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).
Letter from Specialloid Limited detailing the mechanical properties, manufacturing process, and performance of their Y alloy for piston purposes.
| Identifier | ExFiles\Box 148\4\ scan0289 | |
| Date | 22th September 1934 | |
| Specialloid LIMITED Friern Park North Finchley. N.12. -4- Messrs. Rolls Royce, Ltd., 22nd September, 1934. includes two large electrically heated air circulating furnaces with Automatic Graph and time control, all supplied by Messrs. Wild-Barfield & Co., with two spacious containers for the subsequent boiling water hardening treatment. The mechanical properties of the alloy, after complete heat-treatment, are:- Maximum stress..............17-20 tons per sq. in. Brinell...................100 - 110. Elongation..................3 - 5%. Impact......................3 - 5%. A characteristic feature of Specialloid Y alloy is the relative high impact value compared with the maximum strength and hardness which makes the material most suitable for Piston purposes. 6) MANUFACTURE: The maximum care is taken in the manufacture of the specialloid Piston but we shall not, at this stage, enter into minute details. Supervision of manufacture commences from the start for every alloy mix is checked by our own Metallurgical Laboratory, while following casting, heat-treatment and each machining operation - from spigot boring to the finish-turning - a detailed examination is made in addition to the final inspection. As Piston specialists we have studied machining requirements and have introduced many modifications to standard machines which have made it possible for us to produce Pistons within the fine limits for which we are noted. 7) PERFORMANCE: Until the last two years our activities have been confined to the commercial field and therefore the major part of our experience is with the commercial engine manufacturers. We have, however, successfully completed bench and road tests with:- Messrs. Aston Martin, Limited, " Frazer Nash Cars, Limited, " Lagondas, Limited, | ||