基于ABAQUS有限元片剂压缩过程应力分析

ABAQUS-based stress analysis during tablet compression

基于有限元分析软件ABAQUS对片剂压缩过程进行模拟和仿真分析。通过该软件来研究片剂内部应力的变化及分布情况,粉体在被压缩直到解压的过程,Mises等效应力由开始主要集中于模型边缘,尤其是靠近中模的区域,在被顶出阶段,则转变成靠近下冲的区域应力最大化。而粉体内部的剪切应力呈现正负数值,说明剪切应力的方向存在相反的情况。密度的主要分布还是以上下冲以及中模区域最为集中且较大,粉体与中模之间的摩擦系数越大,分布在上下冲和中模的应力应变就越大,密度稍微变小。由此可以得出,较为适当的摩擦系数才能够制得工艺合格的片剂,在大摩擦系数下制得的片剂则容易产生坏片、裂片、破碎等相关问题。

The finite element analysis software ABAQUS was used for analysis of stress distribution and variations in the tablets during compression.Mises equivalent stress concentrated mainly on the edge of the model （especially in the area near the middle model） when the power was compressed into a tablet,and in the ejection phase of the tablet,the maximal regional stress occurred near the undershoot.The shear stress in the powder showed both positive and negative values during compression,indicating the presence of shear stress in opposite directions.Density distribution analysis showed that high density was distributed mainly in the overshoot and undershoot areas and in the middle model.As the friction coefficient increased between the power and the middle model,the stress increased in the overshoot,undershoot and the middle model while the density decreased slightly.These results indicate that an appropriate friction coefficient is essential for the production of qualified tablets,and a large friction coefficient is liable to cause tablet damage and breakage and other quality issues.