A cracked metal disk from an airline engine. (NTSB)

Researcher developed a new method for testing metals at a microscopic scale that allows them to rapidly inflict repetitive loads on materials while recording how ensuing damage evolves into cracks.

The process has proven a connection between early, micron-scale damage to the eventual location of the fracture. The new method begins when metals are first exposed to loads that lead to localized damage that could become cracks.

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