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 for a piston alloy, detailing its chemical composition and mechanical properties.
| Identifier | ExFiles\Box 76\3\ scan0048 | |
| Date | 26th April 1917 | |
| R.R. 255A (500 T) (S.D. 408. 26-4-17.) Bm. 2/156/13. ROLLS-ROYCE SPECIFICATION FOR PISTON ALLOY CHEMICAL COMPOSITION Copper 6.0 to 7.5% Zinc Max 0.5 Tin " 0.2 Iron " 0.8 Silicon Max 0.5 Manganese " .35 Magnesium .35 The composition should be such that Copper + 3 (Iron + Manganese + Magnesium) should not exceed the value 10.6 Only traces of other constituents and impurities. 1" round test bar cast in sand mould should give a Brinell hardness figure of 52 to 72 (1/8" below surface). 1" round bar cast in chill mould at about 350°C. should give Brinell figure of 65 to 90 and the mechanical results below Tensile M.S. Y.P. Elongation R.A. 10 8.0 2.5% 2.5% Stanton (3 1/2" d x 1/2") At least 250 blows JHCSn | ||