Hu Jianying, Zhou Yu, Liu Zishun, Ng Teng Yong
International Center for Applied Mechanics, State Key Laboratory for Strength and Vibration of Mechanical Structure, Shaanxi Engineering Research Center of Nondestructive Testing and Structural Integrity Evaluation, Xi'an Jiaotong University, Xi'an 710049, China.
School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore.
Polymers (Basel). 2017 Jun 16;9(6):229. doi: 10.3390/polym9060229.
It is well known that elastic instabilities induce pattern transformations when a soft cellular structure is compressed beyond critical limits. The nonlinear phenomena of pattern transformations make them a prime candidate for controlling macroscopic or microscopic deformation and auxetic properties of the material. In this present work, the novel mechanical properties of soft cellular structures and related hydrogel⁻elastomer composites are examined through experimental investigation and numerical simulations. We provide two reliable approaches for fabricating hydrogel⁻elastomer composites with rationally designed properties and transformed patterns, and demonstrate that different geometries of the repeat unit voids of the periodic pattern can be used to influence the global characteristics of the soft composite material. The experimental and numerical results indicate that the transformation event is dependent on the boundary conditions and material properties of matrix material for soft cellular structures; meanwhile, the deformation-triggered pattern of matrix material affects the pattern switching and mechanical properties of the hydrogel⁻elastomer material, thus providing future perspectives for optimal design, or serving as a fabrication suggestion of the new hydrogel⁻elastomer composite material.
众所周知，当软质多孔结构被压缩超过临界极限时，弹性不稳定性会引发图案转变。图案转变的非线性现象使其成为控制材料宏观或微观变形及负泊松比特性的主要候选对象。在当前这项工作中，通过实验研究和数值模拟，对软质多孔结构及相关水凝胶-弹性体复合材料的新型力学性能进行了研究。我们提供了两种可靠的方法来制备具有合理设计性能和转变图案的水凝胶-弹性体复合材料，并证明周期性图案重复单元空隙的不同几何形状可用于影响软质复合材料的整体特性。实验和数值结果表明，转变事件取决于软质多孔结构基体材料的边界条件和材料性能；同时，基体材料的变形触发图案会影响水凝胶-弹性体材料的图案切换和力学性能，从而为优化设计提供了未来展望，或作为新型水凝胶-弹性体复合材料的制备建议。
