Permeation and Retention Behavior of Deuterium in Tungsten-Copper Composites

The permeation and retention of hydrogen isotopes in tungsten-copper composites were studied. The permeability, diffusion coefficient, solubility and activation energy of deuterium in tungsten and tungsten-copper composites were obtained by gas driven permeation and thermal desorption spectroscopy, and the permeation and retention properties of deuterium in tungsten-copper composites were also analyzed. The results show that the permeability of deuterium in tungsten-copper composite material is 2 similar to 3 orders of magnitude larger than that of pure tungsten, and the diffusion coefficient of deuterium in tungsten-copper composite material is 5 similar to 6 orders of magnitude larger than that of pure tungsten. With the increase of copper content in the composite, the permeability and diffusion coefficient of deuterium increase. The phase interface between tungsten-copper composites acts as a deuterium fast diffusion channel. The solubility of deuterium in tungsten-copper composites is much smaller than that of pure tungsten, and the dissolution activation energy is also larger, indicating that copper may have a weakened effect on the solid solution of deuterium in tungsten, which is consistent with the conclusion that deuterium diffuses rapidly in tungsten-copper composites. The apparent retention of deuterium in tungsten-copper composites is approximately 1 order of magnitude higher than that in pure tungsten because the deuterium trapped in the tungsten-copper composites cannot be released in time due to rapid cooling in the gas absorption experiment.