Abstract
The recent progress of use of ultra-bright synchrotron radiation (SR) for environmental degradation studies of structural materials was reviewed. Refraction contrast X-ray imaging experiments were conducted in BL24XU of SPring-8 to aluminum alloys, mild steel, forged steel, etc. with cracks and voids. As a result, much more distinct images of cracks and voids in these materials were successfully observed by this new method, as compared with conventional X-ray absorption method. In-situ observations of crack initiation and propagation were also successfully done. SR-XAFS measurements were also conducted in SPring-8 to investigate the influence of hydrogen on the structure and electron state of titanium, and the influence of alloying elements on the formation and structure of iron rust to elucidate the corrosion mechanism of steel. In-situ XRD experiments were also performed in Spring-8 towards pure iron under wet and dry corrosion cycle so as to make sure so-called Evans model.
