From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Chemical analysis procedures for determining tin, manganese, silicon, and iron content.
| Identifier | ExFiles\Box 116\2\ scan0107 | |
| Date | 21th November 1938 | |
| -4- 5. Yes, with A.C.9 the amount is important. Many castings have been examined with favourable report. It was suggested that the first and last ingot cast from each melt by N.A.A. should be heat treated by them to confirm satisfactory response. Determination of tin. Dissolve 1 gm. of drillings in 100 cc. of 30% hydrochloric acid, in an atmosphere of carbon dioxide. Ensure that soln. of aluminium and tin is complete and then cool to below 20 °C. Titrate with N/20 iodine soln. When oxidation of the tin is complete, one drop of soln. in excess will give a yellow colour. Determination of Manganese. Dissolve 1 gm. of drillings in 25 cc. of 10% caustic soda. Acidify with dilute sulphuric acid and add 5 cc. of nitric acid. When soln. is complete add 10 cc. of 1% Silver Nitrate soln. make up to 100 cc. and bring to the boil. Add 1 gm. of ammonium persulphate and boil for 1 min. Cool and titrate with standard sodium arsenite. Determination of Silicon. Dissolve 2 gm. of the alloy in aqua regia evaporate to fuming with sulphuric acid, dilute with 10% hydrochloric acid and boil till all in soln. except silica. Filter and wash with 5% hydrochloric acid soln. ignite and weigh. Determination of Iron. Colorimetric with ammonium thiocyanate as for R.R. 50 using a corresponding blank. | ||