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).
The heat-treatment and hardness testing procedures for castings.
| Identifier | ExFiles\Box 115\5\ scan0171 | |
| Date | 15th November 1938 | |
| Rm{William Robotham - Chief Engineer}/CTS.{C. Trot Salt - Carburation} H1.1/SK.15.11.38. Research Laboratory. 1020a. Re : Rm{William Robotham - Chief Engineer}/CTS.{C. Trot Salt - Carburation}2/MH.{M. Huckerby}12.11.38. ------------------------ 7. Heat-treatment should be done in the rough. (so that Brinell hardness tests can be obtained with a load of 500 Kilos. with 10 mm. ball.) 12 hrs. at 180°C. should be sufficient to get a hardness figure of 55 to 75. A second heat-treatment i.e. of 12 hrs. at 180°C. is permitted if bearings are slightly below 55 on first heat-treatment since longer ageing is no disadvantage in that case. The furnace or oven used should be of the air circulation type - similar to the "Birlec" seen during your visit. 5. Yes, with AC.9. the amount is important. Many castings have been examined with favourable report. It was suggested that the first and last ingot cast from each melt by H.D.A. should be heat-treated by them to confirm satisfactory response. (Continued) Hl. HC | ||