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).
Comparing the analytical results, properties, and costs of different valve steels.
| Identifier | ExFiles\Box 154a\1\ scan0076 | |
| Date | 9th June 1928 | |
| R. {Sir Henry Royce} BV. Hs. {Lord Ernest Hives - Chair} BK. {A. Birkett - Commercial Manager} X147 H113/EA9.6.28. Laboratory. Re Testing Valve Material. By9/G.8.6.28. The analytical results given in the above note were similar to those given in our memo. H11/EA8.6.28. It is suggested that the difference in relative stretch between the Firth's Crown steel and the K.E.Austenitic is mainly due to the difference in Silicon content, our figures being 0.52% for Firth's steel as compared with 1.48% for the K.E. The difference between the two steels is confirmed by the figures given in your note, for instance, maximum tensile of the H.R.Crown is given as 6 tons compared with 15 tons on the K.E. As noted in our memo. H11/EA4.6.28. we are doing further hot creep tests on actual test bars. We hope to report these next week. With respect to the relative difficulty in manufacture. It is thought that S.L.V./steel of about 3.25% silicon would be more easily dealt with from the steel makers' point of view and more easily forged and machined than the Austenitic Steels. There are indications that a slight increase in the chromium and reduction in the carbon content of the S.L.V. would tend to improve the steel from the mechanical standpoint. The relative cost is very much in favour of S.L.V. H1. HE | ||