Biswakarma John J S, Cruz Dario A, Bain Erich D, Dennis Joseph M, Andzelm Jan W, Lustig Steven R
Department of Chemical Engineering, Northeastern University, 360 Huntington Avenue, Boston, MA 02115, USA.
Engineering Systems, Inc., 10338 Miller Rd., Dallas, TX 75238, USA.
Polymers (Basel). 2021 Oct 1;13(19):3387. doi: 10.3390/polym13193387.
Linear elastic fracture modeling coupled with empirical material tensile data result in good quantitative agreement with the experimental determination of mode I fracture for both brittle and toughened epoxy nanocomposites. The nanocomposites are comprised of diglycidyl ether of bisphenol A cured with Jeffamine D-230 and some were filled with core-shell rubber nanoparticles of varying concentrations. The quasi-static single-edge notched bending (SENB) test is modeled using both the surface-based cohesive zone (CZS) and extended finite element methods (XFEM) implemented in the Abaqus software. For each material considered, the critical load predicted by the simulated SENB test is used to calculate the mode I fracture toughness. Damage initiates in these models when nodes at the simulated crack tip attain the experimentally measured yield stress. Prediction of fracture processes using a generalized truncated linear traction-separation law (TSL) was significantly improved by considering the case of a linear softening function. There are no adjustable parameters in the XFEM model. The CZS model requires only optimization of the element displacement at the fracture parameter. Thus, these continuum methods describe these materials in mode I fracture with a minimum number of independent parameters.
线性弹性断裂建模与经验材料拉伸数据相结合，对于脆性和增韧环氧纳米复合材料的I型断裂实验测定，在定量上能取得良好的一致性。这些纳米复合材料由双酚A二缩水甘油醚与Jeffamine D - 230固化而成，部分填充了不同浓度的核壳橡胶纳米粒子。准静态单边切口弯曲（SENB）试验采用Abaqus软件中实现的基于表面的内聚区（CZS）和扩展有限元方法（XFEM）进行建模。对于每种考虑的材料，通过模拟SENB试验预测的临界载荷用于计算I型断裂韧性。当模拟裂纹尖端的节点达到实验测量的屈服应力时，这些模型中开始出现损伤。通过考虑线性软化函数的情况，使用广义截断线性牵引 - 分离定律（TSL）对断裂过程的预测有了显著改进。XFEM模型中没有可调整参数。CZS模型仅需要对断裂参数处的单元位移进行优化。因此，这些连续介质方法用最少数量的独立参数描述了这些材料的I型断裂。
