Abstract
In order to determine the underlying mechanism of hydrogen embrittlement, the secondary ion mass spectrometry (SIMS) is beneficial. However there has been no report on the use of SIMS to analyze hydrogen diffusion in carbon steels, because hydrogen diffuses in the steels at room temperature owing to their large diffusion coefficients. In this study, in order to introduce a large amount of hydrogen and a large number of trap sites in the test specimens, the specimens were subjected to a prestrain and hydrogen charging. In addition, SIMS used in this study had a stage with cooling system which limited the diffusion of hydrogen. The Hydrogen-charged specimen and uncharged specimen contained 0.14 ppm and 0.01 ppm hydrogen, respectively. SIMS-based analyses were performed using a raster area of fixed size and could detect hydrogen in a concentration of 0.14 ppm. The analyses were performed while changing the size of raster area and could detect hydrogen of the H-charged specimen in a concentration of 0.14 ppm and the uncharged specimen in a concentration of 0.01 ppm.
