Modelling of metal foams by a modified elastic law
Modelling of metal foams by a modified elastic law
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DOI：
10.1016/j.mechmat.2016.07.007
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发表时间：
2016-10-01
影响因子：
3.9
通讯作者：
Diebels, S.
中科院分区：
文献类型：
--
作者：
Jung, A.;Diebels, S.
泡沫金属是一种具有生物启发性的微异质材料，在轻质结构或动能吸收方面具有巨大的应用潜力。基于其复杂的微观结构，整体性能强烈地依赖于微观结构的局部性能。根据泡沫金属的可压缩特性，在具有几个孔的厚度的破碎区中存在局部损伤。规模效应非常重要。应变局部化和损伤局部化的变形带的建立导致宏观应力-应变曲线中的应力波动，在这方面的贡献，从一个简化的微观结构的动机的一维流变模型，RVE为基础的连续模型，它允许明确考虑尺寸效应，开发的宏观尺度上的投影的微观应力。为了简化，使用RVE的单孔隙模型。分析了不同类型的单孔函数和离散化。在第二步中，将结果与具有不同数量的孔的完全解析的微观模型进行比较，以找到RVE的正确尺寸。(C)2016爱思唯尔有限公司版权所有
Metal foams are bio-inspired microheterogeneous materials with great potential for application in lightweight construction or as kinetic energy absorbers. Based on their complex microstructure, the global properties depend strongly on the local properties of the microstructure. According to the compressible behaviour of metal foams, there is a localised damage in crushing zones with a thickness of several pores. Size effects are very important. The built-up of deformation bands with strain localisation and damage localisation causes stress-fluctuations in the macroscopic stress-strain curve.In this contribution, starting from a simplified microstructural motivated 1D rheological model, a RVE-based continuum model, which allows the explicit consideration of size effects, is developed by the projection of microstresses on the macroscale. For simplification, a one-pore model for the RVE is used. Different types of one-pore functions and discretisations were analysed. In a second step, the results are compared with fully resolved micromodels with different number of pores in order to find the right size for the RVE. (C) 2016 Elsevier Ltd. All rights reserved.