Laser surface melting of stainless steel anodes for reduced hydrogen outgassing

Anodes of 304 stainless steel have been processed by a continuous wave Yb fiber laser with a wavelength of 1.064 μm and subjected to 50 keV electron bombardment in order to determine the extent to which hydrogen outgassing is reduced by the laser surface melting treatment. The results show a reduction in outgassing, by approximately a factor of four compared to that from untreated stainless steel. This is attributed to a reduction in the number of grain boundaries which serve as trapping sites for hydrogen in stainless steel. Such laser treated anodes do not require post-processing to preserve the benefits of the treatment and are excellent candidates for use in high power source devices.