1965 Volume 51 Issue 7 Pages 1267-1274
For the research of fine minerals in rocks, a “polished thin section” began to beused as a new method. In this paper this technique was applied to metals containing non metallic inclusions. The metal sample was stuck to a slide glass, polished with emery paper to microns in thickness, and scratches on the surface of the inclusions were removed by polishing on cloth with alumina abrasive suspended in oil. Under a petrographic microscope the reflected and transmitted color, transparency, crystal shape, extinction and retardation of the non-metallic inclusions in the thin section were observed. From the optical properties the minerals in the inclusions were identified fairly well. Then, each of minerals was analysed with X-ray microanalyser. When the thin section was 7-8 microns in thickness, it was confirmed that the slide glass had no influence upon the X-ray microanalysis. By this method coarse non-metallic inclusions in the cold-rolled strips of rimmed steel made in openhearth furnace were examined. By considering both the optical properties and the result of X-ray microanalysis of the inclusions, the minerals in the inclusions were identified without difficulty and the state of coexistence of minerals was clarified in detail.