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 piston alloy, detailing chemical composition and mechanical properties.
| Identifier | ExFiles\Box 76\3\ scan0051 | |
| Date | 26th April 1917 | |
| R.R. 235A (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 (1/2" 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. 10 Y.P. 8.0 Elongation 2.5% R.A. 2.5% Stanton (3 1/2" drop) At least 250 blows (Handwritten calculation on right) 7.3 1.71 8/75 10.63 (Handwritten note at bottom) Daily analysis, One stanton, one tensile p week. HCSL | ||