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Why do gold nanowires have such high yield strength upon decreasing their size?

Why do gold nanowires have such high yield strength upon decreasing their size? Correct Answer Lack of dislocations

Gold nanowires are known to have ultra-high strength owing to the extreme increase in the yield strength approaching the theoretical value of E/10. This occurs due to the lack of dislocation in solid. Without dislocation motion, a ‘dislocation starvation’ mechanism is in operation. This leads to huge material stresses accordingly before dislocation motion and then material begins to strain-harden.

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