Efficient 3D modeling of damage in composite materials

Abstract

Due to the complexity of composite material, numerical methods are generally utilized in their analysis and design. Commercial finite element (FE) codes, such as ANSYS and ABAQUS, allow the implementation of user subroutines in the program, which provides the advantage of using high meshing and solving technologies besides the improvement of materials and/or elements models. Nonlinearities arise for many engineering problems, for example, the progressive damage of a composite element that contains sources of stress concentration or damage localization such as holes, bolts, and/or flaws causes nonlinear material behavior. In order to simulate this nonlinear behavior, especially in 3D, an accurate material constitutive model is required. Therefore, the objective of this paper was to simulate the 3D progressive damage model of composite materials by using simple numerical models. In this paper, ANSYS user subroutine (USERMAT) was used to simulate the progressive damage behavior of a composite plate containing holes using simple models. Three different material models were used: ply discount model (PDM), simple progressive damage model (SPDM) by adding an empirical progressive damage criteria to the PDM, and continuum damage mechanics model (CDMM). Good agreements were observed between SPDM, CDMM, and published experimental results. Furthermore, CDMM showed the least dependence on mesh size. Three different damage evolution laws, linear, quadratic, and degradation laws, were adjusted and tested. It was found that there was no significant difference in the predicted failure load between these selected laws.

Investigation of interlayer hybridization effect on burst pressure performance of composite overwrapped pressure vessels with load-sharing metallic liner

“…48,49 The Hashin failure criterion has been commonly used for composite failure modeling as a first ply failure criterion, and it is also available as a built-in feature in ANSYS. 50–52 The failure modes and corresponding criteria were considered in the Hashin failure theory for 3D solid elements given in Table 3. Ff,t, Ff,c, Fm,t, and Fm,c indicate damage indices of failure modes of fiber tension, fiber compression, matrix tension, and matrix compression, respectively.…”

“…This model is similar to ply discount method except for the fact that the amount of degradation differs within a range between 0 and 1 for each failure mode. 50,52,54 It was assumed that a failure in the fiber dominated direction occurs due to failure of the fibers, and this results with catastrophic fracture or complete material degradation. Consequently, this causes a massive instant reduction in the mechanical properties along the fiber direction.…”

Progressive damage characteristics of screwed single-lap CFRPI-metal joint subjected to tensile loading at RT and 350°C

“…Ply discount model based on stiffness reduction seems simple but effective to define the progressive degradation in mechanical properties of damaged composite material, 26,27 here the reduction of stiffness is dependent on the individual failure mode. In other words, once element reaches failure, the stiffness matrix C of material is degraded according to ply discount model.…”

Static mechanical properties of hybrid RTM-made composite I- and Π-beams under three-point flexure

“…Thus it is argued that the progressive damage model presented in this paper has better precise than the ply discount model with a deviation of 26% in Literature. 31 Actually, based on the degradation rules of ply discount model, all elastic modulus in failure ply were completely degraded to be zero and the residual load-carrying capacity was entirely neglected. This resulted in a greater deviation of predicted results by the ply discount model from the experiments than that by using new progressive damage model presented in this paper.…”