Study of the distribution of chrome in 17Cr stainless steel by autoradiography using 51Cr

The segregation of alloying elements in steels even as small as undetectable in X-ray microanalysers seems to affect physical properties for instance, the ridging phenomenon in a 17Cr stainless steel sheet due to fine winkles of the surface by drawing, the mechanism of which is not yet clear. Study was made of a method for detecting small segregations by autoradiography using 51Cr for the 17Cr stainless steel. In results, (1) in the steel containing a 0.025% carbon or no carbon content, a small variation in photographic density relating to the concentration of chromium was found. (2) In the case of the steel with a 0.05% carbon content, similar one to commercial steel, a clear photographic density variation was observed which was considered to be a cause of the ridging. (3) The autoradiography is suitable to investigation of the small segregation undetected by an X-ray microanalyser. (author)