Blisters and their surrounding crack-tip areas in AISI 304 stainless s
teel have been imaged by Scanning Photo-Electrochemical Microscopy (SP
EM), a technique providing photo-electrochemical images of hydrogen tr
apping and detrapping into blisters in real time, in situ and in conti
nuous under hydrogen charging. The increased hydrogen concentration ha
s also been imaged in the plastic enclave at the crack tip around a bl
ister during its growth. The images acquired in time sequence can be e
xamined as a single frame or assembled in a 2D or 3D movie, both in gr
ey scale or false colour. (C) 1997 Elsevier Science Ltd.