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Characterizing Dissipative Elastic Metamaterials Produced by Additive Manufacturing
Published on: June 28, 2024
Programming fracture resistance in metamaterials via elastic instabilities
Yujia Wang1,2, Yangchengyi Liu2, Kunlin Wu2
1Mechano-X Institute, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing, China.
Nature
|July 15, 2026
Summary
Researchers programmed fracture resistance in mechanical metamaterials by controlling elastic instabilities. This approach bridges failure modes, significantly increasing fracture energy and enabling tailored material design.
Area of Science:
- Materials Science
- Mechanical Engineering
- Physics
Background:
- Designing fracture-resistant materials is complex due to multi-scale toughening mechanisms.
- Mechanical metamaterials offer potential, but research often passively characterizes fracture in lattice structures.
- The link between elastic instabilities and fracture resistance in architected materials is unexplored.
Purpose of the Study:
- To demonstrate active programming of fracture behaviors in mechanical metamaterials using elastic instabilities.
- To bridge the traditionally disconnected failure modes of instability and fracture.
- To establish a new framework for designing metamaterials with tunable fracture resistance.
Main Methods:
- Combination of experimental investigations and computational simulations.
- Controlled manipulation of the inelastic zone size in pseudoplastic metamaterials.
- Exploitation of elastic instabilities to program fracture behaviors.
Main Results:
- Achieved active programming of fracture behaviors by exploiting elastic instabilities.
- Demonstrated a transition from intrinsic to extrinsic fracture behavior.
- Observed up to a one-order-of-magnitude increase in fracture energy.
Conclusions:
- Fracture mechanics can be actively controlled by programming elastic instabilities in metamaterials.
- This work shifts from passive observation to active control of fracture.
- Suggests a broadly applicable route for designing materials with tailored fracture resistance through instability design.
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