Numerical evaluation of hydrogen outgassing from copper electrodes with mitigation based on a tungsten capping layer
Abstract
Outgassing remains a pertinent issue for high power applications and is exacerbated by the high field driven, localized heating environments commonly encountered. Here, molecular dynamics simulations are performed for a simple model-based assessment of outgassing from electrodes. Our results of temperature dependent diffusion coefficients for hydrogen in copper agree well with experimental reports over a wide range spanning 300 K to 1330 K. Separate results are also obtained for transport of hydrogen to ascertain whether a grain-boundary would facilitate channeled transport or work to impede flow by clustering the gas atoms. Finally, the use of a tungsten overlayer on copper is evaluated as a material-based strategy for mitigating outgassing. It is demonstrated that a few monolayers of tungsten coating on the outer surface can be effective in significantly reducing outdiffusion at 700 K.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Sep 01, 2019
- Source ID
- 10.1063/1.5109682
Entities
People
- J. Acharjee
- R. P. Joshi
Organizations
- Air Force Office of Scientific Research
- Office of Naval Research
- Texas Tech University