Partition of plastic work into heat and stored energy in metals

This study investigates heat generation in metals during plastic deformation. Experiments were designed to measure the partition of plastic work into heat and stored energy during dynamic deformations under adiabatic conditions. A servohydraulic load frame was used to measure mechanical properties at lower strain rates, 10−3 s−1 to 1 s−1. A Kolsky pressure bar was used to determine mechanical properties at strain rates between 103 s−1 and 104 s−1. For dynamic loading, in situ temperature changes were measured using a high-speed HgCdTe photoconductive detector. An aluminum 2024-T3 alloy and α-titanium were used to determine the dependence of the fraction of plastic work converted to heat on strain and strain rate. The flow stress and β for 2024-T3 aluminum alloy were found to be a function of strain but not strain rate, whereas they were found to be strongly dependent on strain rate for α-titanium.

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