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).
Failures and further testing related to cadmium plating on small screwed parts.
| Identifier | ExFiles\Box 30\6\ Scan068 | |
| Date | 17th December 1928 | |
| X1360 -BY.{R.W. Bailey - Chief Engineer} H14/EA171228. M632. Laboratory. c to Hs.{Lord Ernest Hives - Chair} Re Cadmium Plating on Small Screwed Parts. Your Ref. By2/G.14.12.28. We note that you are satisfied that the failures complained of definitely were not due to tightness of the thread after cadmium plating. We agree that, under the circumstances, the heat-treatment at 150°C is advisable as a precautionary measure, but, unless resistance to corrosion is a secondary consideration in connection with small screwed parts, it is necessary to add the proviso that further corrosion tests of the plated and heat-treated parts should be carried out. You may recollect that we drew your attention to some tests we made in this connection, which appeared to show that there is a lessening of the resistance to corrosion after the special heat-treatment. (See our memo. H13/EA20.9.28.). If, as suggested, there is some peculiar condition of the mild steel in which it is liable to made brittle by the plating operations, then it is evident that the material we have used was not in this condition, as our numerous tests failed to indicate any brittleness. If you have any of the original failed parts available, we should be interested to test these with a view to discovering any abnormality. We can also carry out a further series of tests on the Upton-Lewis machine, using similar screwed test pieces, if you consider that such tests would more closely approximate the conditions under which the original failures occurred. Hl. He | ||