Yang Danhui, Yang Zhibo, Zhai Zhi, Chen Xuefeng
The State Key Laboratory for Manufacturing Systems Engineering, Xi'an 710054, China.
School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
Materials (Basel). 2019 Sep 19;12(18):3048. doi: 10.3390/ma12183048.
In this contribution, the ratcheting behavior and local field distribution of unidirectional metal matrix composites are investigated under cyclic loading. To that end, we extended the finite-volume direct averaging micromechanics (FVDAM) theory by incorporating the rule of nonlinear kinematic hardening. The proposed method enables efficient and accurate simulation of the ratcheting behavior of unidirectional composites. The local satisfaction of equilibrium equations of the FVDAM theory facilitates quick and rapid convergence during the plastic iterations. To verify the proposed theory, a finite-element (FE) based unit cell model is constructed with the same mesh discretization. The remarkable correlation of the transverse response and local field distribution generated by the FVDAM and FE techniques demonstrates the effectiveness and accuracy of the proposed models. The stress discontinuities along the fiber/matrix interface that are generic to the finite-element theory are absent in the FVDAM prediction. The effects of thermal residual stresses induced during the consolidation process, as well as fiber orientations, are revealed. The generated results indicate that the FVDAM is well suited for simulating the elastic-plastic ratcheting behavior of metal matrix composites, which will provide the conventional finite-element based technique with an attractive alternative.
在本论文中，研究了单向金属基复合材料在循环载荷作用下的棘轮行为和局部场分布。为此，通过纳入非线性运动硬化规则，扩展了有限体积直接平均微观力学（FVDAM）理论。所提出的方法能够高效、准确地模拟单向复合材料的棘轮行为。FVDAM理论平衡方程的局部满足性有助于在塑性迭代过程中快速收敛。为验证所提出的理论，构建了具有相同网格离散化的基于有限元（FE）的单胞模型。FVDAM和FE技术产生的横向响应与局部场分布的显著相关性证明了所提模型的有效性和准确性。FVDAM预测中不存在有限元理论中常见的沿纤维/基体界面的应力不连续性。揭示了固结过程中产生的热残余应力以及纤维取向的影响。所得结果表明，FVDAM非常适合模拟金属基复合材料的弹塑性棘轮行为，这将为传统的基于有限元的技术提供一个有吸引力的替代方案。
