Review of the American Standard Specifications, Test Pieces, and Methods of Testing Iron and Steel, Adopted by Committee No. 1 of American Section of the International Association for Testing Materials; With a Discussion of the Commercial Methods for the (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1900 Excerpt: ...tions iQ detail, are the ones most generally used in of Phosphorus. American steel works laboratories, for the determination of phosphorus in steel. (a). The Drown-Emmerton method. Time, thirty minutes. Accuracy, 0.002%. ( ). The Handy-Manby method. Time, ten minutes. Accuracy, 0.003%. (a). The Drown-Emmerton Method.--This method depends on the conversion of all the phosphorus, in a nitric acid solution of the steel, into orthophosphoric acid by means of potassium permanganate; the reduction of the manganese dioxide formed, by a small amount of sugar; and the precipitation of the phosphorus by ammonium molybdate. The yellow precipitate may be weighed as such; or preferably dissolved in ammonium hydroxide, the solution acidulated with sulphuric acid, and the molybdic oxide, forming a known proportion of the phosphomolybdate precipitate, reduced to molybdous oxide by passing the solution through a column of amalgamated zinc, and then oxidizing by a standard solution of potassium permanganate. Attention has frequently been called to the many little details of the process which long experience has shown to be necessary, to insure accuracy. It is notably a method in which success is only attained by experience. The solution of the steel, and precipitation of the phosphorus, may be conveniently effected in an Erlenmeyer flask. The phosphorus is completely precipitated by agitation for five minutes. Suction is used in filtration; special forms of reductors and permanganate burettes have been devised which contribute materially to the rapidity of the process, and its adaptability to the determination of phosphorus in ten or twenty steels at a time. The method is accurate to within 0.002 % insteelsof o. 10% phosphorus or below. A single determination may be rea...