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).
Silicon Chrome Steel for valves, comparing a French study with an internal specification.
| Identifier | ExFiles\Box 54\3\ Scan208 | |
| Date | 25th August 1926 | |
| X.4634 Hs.{Lord Ernest Hives - Chair} H12/EA25.8.26. Laboratory. Re Silicon Chrome Steel for Valves. The results of the French experimental work reported in "Automotive Industries" of July 1st.1926 are quite reasonable. A higher Chromium than our specification,* if workable and machinable, should improve the steel in several respects. Our specification does not appear to have given trouble in graphite separation in spite of the fact that our Carbon and Silicon range is higher than recommended. We have had no opportunity of comparing the properties of this type of steel of varying composition, but it appears likely that the findings of the article in question are correct. Hl. He. *Specification 238A. Carbon -------- 0.40 to 0.50 % Silicon -------- 3.5 to 4.25 % Chromium ------- 7.5 to 8.5 % | ||