Metamaterials design with a desired thermal expansion using a multi-material BESO method

Author(s)

Anaya-Jaimes, L. M. ; Vicente, W. M. ; Pavanello, R.

• Document type: Journal article
• Source: STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION; v. 65, n. 12, p. 17-pg., 2022-12-01.

Abstract

The use of computational evolutionary strategies in the design of metamaterials with desired thermal expansion coefficients is uncommon due to the discrete nature of the design variables. This work presents a Bi-directional Evolutionary Structural Optimization (BESO) based methodology for designing orthotropic metamaterials with a specific thermal expansion coefficient using an objective function considering only the thermal expansion coefficients, with no constraints on geometry or stiffness. Topologies of the metamaterials, composed of two material phases and a void, are obtained using a material interpolation between neighboring material phases and three easy-to-implement numerical strategies to stabilize the evolutionary process. Two are on the sensitivity calculation and one is on the addition ratio's value. The strategies applied to the sensitivity numbers are proposed to avoid the positive and negative values of the elemental sensitivity numbers and the element change between no neighboring materials. Additionally, the addition ratio's value reduction strategy assures the convergence of the thermal expansion properties to the desired value. The homogenization method is used to obtain the equivalent thermal expansion properties of the designed materials. Some numerical examples are presented to show the potential and effectiveness of the proposed methodology. (AU)

• FAPESP's process: 13/08293-7 - CCES - Center for Computational Engineering and Sciences
• Grantee: Munir Salomao Skaf
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC