Layered hybrid lattice architectures for broadband electromagnetic absorption and improved structural stiffness

Area of Science:

• Materials Science
• Electromagnetics
• Mechanical Engineering

Background:

• Electromagnetic interference (EMI) is a significant challenge in modern electronics.
• Metamaterial absorbers offer excellent electromagnetic wave attenuation but often lack mechanical stiffness.
• Existing solutions struggle to balance electromagnetic performance with structural integrity.

Purpose of the Study:

• To develop a new class of layered hybrid lattice absorbers with enhanced mechanical stiffness and broadband electromagnetic wave absorption.
• To investigate the relationship between lattice arrangement and combined electromagnetic and mechanical performance.
• To provide a framework for next-generation multifunctional absorbers.

Main Methods:

• Development of three-layer hybrid lattices combining simple cubic (SC), body-centered cubic (BC), and octet-truss (OT) architectures.
• Finite element simulations to evaluate electromagnetic responses and effective stiffness across the 4-18 GHz frequency range.
• Analysis of lattice arrangement effects on impedance matching, energy redistribution, and load-bearing capacity.

Main Results:

• The octet-truss (OT) lattice in the upper layer achieved >95% average EM absorption due to improved impedance matching.
• The SC lattice in the lower layer enhanced load-bearing capacity.
• The OT-SC-SC configuration demonstrated ~36% greater out-of-plane and ~118% greater in-plane stiffness compared to OT-OT-OT, while maintaining strong EM absorption.

Conclusions:

• Tailored spatial arrangement of lattice types enables simultaneous optimization of electromagnetic and mechanical functionalities.
• Positioning an OT lattice at the top and an SC lattice at the bottom is an effective strategy for multifunctional metamaterial absorbers.
• This approach provides a foundation for advanced EMI shielding and mechanically resilient applications.