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).
900°C heat treatment process to prevent staining on steel and cast iron parts by creating a magnetic oxide layer.
| Identifier | ExFiles\Box 66\2\ scan0186 | |
| Date | 16th April 1926 | |
| - 2 - treatment to approximately 900°C. I am inclined to think this is the process used by the people I am in touch with, who are responsible for the protection of huge quantities of mild steel parts which are used in processes where oxide of iron would be absolutely fatal if it were able to come adrift or cause a stain. Washing boilers for linen, and many other parts are produced by the process. The reason why staining etc. does not occur is, the magnetic oxide expands and contracts at the same rate as the steel upon which it is deposited, and further, the magnetic oxide itself is permanent and a final product, representing the final state to which all oxides of iron will, given time and the right conditions, arrive, but beyond which they never pass. This treatment is good for cast iron pieces as well as mild steel. I therefore propose to treat the cast iron exhaust pipe at the same time. BY. {R.W. Bailey - Chief Engineer} | ||