基于离散元的颗粒性质标定及铺砂过程模拟  

Calibration of particle properties and numerical simulation of sand-laying process based on discrete element

作　　者：代福增 杨伟东[2] 王杞月 线洪萱 王媛媛[2] DAI Fuzeng;YANG Weidong;WANG Qiyue;XIAN Hongxuan;WANG Yuanyuan(School of Mechanical and Electrical Engineering,Zhongjie Vocational-technical School,Cangzhou,Hebei 061108,China;School of Mechanical Engineering,Hebei University of Technology,Tianjin 300401,China;Arizona College of Technology,Hebei University of Technology,Tianjin 300401,China)

机构地区：[1]中捷职业技术学校机电工程学院,河北沧州061108 [2]河北工业大学机械工程学院,天津300401 [3]河北工业大学亚利桑那工业学院,天津300401

出　　处：《河北工业大学学报》2024年第2期22-29,共8页Journal of Hebei University of Technology

基　　金：河北省科技重大专项资助项目(21284901Z)。

摘　　要：喷墨打印中,砂床质量的高低直接影响最终打印零件的质量,在砂层铺设过程中砂粒的颗粒性质是影响砂床质量的关键因素之一。为研究喷墨打印中颗粒性质对砂床质量的影响,以原砂为研究对象,通过实验和离散元仿真相结合的方法完成了砂粒间接触参数进行标定,并对覆膜砂接触参数进行研究,使用颗粒间的表面能来描述砂粒流动性的变化,通过实验与仿真结合的方法得到了催化剂含量和表面能之间的关系。在砂粒颗粒性质确定的基础上,构建了喷墨打印工艺中砂床铺设过程的离散元模型,完成了颗粒性质对铺砂质量影响的仿真实验,结果表明:催化剂含量的增加会降低砂床质量,但过低的催化剂含量会导致制件的尺寸精度和力学强度变差。因此,为了平衡固化效率和砂床质量,可将催化剂含量控制在0.4%到0.6%之间;在层厚和落砂质量一定的条件下,粒径系数是影响砂床质量的主要参数,粒径系数的减小会导致砂床质量的下降。In binder jetting 3D printing,the quality of the sand bed directly affects the quality of the final printed parts.The particle nature of the sand particles during the laying of the sand layer is one of the key factors affecting the quality of the sand bed.In order to study the effect of particle properties on the quality of sand bed in inkjet printing,raw sand was used as the research object,and the contact parameters between sand particles were calibrated through a combina⁃tion of experiment and discrete element simulation,and the contact parameters of coated sand were studied,use the sur⁃face energy between particles to describe the change of sand particle fluidity,and get the relationship between catalyst content and surface energy through a combination of experiment and simulation.Based on the determination of the prop⁃erties of the sand particles,a discrete element model of the sand bed laying process in the inkjet printing process was constructed,and the simulation experiment of the impact of particle properties on the sand laying quality was completed.The results show that the increase in the catalyst content will reduce the sand bed quality,but too low catalyst content will result in poor dimensional accuracy and mechanical strength of the parts.Therefore,in order to balance the solidifi⁃cation efficiency and the quality of the sand bed,the catalyst content can be controlled between 0.4%and 0.6%;under the condition of a certain layer thickness and falling sand quality,the particle size coefficient is the main parameter that affects the quality of the sand bed.The decrease of the diameter coefficient will lead to the deterioration of the quality of the sand bed.

关 键 词：喷墨打印 离散元 铺砂工艺 砂床质量 颗粒性质 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术]