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).
Experimental melt and casting properties of A.C.9 Bearing Material.
| Identifier | ExFiles\Box 116\2\ scan0110 | |
| Date | 1st November 1938 | |
| (COPY) RM{William Robotham - Chief Engineer}/CTS.{C. Trot Salt - Carburation}3/JH..1.11.38. A.C.9 Bearing Material - Time 11.00. An experimental melt of approximately 200 lbs. of this material was made in the Die Foundry on the 6th. The method of manufacture is detailed on attached sheet and was supervised by Mr. Hall. Various castings were then made to determine the casting properties of this material - (a) An ingot was cast in a cold mould at 710° to observe contraction and oxide formation - Liquid contraction - moderate. Solid contraction - high. Oxide formation on surface - very moderate. The oxide formation was considerably less than that which occurs with RR7. (b) Castings were then made from a ring die making RR.2610. These castings were made with the die in an horizontal position, at the following temperatures - 1 - Cast at 690° 2 - " 670° 3 - " 680° 4 ) 5 ) - " 680° 6 ) One was also cast at 680° and fractured, the fracture being quite clean. The material when molten is quite fluid and 680° is a feasible casting temperature. | ||