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).
Laboratory report on the nitriding of austenitic steel cylinder liners.
| Identifier | ExFiles\Box 154a\1\ scan0249 | |
| Date | 20th February 1932 | |
| Rg.{Mr Rowledge} Dv. (crossed out) Hs.{Lord Ernest Hives - Chair} RHC.{R. H. Coverley - Production Engineer} (crossed out) X4460 RECEIVED FEB 1932 20.2.32. Laboratory. Re: NITRIDING OF AUSTENITIC STEEL CYLINDER LINER. As stated in our previous communication we have further investigated this problem. Two test pieces were nitrided at 560°C as is works practice. This was carried out at a lower dissociation than is usual. It was found that the copper plated specimen did not nitride quite so well as the unplated specimen. A further test was run in which the temperature range was increased to 550 - 580°C. The dissociation was also increased in order to bring the test into line with works procedure. On this occasion it was found that the copper plate was a help to the reaction. It would appear therefore that the intended procedure of copper plating before nitriding will be a help. We wish to emphasise however that this copper plate must be as thin as possible. Also the dissociation must be kept to as low a figure as possible, and the cylinders must be arranged in the box so as to ensure as complete circulation of ammonia as possible. If this is not done the case will be altogether too brittle and weak, and will be thin. Even with a very low dissociation figure the line of demarcation between the case and core is very sharp, and the case itself is very brittle. To us it does not seem a practical proposition for regular use, with our present knowledge of nitrided austenitic steel, although success might be achieved with a greatly increased flow of ammonia and special arrangement of the liners and delivery of the gas. Hl. J.H.E. | ||