Mechanical Behavior of Topology-Optimized Lattice Structures Fabricated by Additive Manufacturing

Area of Science:

• Materials Science
• Mechanical Engineering
• Computational Mechanics

Background:

• Lattice-based metamaterials offer excellent mechanical properties but designing their complex topology is challenging.
• Achieving desired material properties like high stiffness and elastic isotropy requires advanced design methodologies.

Purpose of the Study:

• To design high-performance lattice structures with maximum bulk modulus and elastic isotropy.
• To investigate the mechanical behavior of topology-optimized lattices compared to traditional designs.

Main Methods:

• Utilized the bidirectional evolutionary structural optimization (BESO) method for topology optimization.
• Generated diverse lattice configurations by controlling filter radius during optimization.
• Fabricated optimized lattices using Stereo Lithography Appearance (SLA) printing technology.

Main Results:

• Topology-optimized lattices demonstrated superior modulus, yield strength, and specific energy absorption compared to octet-truss (OT) and body-centered cubic (BCC) lattices.
• Optimized structures showed reduced dependence on loading direction for yield stress and post-yield stress.
• Experimental and numerical simulations validated the enhanced mechanical performance.

Conclusions:

• The BESO method is effective for designing novel, high-performance lattice metamaterials.
• Topology optimization enables the creation of lattice structures with tailored mechanical properties and improved isotropy.
• This approach offers a pathway to advanced materials with enhanced stiffness and energy absorption capabilities.