Optimization of the mechanical properties of virtual porous solids using a hybrid approach

A hybrid strategy based on artificial neural network/genetic algorithms is suggested to optimize the mechanical properties of cellular solids. Three-dimensional void structures are generated using a random sequential addition algorithm in which spherical void particles are positioned in a solid phase matrix with a control of their size distribution and overlapping. This allows us to create an open-cell structure with relative densities in the range 0.1–0.3. Finite element calculation is used to assess the effective Young’s modulus as a function of generation parameters. Relative Young’s moduli in the three main directions of the solid are isotropic with respect to the generation algorithm constraints and adhere qualitatively to the common theory on effective properties of open-cell structures. Moreover, the effective response is found to be correlated to the randomness of the void structure, which exhibits, in some cases, an ordered cell configuration. In order to quantitatively describe these correlations and to check the sensitivity of the mechanical response to the structural features in addition to sampling and discretization levels, the hybrid strategy described above is considered. The main motivation was to decrease the finite element simulation time by predicting, where possible, the correlations instead of calculating them. In addition, the use of the hybrid strategy informs about the optimal mesh with respect to the generation variables. This strategy proved to be an efficient technique in enhancing the predictions and complementary to the finite element methodology.

[1]  Hilary Bart-Smith,et al.  Compressive deformation and yielding mechanisms in cellular Al alloys determined using X-ray tomography and surface strain mapping , 1998 .

[2]  Pierre M. Adler,et al.  The effective mechanical properties of random porous media , 1996 .

[3]  M. Scanlon,et al.  Compressive elastic modulus and its relationship to the structure of a hydrated starch foam , 2003 .

[4]  Matthew J. Silva,et al.  The effects of non-periodic microstructure on the elastic properties of two-dimensional cellular solids , 1995 .

[5]  R. Dendievel,et al.  Relating cellular structure of open solid food foams to their Young’s modulus: Finite element calculation , 2008 .

[6]  L. Salvo,et al.  Mechanical properties of bread crumbs from tomography based Finite Element simulations , 2005 .

[7]  Ghislain Montavon,et al.  Artificial intelligence implementation in the APS process diagnostic , 2004 .

[8]  Comparing Heuristic and Deterministic Approaches to Optimise Mechanical Parameters of Biopolymer Composite Materials , 2009 .

[9]  Norman A. Fleck,et al.  Effect of imperfections on the yielding of two-dimensional foams , 1999 .

[10]  Joachim L. Grenestedt,et al.  Influence of wavy imperfections in cell walls on elastic stiffness of cellular solids , 1998 .

[11]  David E. Goldberg,et al.  Genetic Algorithms in Search Optimization and Machine Learning , 1988 .

[12]  Ghislain Montavon,et al.  Modeling of the APS plasma spray process using artificial neural networks: basis, requirements and an example , 2004 .

[13]  S. Guessasma Young’s modulus of 2D cellular structures under periodic boundary conditions and subject to structural effects , 2008 .

[14]  J. Sherwood,et al.  LETTER TO THE EDITOR: Packing of spheroids in three-dimensional space by random sequential addition , 1997 .

[15]  Hilary Bart-Smith,et al.  Experimental analysis of deformation mechanisms in a closed-cell aluminum alloy foam , 2000 .

[16]  Michael F. Ashby,et al.  Multifunctionality of cellular metal systems , 1998 .

[17]  P. Cloetens,et al.  X-ray tomography applied to the characterization of cellular materials. Related finite element modeling problems , 2003 .

[18]  S. Guessasma,et al.  On the implementation of the fractal concept to quantify thermal spray deposit surface characteristics , 2003 .

[19]  Paolo Colombo,et al.  Cellular Ceramics: Structure, Manufacturing, Properties and Applications , 2005 .

[20]  U. Ramamurty,et al.  Tensile strength of a closed-cell Al foam in the presence of notches and holes , 1999 .

[21]  W. T. Illingworth,et al.  Practical guide to neural nets , 1991 .

[22]  Edward J. Garboczi,et al.  Elastic properties of model random three-dimensional open-cell solids , 2002 .

[23]  David Bassir,et al.  Identification of a spatial linear model based on earthquake-induced data and genetic algorithm with parallel selection , 2007 .

[24]  L. Gibson,et al.  Uniaxial strength asymmetry in cellular materials: An analytical model , 1998 .

[25]  David Bassir,et al.  Hybrid computational strategy based on ANN and GAPS : Application for identification of a non-linear model of composite material , 2009 .

[26]  John Banhart,et al.  A study of aluminium foam formation—kinetics and microstructure , 2000 .

[27]  Kalyanmoy Deb,et al.  Current trends in evolutionary multi-objective optimization , 2007 .

[28]  J. Banhart,et al.  Deformation characteristics of metal foams , 1998 .

[29]  Gerald T. Seidler,et al.  Simulation of the densification of real open-celled foam microstructures , 2005 .

[30]  N. Langrana,et al.  Effects of morphology and orientation on the behavior of two-dimensional hexagonal foams and application in a re-entrant foam anchor model , 1998 .

[31]  Debes Bhattacharyya,et al.  Handbook of Engineering Biopolymers : Homopolymers, Blends and Composites , 2007 .

[32]  John H. Holland,et al.  Adaptation in Natural and Artificial Systems: An Introductory Analysis with Applications to Biology, Control, and Artificial Intelligence , 1992 .

[33]  David Bassir,et al.  Multiobjective stacking sequence optimization for laminated composite structures , 2009 .

[34]  Lorna J. Gibson,et al.  Effects of solid distribution on the stiffness and strength of metallic foams , 1998 .

[35]  Salvatore Torquato,et al.  Effective mechanical and transport properties of cellular solids , 1998 .