| 摘要 |
An aqueous solution containing 0.00005 to 0.2 mol/l of copper ion and 0.0001 to 1.0 mol/l of nitrate ion is effective to detect phosphorus segregates in a metallic material, particularly cast steel. Segregated phosphorus can be detected by etching a surface of steel to be tested, attaching test paper onto the steel surface, applying the aqueous solution to the paper, maintaining the paper in contact with the steel surface until stains appear, and removing the paper from the steel surface. A red print is obtained when the solution is pH 6 or higher. A blue print is obtained by following the above steps, and further treating the paper with a color reagent containing molybdate ion, and then with a reducing agent. |
