Abstract: 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.

Abstract: An aqueous electrolytic solution of a molybdate ion and an oxidizing agent is effective to detect phosphorus segregates in a metallic material, particularly cast steel through electrolysis. Segregated phosphorus can be detected by (a) applying a test sheet against a surface area of the metallic material to be examined for segregation, (b) introducing an aqueous electrolytic solution comprising 0.1 to 20% by weight of a molybdate ion and an oxidizing agent between the metallic material surface area and the sheet, (c) contacting a cathode plate with the sheet, (d) effecting electrolysis with the metallic material made anode, (e) removing the sheet from the metallic material surface, and (f) treating the sheet with a reducing agent.

Abstract: An aqueous solution of 0.1-80% silver nitrate is effective to detect phosphrous 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 an aqueous solution of 0.1 to 80% by weight of silver nitrate to the paper, maintaining the paper in contact with the steel surface for a sufficient time, removing the paper from the steel surface, and subjecting the paper to fixing treatment. The solution may further comprise an amount of lower alkyl alcohol that is compatible with the silver nitrate in solution.

Abstract: A sheet impregnated with an aqueous solution of silver nitrate 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 an aqueous solution of 0.1 to 80% by weight of silver nitrate to the test paper, maintaining the test paper in contact with the steel surface for a sufficient time, removing the test paper from the steel surface, and subjecting the test paper to fixing treatment.

Abstract: 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.

Abstract: Phosphorus segregates formed in cast steel upon solidifying are detected by a novel method comprising applying a metal etching reagent, for example, lithium chloride in ethanol, to a surface area of the steel to be examined, and attaching a sheet of test paper bearing an aqueous solution of silver nitrate to said surface, thereby detecting phosphorus segregates as stains on the sheet.

Abstract: An aqueous solution of silver nitrate 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 an aqueous solution of 0.1 to 80% by weight of silver nitrate to the paper, maintaining the paper in contact with the steel surface for a sufficient time, removing the paper from the steel surface, and subjecting the paper to fixing treatment.