Characterization and modelling of helium bubbles in self-irradiated plutonium alloys

Abstract

The self-irradiation damage generated by alpha decay of Pu results in the formation of lattice defects and helium and uranium atoms. Over time, microstructural evolution as a result of the self-irradiation may influence the physical and mechanical properties of the material. Transmission electron microscopy investigations of Pu–Ga alloys ranging in age up to 42 years old, reveal the presence of nanometre-sized helium bubbles. The number density of bubbles and the average size have been determined for eight different age materials. The nucleation and growth of these bubbles have been modelled with rate equations.

Acknowledgements

The authors wish to thank Dennis Fleming, Rick Gross, Joe Magana, Bob McGee, and Larry Walkley of LLNL for their technical support. This work was performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48.

Disclaimer

This document was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor the University of California nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or the University of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or the University of California, and shall not be used for advertising or product endorsement purposes.