THE STRUCTURE and composition of the substrate metal is of extreme importance insofar as the corrosion mechanism is concerned. In order to understand better the corrosion mechanism it often is desirable to observe changes in the composition or structure of the alloy as the reaction is proceeding. The object of this report is to describe preliminary work in progress involving the use of an X-ray microscope to observe such changes in alloy structure.
The theory and operation of the X-ray microscope was described by Newberry1 and its potential applications to surface reactions were discussed in a recent report from this laboratory.2 In the present work a General Electric Type A5001 shadow X-ray microscope is used. The X-ray beam traverses a thickness of about 0.003 inch of the alloy under study. The details of the X-ray picture recorded on the photographic plate arise from the differences in the absorption...
