Xu Rui, Bouby Céline, Zahrouni Hamid, Ben Zineb Tarak, Hu Heng, Potier-Ferry Michel
Laboratory of Excellence on Design of Alloy Metals for Low-Mass Structure (Labex-DAMAS), Université de Lorraine, 57070 Metz, France.
School of Civil Engineering, Wuhan University, 8 South Road of East Lake, Wuchang, 430072 Wuhan, China.
Materials (Basel). 2018 Sep 17;11(9):1746. doi: 10.3390/ma11091746.
In this paper, the superelasticity effects of architected shape memory alloys (SMAs) are focused on by using a multiscale approach. Firstly, a parametric analysis at the cellular level with a series of representative volume elements (RVEs) is carried out to predict the relations between the void fraction, the total stiffness, the hysteresis effect and the mass of the SMAs. The superelasticity effects of the architected SMAs are modeled by the thermomechanical constitutive model proposed by Chemisky et al. 2011. Secondly, the structural responses of the architected SMAs are studied by the multilevel finite element method (FE 2 ), which uses the effective constitutive behavior of the RVE to represent the behavior of the macroscopic structure. This approach can truly couple the responses of both the RVE level and structural level by the real-time information interactions between two levels. Through a three point bending test, it is observed that the structure inherits the strong nonlinear responses-both the hysteresis effect and the superelasticity-of the architected SMAs at the cellular level. Furthermore, the influence of the void fraction at the RVE level to the materials' structural responses can be more specifically and directly described, instead of using an RVE to predict at the microscopic level. Thus, this work could be referred to for optimizing the stiffness, the hysteresis effect and the mass of architected SMA structures and extended for possible advanced applications.
在本文中，通过采用多尺度方法来研究仿生形状记忆合金（SMA）的超弹性效应。首先，在细胞水平上对一系列代表性体积单元（RVE）进行参数分析，以预测孔隙率、总刚度、滞后效应与形状记忆合金质量之间的关系。仿生形状记忆合金的超弹性效应由Chemisky等人在2011年提出的热机械本构模型进行建模。其次，采用多级有限元方法（FE2）研究仿生形状记忆合金的结构响应，该方法利用代表性体积单元的有效本构行为来表征宏观结构的行为。这种方法能够通过两级之间的实时信息交互，真正地将代表性体积单元级和结构级的响应耦合起来。通过三点弯曲试验观察到，该结构在细胞水平上继承了仿生形状记忆合金强烈的非线性响应——滞后效应和超弹性。此外，能够更具体、直接地描述代表性体积单元级的孔隙率对材料结构响应的影响，而不是在微观层面使用代表性体积单元进行预测。因此，这项工作可为优化仿生形状记忆合金结构的刚度、滞后效应和质量提供参考，并可扩展到可能的先进应用中。
