EXPLORATION OF ADDITIVELY MANUFACTURED METAMATERIALS FOR AEROSPACE APPLICATIONS

Abstract

This project aimed to investigate the energy absorption capabilities of symmetrical and asymmetrical mechanical metamaterial structures fabricated from Al7075 using Selective Laser Melting (SLM) on an AM400 printer. A critical initial step involved optimizing the SLM printing parameters for Al7075, a high-strength aluminum alloy challenging to process due to its susceptibility to cracking. Parameter optimization was conducted by systematically adjusting laser power and exposure time in batches, starting from an AlSi10Mg baseline, and evaluating the resulting mechanical properties, including compressive strength, hardness, and tensile strength. The optimization process successfully improved the compressive strength of the Al7075 material. Following parameter optimization, symmetrical and asymmetrical SSR honeycomb structures were printed and subjected to compression testing to assess their energy absorption performance. The asymmetrical 30∘ SSR design demonstrated an improved energy absorption capacity compared to the symmetrical structure, although both exhibited brittle fracture behavior under compression. This study highlights the potential of structural asymmetry in enhancing energy absorption in additively manufactured Al7075 metamaterials, while also underscoring the importance of robust parameter optimization and addressing material brittleness and testing methodology limitations for high-performance applications like aircraft wing leading edges.