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).
Specification document for Hykro Steel, detailing its chemical composition and mechanical properties.
| Identifier | ExFiles\Box 146\1\ scan0123 | |
| Date | 6th December 1937 guessed | |
| 1312 Volts SPECIFICATION FOR HYKRO STEEL. 1. Chemical Composition. - (a) The Chemical composition of the steel shall be :- Carbon .......... not less than 0.15 nor more than 0.35 per cent. Silicon .......... not more than 0.35 per cent. Manganese ........ not more than 0.65 per cent. Sulphur .......... not more than 0.05 per cent. Phosphorus ....... not more than 0.05 per cent. Nickel ........... not more than 0.30 per cent. Chromium ......... not less than 2.50 nor more than 3.50 per cent. Molybdenum ....... not less than 0.30 nor more than 0.70 per cent. The following elements may be present at the option of the Steelmaker Vanadium ......... not more than 0.25 per cent. Tungsten ......... not more than 1.00 per cent. (b) The complete analysis of every cast shall be supplied to the inspector. (2) Mechanical Tests (a) All tests shall be carried out to the satisfaction of the inspector. (b) The mechanical properties of the material shall be as follows - 0.1 per cent proof stress ..... (see footnote*). Maximum stress ............. not less than 60 nor more than 70 tons per square inch. Elongation ............... not less than 17 per cent. Izod ..................... not less than 35 ft. lb. Core test as specified in clauses not less than 25ft. lb. 16 (b) (iii) and 25 (A) (c) (iii) Brinnel hardness number ...... not less than 269 nor more than 321. Nicked fracture ............ see sub- para (f) below. * Note : When the purchaser requests that the 0.1 per cent proof stress shall be determined, the tests shall be made on the tensile test samples as specified in clauses 7 (a) 16, or 25, whichever is relevant and the value obtained must be not less than 45 tons. per sq.in. | ||