Density-Based Topology-Optimized 3D-Printed Fixtures for Cyclic Mechanical Testing of Lattice Structures

Area of Science:

• Materials Science
• Mechanical Engineering
• Additive Manufacturing

Background:

• Accurate experimental characterization of architected lattice materials under cyclic loading is crucial.
• Existing fixture systems often introduce parasitic effects, compromising load transfer reliability.
• There is a need for improved testing fixtures for lattice structures.

Purpose of the Study:

• To design and validate novel testing fixtures for cyclic load tests on lattice structures.
• To optimize fixture design using density-based topological optimization.
• To evaluate the performance of 3D-printed fixtures made from PLA filaments.

Main Methods:

• Density-based topological optimization was employed to design the testing fixtures.
• Finite element simulation was used to evaluate the optimized designs.
• Experimental testing was conducted to validate the performance of the PLA fixtures.
• Comparison with traditional machine clamps and metal test systems.

Main Results:

• The optimized PLA fixtures achieved a safety factor of 4.25, a significant improvement from the initial 2.08.
• Deformations were reduced by approximately 80% compared to standard machine clamps.
• Optimized PLA supports exhibited minimal displacement (around 0.73 mm) under load.
• Demonstrated rigid and reliable stress transfer to the lattice structure.

Conclusions:

• 3D-printed PLA fixtures are viable alternatives to conventional metal devices for mechanical testing of lattice materials.
• Optimized fixtures ensure accurate load transfer and minimize parasitic effects in cyclic testing.
• The study confirms the potential of additive manufacturing for creating specialized testing equipment.