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 Crankcase Aluminium Metal Alloy.
| Identifier | ExFiles\Box 76\3\ scan0050 | |
| Date | 26th April 1917 | |
| R.R. 235a (500 T) (S.D. 408. 26-4-17.) Bm. 2/156/13. ROLLS-ROYCE SPECIFICATION FOR CRANKCASE ALUMINIUM METAL ALLOY CHEMICAL COMPOSITION Copper 1.5 to 2.5 Zinc 9.0 to 12.0 Tin-Maximum 0.5 Silicon " 0.5 Iron " 0.8 Manganese " 0.25 Magnesium " 0.25 The composition should be such that Copper% + 3(Iron % + Manganese % + Magnesium %) should not exceed the value 5.5 Other impurities etc. only traces. 1" Test Bar (round) As sand cast should give a Brinell hardness figure of 55 to 80 (after 1/8" depth of surface having been removed before testing. 1" round Test Bar chill cast in mould at about 350° should give under the same conditions a Brinell figure of 70 to 97 and a tensile test result- M.S. Y.P. Elong^n R.A. 11.0 7.5 3.2 3.5 Stanton (drop of .312") stand 2000 blows. [Handwritten text] Three analyses per week (more if necessary) JCTD Periodic tensile Stanton besides crankcase T.P. Outside firms alloys - | ||