摘要
为了预测粘结剂喷射增材制造(BJAM)金属坯件烧结过程中的收缩和变形,建立了一种基于黏弹性计算的高温蠕变模型,用于模拟烧结过程中的热诱导蠕变行为。该模型在烧结的微观和宏观描述之间建立了联系,考虑了晶界扩散、重力作用、晶粒生长及热膨胀对烧结收缩和变形的影响。模型中的参数依赖于粒径、相对密度和温度。通过在Abaqus中编写用户自定义子程序CREEP来实现数值模拟,并选用广泛应用于工业的316L粉末进行实验验证。结果显示,x、y方向的平均线性收缩率为11.61%,而z方向的平均线性收缩率为12.64%,相较于实验值(x向平均线性收缩率为10.12%,y向平均线性收缩率为10.15%,z向平均线性收缩率为11.21%),误差范围为1%~2%,表明该模型具有较好的预测效果,特别是对于以晶界扩散为主要烧结机制的316L不锈钢零件。优化和获取更精确的材料性能参数,特别是高温条件下的,将有助于进一步提高模型的预测精度。
In order to predict the shrinkage and deformation during the sintering process of metal green parts fabricated by binder jetting additive manufacturing(BJAM),a high-temperature creep model based on viscoelastic calculation was established to simulate the thermally induced creep behavior during the sintering process.This model establishes a connection between the microscopic and macroscopic descriptions of sintering,taking into account the effects of grain boundary diffusion,the action of gravity,grain growth,and thermal expansion on the sintering shrinkage and deformation.The parameters in the model depend on the particle size,relative density,and temperature.The numerical simulation was implemented by writing a user-defined subroutine CREEP in Abaqus,and the 316L powder widely used in industry was selected for experimental verification.The results show that the average linear shrinkage rates in the x and y directions are 11.61%,while the average linear shrinkage rate in the z direction is 12.64%.Compared with the experimental values(the average linear shrinkage rate in the x direction is 10.12%,the average linear shrinkage rate in the y direction is 10.15%,and the average linear shrinkage rate in the z direction is 11.21%),the error range is approximately 1%to 2%.This indicates that the model has a good predictive effect,especially for 316L stainless steel parts in which grain boundary diffusion is the main sintering mechanism.Optimizing and obtaining more accurate material property parameters,especially under high-temperature conditions,will help to further improve the prediction accuracy of the model.
作者
李伟
黄延禄
嵇海涛
徐雨欣
王天宇
杨永强
LI Wei;HUANG Yanlu;JI Haitao;XU Yuxin;WANG Tianyu;YANG Yongqiang(School of Mechanical and Automotive Engineering,South China University of Technology,Guangzhou 510641,China)
出处
《粉末冶金工业》
北大核心
2025年第2期22-30,共9页
Powder Metallurgy Industry
基金
广东省重点领域研发计划资助项目(2018B090905002)
关键词
粘结剂喷射
固相烧结
变形
收缩
数值模拟
binder jetting
solid-state sintering
deformation
shrinkage
numerical simulation
作者简介
李伟(1998-),男,硕士,主要研究方向为增材制造;通信作者:黄延禄(1972-),男,博士,副教授,主要研究方向为增材制造。
