T.Y. Wu¹, W.C. Tsai², J.J. Lee²

CMC-Computers, Materials & Continua, Vol.17, No.3, pp. 175-214, 2010, DOI:10.3970/cmc.2010.017.175

Abstract The crushing of cellular materials is a highly nonlinear problem, for which geometrical, material, and contact/impact must be treated in one analysis. In order to develop a framework able to solve it efficiently and accurately, in this paper procedures for in-plane crushing analysis of cellular materials using vector form intrinsic finite element (VFIFE) is performed. A beam element of VFIFE is employed to handle large rotation and large deflection in the cell walls. An elastic-plastic material model with mixed hardening rule is adopted to account for material nonlinearity. In addition, an efficient contact/impact algorithm is designed to treat the complex… More >

Surya R. Kalidindi^1,2,3, Stephen R. Niezgoda¹, Giacomo L,i^1,1, Tony Fast¹

CMC-Computers, Materials & Continua, Vol.17, No.2, pp. 103-126, 2010, DOI:10.3970/cmc.2010.017.103

Abstract This paper presents a novel mathematical framework for building a comprehensive materials knowledge system (MKS) to extract, store and recall hierarchical structure-property-processing linkages for a broad range of material systems. This new framework relies heavily on the use of computationally efficient FFT (Fast Fourier Transforms)-based algorithms for data-mining local structure-response-structure evolution linkages from large numerical datasets produced by established modelling strategies for microscale phenomena. Another salient feature of this new framework is that it facilitates flow of high fidelity information in both directions between the constituent length scales, and thereby offers a new strategy for concurrent multi-scale modelling of materials… More >

O. U. Ojeda¹ and T. Çagınˇ ¹

CMC-Computers, Materials & Continua, Vol.16, No.2, pp. 127-174, 2010, DOI:10.3970/cmc.2010.016.127

Abstract The large discrepancy in length and time scales at which characteristic processes of energetic materials are of relevance pose a major challenge for current simulation techniques. We present a systematic study of crystalline energetic materials of different sensitivity and analyze their properties at different theoretical levels. Information like equilibrium structures, vibrational frequencies, conformational rearrangement and mechanical properties like stiffness and elastic properties can be calculated within the density functional theory (DFT) using different levels of approximations. Dynamical properties are obtained by computations using molecular dynamics at finite temperatures through the use of classical force fields. Effect of defects on structure… More >

Hamad F. Al-Harbi¹, Marko Knezevic^1,2, Surya R. Kalidindi^1,3

CMC-Computers, Materials & Continua, Vol.15, No.2, pp. 153-172, 2010, DOI:10.3970/cmc.2010.015.153

Abstract In recent work, we have demonstrated the viability and computational advantages of DFT-based spectral databases for facilitating crystal plasticity solutions in face-centered cubic (fcc) metals subjected to arbitrary deformation paths. In this paper, we extend and validate the application of these novel ideas to body-centered cubic (bcc) metals that exhibit a much larger number of potential slip systems. It was observed that the databases for the bcc metals with a larger number of slip systems were more compact compared to those obtained previously for fcc metals with a smaller number of slip systems. Furthermore, we demonstrate in this paper that… More >

M.A.Arafin¹, J.A.Szpunar²

CMC-Computers, Materials & Continua, Vol.14, No.2, pp. 125-140, 2009, DOI:10.3970/cmc.2009.014.125

Abstract A novel microstructure, texture and grain boundary character based model has been proposed to simulate the intergranular crack propagation behavior in textured polycrystalline materials. The model utilizes the Voronoi algorithm and Monte Carlo simulations to construct the microstructure with desired grain shape factor, takes the texture description of the materials to assign the orientations of the grains, evaluates the grain boundary character based on the misorientation angle - axis calculated from the orientations of the neighboring grains, and takes into account the inclination of grain boundaries with respect to the external stress direction. Markov Chain theory has been applied to… More >

Edward Van Keuren¹, MakiNishida¹

CMC-Computers, Materials & Continua, Vol.14, No.1, pp. 61-78, 2009, DOI:10.3970/cmc.2009.014.061

Abstract Room temperature solution-based synthetic methods are an important option for the production of a wide range of nanomaterials. These methods often rely on self-assembly or self-organization of molecular precursors, with specific control of their nucleation and growth properties. We are developing strategies for the creation of multifunctional composite nanoparticles as well as models for predicting the bulk properties from the individual components and parameters of the processing conditions. One method of synthesis is a reprecipitation technique in which nanoparticle nucleation and growth is induced by the rapid injection of a molecular solution into a miscible non-solvent. Here we demonstrate that… More >

Chyanbin Hwu¹, T.L. Kuo, Y.C. Chen

CMC-Computers, Materials & Continua, Vol.11, No.3, pp. 165-184, 2009, DOI:10.3970/cmc.2009.011.165

Abstract In this paper the near tip solutions for interface corners written in terms of the stress intensity factors are presented in a unified expression. This single expression is applicable for any kinds of interface corners including corners and cracks in homogeneous materials as well as interface corners and interface cracks lying between two dissimilar materials, in which the materials can be any kinds of linear elastic anisotropic materials or piezoelectric materials. Through this unified expression of near tip solutions, the singular orders of stresses and their associated stress/electric intensity factors for different kinds of interface problems can be determined through… More >

G. Haasemann¹, M. Kästner¹ and V. Ulbricht¹

CMC-Computers, Materials & Continua, Vol.3, No.3, pp. 131-146, 2006, DOI:10.3970/cmc.2006.003.131

Abstract Novel textile reinforced composites provide an extremely high adaptability and allow for the development of materials whose features can be adjusted precisely to certain applications. A successful structural and material design process requires an integrated simulation of the material behavior, the estimation of the effective properties which need to be assigned to the macroscopic model and the resulting features of the component. In this context two efficient modelling strategies - the Binary Model (Carter, Cox, and Fleck (1994)) and the Extended Finite Element Method (X-FEM) (Moës, Cloirec, Cartraud, and Remacle (2003)) - are used to model materials which exhibit a… More >

X.G. Yuan¹, R.J. Zhang²

CMC-Computers, Materials & Continua, Vol.3, No.3, pp. 119-130, 2006, DOI:10.3970/cmc.2006.003.119

Abstract In this paper, the problem of cavity formation and motion in an incompressible transversely isotropic nonlinearly elastic solid sphere, which is subjected to a uniform radial tensile dead load on its surface, is examined in the context of nonlinear elastodynamics. The strain energy density associated with the nonlinearly elastic material may be viewed as the generalized forms of some known material models. It is proved that some determinate conditions must be imposed on the form of the strain energy density such that the surface tensile dead load has a finite critical value. Correspondingly, as the surface tensile dead load exceeds… More >

Lingfei Gao¹, Xiaoping Zheng^1,2, Zhenhan Yao¹

CMC-Computers, Materials & Continua, Vol.3, No.1, pp. 25-36, 2006, DOI:10.3970/cmc.2007.003.025

Abstract A general numerical approach is developed to model the elastic behaviours and failure processes of heterogeneous materials. The heterogeneous material body is assumed composed of a large number of convex polygon lattices with different phases. These phases are locally isotropic and elastic-brittle with the different lattices displaying variable material parameters and a Weibull-type statistical distribution. When the effective strain exceeds a local fracture criterion, the full lattice exhibits failure uniformly, and this is modelled by assuming a very small Young modulus value. An auto-select loading method is employed to model the failure process. The proposed hybrid approach is applied to… More >