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).
Comparison of physical properties for material grades 'Z' and 'EG3417'.
| Identifier | ExFiles\Box 165\6\ img089 | |
| Date | 27th June 1927 | |
| E.{Mr Elliott - Chief Engineer} Fowler-Clark, Esq., Messrs. Rolls Royce Ltd. -2- 27th June, 1927. Grade "Z" Grade "EG3417" Specific Resistance (ohms per cu. inch) 0.0012 0.0006 Admissable load (amps. per sq. inch) 50 65 Contact drop in volts 1.80 2.5 Maximum speed (feet per min.) 4000 5000/6000 Friction co-efficient 0.22 0.23 R/EP.{G. Eric Platford - Chief Quality Engineer} OL.256. | ||