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).
Proposing a trial of the nitriding process on valves made from HR Crown steel for a skin hardening effect.
| Identifier | ExFiles\Box 154a\1\ scan0174 | |
| Date | 29th October 1929 | |
| HB.{C. E. Harcombe} c.Hs.{Lord Ernest Hives - Chair} e.Wor{Arthur Wormald - General Works Manager} X4469 BY/EM1/J.29.10.29. VALVES IN HR CROWN STEEL. We believe that it is possible to apply the nitriding process to the above material in order to obtain a very slight skin hardening effect. We should like to have this tried out as one of the main disadvantages of this or any other type of austenitic steel is the tendency to pick up and the difficulty to obtain really suitable material for valve guides. We believe the correct treatment to apply, is to heat the parts as for ordinary nitriding, but the temperature should be 600°C and the time 10 hours. We have some HR Crown material at present in store, and we should like you to try out some samples in order to test the possibility of treating valves in a similar manner. BY/EM. | ||