DETERMINATION OF PHOSPHORUS IN CAST-IRON AND STEELS

Application of the methods of spectrophotometry and field-emission spe ctrometry with induction-bonded plasma for determination of phosphorus in cast iron and steels is investigated. An efficient version of the ratio of various acids in their mixture (2 ml of concentrated HCI, 4 m l of concentrated HNO3, 3 ml of concentrated HF, and 3 ml of 6-M H2SO4 ) for complete quick stripping of specimens and their transfer into th e solution is found. Fifty specimens of alloys of different compositio ns Fe-Mn-P (70% Mn, 0.5% P) and Fe-Mn-Si-P (70% Mn, 20% Si, and 0.1% P ) are analyzed by the spectrophotometric method in the form of reduced heteropolyacids with extraction ending. Proper conditions for prepara tion of specimens are found, which make it possible to decompose them completely and quickly (in 30 min).