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When cracks form, microbeads embedded in the material break open and cause a chemical reaction that highlights the damaged area. Credit: Image courtesy Nancy Sottos

Damage developing in a material can be difficult to see until something breaks or fails. A new polymer damage indication system automatically highlights areas that are cracked, scratched or stressed, allowing engineers to address problem areas before they become more problematic. The early warning system would be particularly useful in applications like petroleum pipelines, air and space transport, and automobiles – applications where one part’s failure could have costly ramifications that are difficult to repair.

“Polymers are susceptible to damage in the form of small cracks that are often difficult to detect...