| 摘要 |
PURPOSE:To enable quick detection of slaggy and powdery inclusions without using a darkroom or any special device by a method wherein detection paper impregnated with a color-forming mixed solution containing a derivative of a chromotropic acid is pressed against the ground surface of a steel material and then peeled off, and that part of the detection paper which has undergone discoloration is observed. CONSTITUTION:A color-forming mixed solution (containing 5-15% tartaric acid of 0.5-2% hydroxylamine hydrochloride) containing 0.005-0.02% derivative of a chromotropic acid (e.g. chlorophosphonazo III) is infiltrated, for instance, in photographic desilverized printing paper. After part of the solution is removed, the paper is against on the ground surface of a steel material for one minute and then peeled off. When slaggy and powdery inclusions are contained in the steel material, the color of that part of the surface of the peeled detection paper where these inclusions exist is changed into green 1 when chlorophosphonazo III is used, while the color of the other part is blue-violet 2. Thus, the inclusions can be detected quickly and simply. |
