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).
Specifications, mixing instructions, and hardness details for an alloy.
| Identifier | ExFiles\Box 115\5\ scan0191 | |
| Date | 1st November 1938 | |
| -3- hm{Capt. W. Hallam - Head Repairs}/CTW.3/JH..1.11.38. The following are our answers to these questions - 1. Specification. Tin 5.5 - 7. Cu .6 - .9 Ni 1.4 - 1.7 Ti 0.25 - 0.4 Mg. 0.7 - 1.0 Iron. Max. 0.3 Sn.{Mr Sanderson} Max. 0.10 Mixing for 100 lbs. Tin 6 1/2 lbs. Cu. Alum. 50/50 1 1/2 " Ni. Alum 6 " Mg. 1 " Pure Alum 85 " --- 99 1/2 " First melt 65 lbs. of pure Alum at about 720°C then add Ni. Alum, and then balance of Pure Alum. 13 lbs. Add Cu. Alum and then the Mg. and Tin in quick succession. 2. The essence of this question is answered in the details of the standardisation process. See memo. attached. 3. Mg. is added if the material is molten for more than two hours, and is added at the rate of 1/2 oz. per 100 lbs. per hour. The same amount is used when remelting cast material. 4. Hardness of production bearings - 60 - 64 Brinell. Every bearing is tested on its outside dia. prior to machining. ***** | ||