Materials Science and Engineering A 407 (2005) 11–23 Automatic voxel-based generation of 3D microstructural FE models and its application to the damage analysis of composites Leon L. Mishnaevsky Jr. a,b,∗ a University of Stuttgart, IMWF, Pfaffenwaldring 32, 70569 Stuttgart, Germany b Technical University of Darmstadt, Institute of Mechanics, Germany Accepted 28 June 2005 Abstract A method and a program for the automatic reconstruction and generation of 3D microstructures of composites on the basis of voxel array data have been developed and tested. Different methods of reconstruction and generation of finite element models of 3D microstructures of composite materials (geometry-based and voxel array based) are discussed and compared. With the use of the developed program, the deformation and damage evolution in composites with random and graded microstructures were numerically simulated. The tensile stress–strain curves, fraction of failed elements, and stress, strain and damage distributions at different stages of loading were determined for different random microstructures of the composites. It was shown that the stiffness, peak and yield stresses of a graded composite decrease with increasing the sharpness of the transition zone between the region of high volume content of the hard phase and the reinforcement free region. The critical applied strain, at which the intensive damage growth begins, is decreasing with increasing the volume content of the hard phase of the composite. © 2005 Elsevier B.V. All rights reserved. Keywords: 3D microstructural FE models; Damage analysis; Composites 1. Introduction Computational analysis of the microstructure–strength interrelations of composite materials can serve as a basis for the optimization of their properties. The development of methods of the automatic generation of numerical models of composites, which take into account 3D complex microstruc- tures of the materials, can be of great importance for the computational testing of materials and for the determination of optimum microstructures. The purpose of this work was to develop and to test numer- ical tools for the automatic development of finite element models of complex 3D microstructures of composites, and to apply the numerical tools to the analysis of the effect of ran- dom (including percolating) microstructures of metal matrix composites on the deformation and damage resistance of the composites. ∗ Tel.: +49 711 6853049; fax: +49 711 6852635. E-mail address: mishnaevsky@web.de. A new program was developed for the automated gen- eration of three-dimensional microstructural FE models of composite materials with complex microstructures. The pro- gram (called “Voxel2FEM”) allows to reconstruct complex 3D microstructures of materials on the basis of the voxel array data. The developed method and program were applied for the numerical analysis of strength, deformation and dam- age growth in the materials with random, percolating and near-percolating microstructures (i.e., where inclusions form a skeleton, or connected clusters). This group of materials includes, for instance, biomate- rials, tool materials (e.g., WC/Co cemented carbides with high content of WC, in which the WC skeleton ensures high hardness) [1–3], sintered Al/SiC composites [4], Ag/Ni com- posite materials, polymer composites, containing conducting filler particles (e.g., graphite) as well as other dielectric com- posites. Some graded composite materials have regions with interpercolating phases between the regions of high concen- tration of each phase [5]. Furthermore, the group of materials, for which the analysis in this work can be relevant, includes 0921-5093/$ – see front matter © 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.msea.2005.06.047