金属粉末冲击压制过程中冲模质量及颗粒模型的优化分析

在模拟金属粉末冲击压制时,由于模型颗粒数与实际不同,仿真模型的准确度不高。本文引入模型冲模质量与实验冲模质量比值作为当量质量,研究了压制初始速度、横向与纵向颗粒数对当量质量的共同影响。采用ABAQUS软件建立了不同初始速度下的压制模型,利用1stOpt软件拟合出预估模型,通过ABAQUS仿真数据验证了预估模型,取得了当量质量与相对密度之间的关系,并且分别得到了横向与纵向两组模型的初始速度、颗粒数对冲模当量质量的影响关系。利用ABAQUS仿真数据得到的预估模型最终形式为:当冲模初始速度为20 m·s-1时,横向颗粒数为5、纵向颗粒数为6（H₅Z₆）的颗粒模型的当量质量为1.03,比经典9颗粒模型进行模拟更能接近实际的压制情形。

Optimization analysis of die mass and particle model in metal powder impact compaction

In the simulation of metal powder impact compaction, the simulation model is not accurate because of the particle number difference between the model and actuality. Therefore, the relative mass was introduced as the die mass ratio between the simulation and experiment, and the influences of initial pressing velocity and particle array in transverse and longitudinal direction on the relative mass were study in this paper. The ABAQUS software was used to establish the compaction model at different initial velocity. The prediction formula was fitted by 1stOpt software. Finally, the simulation model was used to verify the prediction formula, draw the relationship between the relative mass and relative density, and obtain the relationship between the initial velocity and particle array in transverse and longitudinal direction. In the result, the final formula is obtained by using ABAQUS simulation data. When the die velocity is 20 m·s-1, the relative mass in H₅Z₆ particle model (5 particles in transverse direction and 6 particles in longitudinal direction) is 1.03, which is closer to the actual pressing than that of the nine-particles model.