Evaluation of the relationship between hydrogen distribution by operando hydrogen microscope and crystal structures by EBSD

抄録

Hydrogen causes hydrogen embrittlement of metals, causing cracks and fractures. In order to clarify the hydrogen embrittlement of metals, it is necessary to visualize and analyze the crystal structures, crystallographic orientation, and hydrogen distribution. In this study, we aimed to obtain information related to the crystal structure and crystallographic orientation that is correlated with the distribution of hydrogen by image fusion [1] of the images obtained with scanning electron microscope (SEM), and electron backscattered diffraction (EBSD), and time-course hydrogen distributions in metals using an operando hydrogen microscope [2] based on electron stimulated desorption (ESD). The hydrogen gas was supplied to backside of a pure vanadium plate, penetrates the sample inside, and arrives at the surface. The hydrogen distribution at the vanadium surface was measured with the operando hydrogen microscope for 40 hrs. Hydrogen maps were measured every 150 s, a SEM image, and EBSD images including inverse pole figure (IPF) Kernel Average Misorientation (KAM), band contrast, and Euler angle maps were integrated using image registration (Matlab). The fused image data set was analyzed using multivariate analysis and the relationship between crystal structures and hydrogen permeation was indicated. References [1] T. Akiyama, N. Miyauchi, A.N. Itakura, T. Yamagishi, and S. Aoyagi, Journal of Vacuum Science & Technology B, 38, 034007 (2020) [2] N. Miyauchi, K. Hirata, Y. Murase, H.A. Sakaue, T. Yakabe, A.N. Itakura, T. Gotoh, S. Takagi, Scripta Materialia 144, 69 (2018).