| 摘要 |
PURPOSE:To simply judge the deterioration degree of low alloyed steel with high sensitivity, by taking note of natural potential generated by contacting low alloyed steel with a specific acidic solution. CONSTITUTION:The deterioration degree of low alloyed steel due to heat history is judged by measuring natural potential generated by contacting low alloyed steel with an aqueous solution of an aromatic compound having at least one of a hydroxyl group or a carboxyl group and a nitro group in the molecule thereof. As the above-mentioned compound, 2,4,6-trinitrophenol, trinitroresorcine and 2,4-dinitrobenzoate are employed and four kinds of Cr-Mo-V steels different in a brittleness degree are immersed in each solution to measure natural potential. In the graph, the axis of abscissa is ductility brittleness transition temp. difference DELTAFATT being the parameter of the brittleness degree of steel and the axis of ordinate is natural potential measured on the basis of a saturated calomel electrode. In both cases, natural potential linearily changes corresponding to the brittleness degree. |
