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).
Micro-examination report on a sample of bearing metal.
| Identifier | ExFiles\Box 115\1\ scan0038 | |
| Date | 25th June 1936 | |
| 41070 Micro-Examination Report. M.1156. To BY.{R.W. Bailey - Chief Engineer} c. Hs.{Lord Ernest Hives - Chair} c. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} HL6/AG.25.6.36. Laboratory. Re: Sample of Bearing Metal from D.{John DeLooze - Company Secretary} McIntyre, Sandgate House, Lichfield Rd. Four Oaks. The results of the tests we have made on the above up to the present are :- Micro-Examination : The structure indicated an alloy of about 10% copper, with the copper constituent evenly distributed and well broken up - see photomicrograph No. A1442. The lead content was small (estimated at less than 2%), consisting of small particles distributed irregularly as shown in A1443. The graphite was not detected microscopically. Analysis : This confirmed the microscope estimation with regard to copper and lead. Copper ... 10.8% Lead ... 1.5% Graphite ... Less than 0.1% Brinell Hardness : 89 Specific Gravity : 3.00 Fracture : The material was found to be rather brittle. We have tested an alloy of similar composition but without the graphite for friction properties and found that it was difficult to run in and inclined to pick up under heavy load when the temperature exceeded 120°C. This temperature is often exceeded in our engines. Hl. HE Two photomicrographs Nos. A1442/3 att. to BY.{R.W. Bailey - Chief Engineer} only. | ||