Hydrogen embrittlement and strain rate sensitivity of electrodeposited copper: part II – hydrogen dynamics

In part I of this study, a previously unexplained form of hydrogen embrittlement and strain rate sensitivity was observed in electrodeposited copper. Here, the authors explored the dynamics of retained hydrogen in electrodeposited copper. Thermal desorption analyses were performed to characterize hydrogen trap energies of 0.39 ± 0.05, 0.63 ± 0.04, and 1.1 ± 0.04 eV. Annealing was conducted to evaluate the possibility of baking out hydrogen from electrodeposited copper and restoring ductility. A new electrodeposited material which is a candidate for coating used nuclear fuel containers was synthesized using tailored electrodeposition parameters, resulting in only 3.03 ± 0.58 ppm hydrogen, as compared to 26.4 ± 1.0 ppm. The mobility of hydrogen as it relates to embrittlement is discussed, and it is proposed that only hydrogen stored in low-energy trap sites contributes to embrittlement.