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).
The properties and hardening of steel for magnetos, with a comparison to Bosch magnets.
| Identifier | ExFiles\Box 4\5\ 05-page051 | |
| Date | 2nd November 1914 | |
| C O P Y. To Na.{Mr Nadin} from H.{Arthur M. Hanbury - Head Complaints} Copy to J.{Mr Johnson W.M.} Copy to Wor.{Arthur Wormald - General Works Manager} R6/IB21114. November 2nd. 1914. Re Magnetos. I was exceedingly interested in the description of the work done with reference to permanent magnets for the magneto machines. I shall be glad if you will send me further particulars when you send me the analysis of the Siebohm & Dieckstahl steel. I cannot understand why the first three steels refused to harden, as they appear to have had sufficient carbon in them, and the tungsten ought not to have stopped them hardening. They appear, however, to have been short of chromium, which may have had some influence. Whilst working at the matter, the magnets made from Siebohm & Dieckstahl's steel should be compared for permanency with the Bosch magnets. One way I should suggest to test the permanency of the magnets would be to arrange for two hollow coils of wire so that the magnet can be slipped in, and the coils subjected to a small current of electricity in a direction to demagnetise the magnets. The two specimens, that is, our make and the Bosch, could be inserted in these coils one after xxxxxx the other, and subjected to a small current to begin with, afterwards being increased in value until they were both demagnetised. The one having the | ||