Continuum-Level Finite Element Modeling on Bi-Modulus Adaptive Metamaterial Designs

作者：Yunzheng Yang, Yaning Li · 年份：2025 · DOI：10.1115/imece2025-166249 · 研究领域：Cellular and Composite Structures、Nonlocal and gradient elasticity in micro/nano structures、Shape Memory Alloy Transformations

Abstract The concept of adaptive materials and adaptive mechanical metamaterials is fascinating, targeting dynamically altering properties (e.g., stiffness) in response to stimuli such as local stress or strain. However, it is challenging to computationally model this non-conventional constitutive behavior. This study presents a continuum finite element (FE) framework to simulate adaptive materials with on-demand bi-moduli using a user-defined material subroutine (UMAT) in ABAQUS. The UMAT updates element stiffness tensors in real time based on principal strain magnitudes: once it exceeds a critical threshold, stiffness tensor alters instantaneously, eliminating explicit microstructure modeling and therefore significantly reduce the computational cost. To validate the method, a 2D bi-modulus metamaterial design was proposed and analyzed under uniaxial compression and tension via both detailed microstructure FE models and UMAT-based continuum FE models. Results show strong agreement in stress-strain behavior from both models and a significant computational speedup with minimal accuracy loss. By the framework studied enables efficient design and evaluation of adaptive mechanical metamaterials without sacrificing mechanical fidelity. This approach bridges high-resolution modeling and computational efficiency, offering a tool for designing programmable materials for soft robotics, energy absorption, and adaptive systems and structures.