Preface to Special Issue on Hydrogen Embrittlement of Steel Materials and Its Evaluation by Electrochemical Hydrogen Permeation Monitoring

摘要

The improved quality of life in postwar Japan was made possible by new buildings, bridges, and other social infrastructures constructed from steel. The steel structural components of these infrastructures are now reaching the end of their service life. In view of long-term global energy and environmental concerns, they need to be replaced by ultra-high-strength steel components. In response to this social need, efforts are being made to develop ultra-high-strength steel species. Since high-strength steel materials are prone to hydrogen-induced embrittlement (HE), evaluation for HE is a major research concern in the development of ultra-high-strength steels.There are only a very limited number of techniques available for detecting hydrogen in steel and other metallic materials. The late Prof. Koji Yamakawa of Osaka Prefecture University and his collaborators made a significant contribution in this area. Concentrating their research efforts on electrochemical hydrogen permeation, they found that this monitoring method facilitated quantitative evaluations of the hydrogen diffusion coefficient and hydrogen concentration of the material. Using electrochemical hydrogen permeation monitoring, they described several significant aspects of the HE behavior of steel materials.