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).
Material embrittlement during the cadmium plating process and the necessity of post-plating heat treatment.
| Identifier | ExFiles\Box 30\6\ Scan069 | |
| Date | 19th December 1928 | |
| Mr. c. Hs.{Lord Ernest Hives - Chair} X1360 BY5/G.19.12.28. re MATERIAL EMBRITTLED DURING THE PLATING OPERATION. -------------------------------------------------- I am afraid that it is difficult to hand on bars which we know will be embrittled during cadmium plating, but we are quite certain from our experience that it has happened in the past and will happen again in the future if the heat treatment after plating is omitted. I am sending you herewith two samples which I happen to have had left over which show the effect referred to. Both pieces were produced from the same bar, and in three samples of each which we bent, the unplated pieces were consistently good, the plated pieces were exactly similar to sample, i.e. the angle through which the steel could be bent was approximately halved. I am sending you the samples so that you can thoroughly check same to see whether any special peculiarity in the unplated steel can be located, which is likely to account for the embrittlement during plating. The fact that the Air Ministry have issued an A.I.D. regulation insisting on heat treatment after plating would certainly appear to confirm that they have had similar experience to myself. BY.{R.W. Bailey - Chief Engineer} Br | ||