院,北京100083

出　　处：《铸造技术》2016年第2期288-291,共4页Foundry Technology

基　　金：机械科学研究总院技术发展基金资助项目

摘　　要：铸造用型砂预固化阶段的流动性是影响砂型固化后均实性的决定性因素。为了准确预测型砂预固化阶段的流动性,用型砂休止角表示其流动性,并提出一种基于DEM中JKR模型的方法准确仿真型砂休止角。通过建立JKR物理模型对原砂、碱性酚醛树脂和固化剂不同质量配比型砂的预固化阶段休止角进行仿真实验,并运用EDEM软件Protractor功能测得休止角数值,与试验休止角平均值相比误差在3%范围内。研究结果表明:基于DEM的JKR模型能够准确预测型砂预固化阶段的流动性,仿真结果为砂型数字化柔性挤压成形技术中型砂填充砂箱和砂型3D打印的工艺设计提供依据,对准确预测型砂成形能力和砂型固化后的紧实均匀度有重要意义。Mobility of molding sand in pre-solidifying stage is the determining factor of uniformity for sand mold. To predict the mobility of molding sand in pre-solidifying stage accurately, its repose angles, which represent the mobility of molding sand in pre-solidifying stage, were simulated based on discrete element method. The JKR model of molding sand in pre-solidifying stage with certain mass ratio was establisl]ed to analyze the contact force among molding sand particles. And their contour angles were measured by protractor function of EDEM. Simulation results show that the errors between average repose angles and experimental ones are less than 3%. Therefore, the repose angles represented the mobility of molding sand in pre-solidifying stage can be simulated by JKR model. And the simulation results are useful in designing processes of molding sand filling sand-box in sand digital flexible extrusion technology and sand mold 3D printing.

关 键 词：型砂 流动性 休止角 离散元方法 JKR物理模型 

分 类 号：TG221[金属学及工艺—铸造]