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arXiv · 1508.02112

In situ monitoring of plastic deformation using ultrasound

Vicente Salinas·Fernando Lund·Nicolás Mujica·Rodrigo Espinoza-González
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Abstract

Ultrasound has long been used as a non-destructive tool to test for the brittle fracture of materials. Could it be used as a similar tool to test for ductile failure? This study reports results of local measurements of the speed of shear waves, $v_T$, in aluminum under standard testing conditions at two different locations on the same sample, as a function of stress. There is a clear change in $v_T$ at the Yield stress, consistent with a proliferation of dislocations. This measurement provides a quantitative, continuous relation between dislocation density and externally applied stress.

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Vicente Salinas, Fernando Lund, Nicolás Mujica, Rodrigo Espinoza-González. 2015-08-10. In situ monitoring of plastic deformation using ultrasound. https://arxiv.org/abs/1508.02112

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