摘要
为准确模拟选区激光烧结过程中的温度场,有效预测零件的热应力和变形,在经典Galerkin有限元法推导选区激光烧结过程的三维温度场计算模型基础上,提出了Galerkin Gradient Least-Squares(GGLS)稳定有限元法的三维温度场计算模型,分别采用两种方法模拟了激光烧结过程中的温度场分布。模拟结果表明:由于聚合物材料的导热系数较小,材料传热困难,在Galerkin法求解温度场过程中出现了明显的温度忽高忽低的数值振荡现象,应用GGLS法可以有效改善数值振荡,获得较为准确的模拟结果。激光扫描结束的地方温度最高,随着距离的增加,温度迅速降低。在零件上表面很薄的一层区域温度最高,沿烧结深度方向向内,温度逐渐降低。
To simulate the temperature field of selective laser sintering process correctly and predict the thermal stress and deformation of part effectively,based on the three-dimensional temperature field calculation model of selective laser sintering process derived by the classical Galerkin finite element method,the Galerkin gradient least-squares(GGLS)stabilized finite element method was proposed to build the calculation model of temperature field.The two methods were employed respectively to simulate the temperature field during selective laser sintering process.The simulation results show that due to the small thermal conductivity of the polymer material,the heat transfer of the material is difficult and the obvious numerical oscillation of temperature occurs in the process of solving the temperature field by Galerkin method.The GGLS method can effectively improve the numerical oscillation phenomenon and more accurate simulation results were obtained.The temperature is the highest where laser scanning ends,and decreases quickly as the distance increases.The highest temperature area appears in a thin layer on the upper surface of the part,and the temperature gradually decreases in the inward depth direction.
作者
孟娟
丁浩亮
温馨
蔡令令
严波
MENG Juan;DING Hao-liang;WEN Xin;CAI Ling-ling;YAN Bo(School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200030,China;Aerospace Research Institute of Materials&Processing Technology,Beijing 100076,China)
出处
《塑性工程学报》
CAS
CSCD
北大核心
2021年第1期98-105,共8页
Journal of Plasticity Engineering
基金
国家重点研发计划项目(2018YFB1106700)。
