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).
Letter from Vickers Limited regarding the properties of their Cobalt Chrome Steel for use in permanent magnets.
| Identifier | ExFiles\Box 35\1\ scan 184 | |
| Date | 11th July 1922 | |
| X2713. X.2921. X.2713. SPECIAL MAGNET STEEL. Copy of letter received from :- VICKERS LIMITED, River Don Works, SHEFFIELD. Ref. GWV/HM{Capt. W. Hallam - Head Repairs}/NS{Norman Scott} 11th July, 1922. Dear Sirs, COBALT CHROME STEEL. "We have to thank you for your letter of the 10 th "inst relating to the above. "We have, for some considerable time now, manufactured "a Cobalt Steel for use with Permanent Magnets from which "exceptionally good results have been obtained. "The principal feature of this steel is the high "coercivity to be obtained, as you will note from a perusal "of curve No. XX111 enclosed herewith. "While of course it is possible to effect a considerable reduction in weight, in the use of this steel, "as against the ordinary Tungsten Magnet Steel, yet as a rule, "it is only possible to secure the fullest advantage from "its use by radical alterations in design. "Should you be interested we could arrange for an "expert to call upon you, or would be pleased to see one of "your representatives here, whichever you prefer. Yours faithfully, FOR VICKERS LIMITED, (sgd) W.G. Mann. From the particulars given on the photostat curve submitted, the coercive force of this steel is 270 and the remanence 10580, the product of the two being 1,169 x 10⁶. EFC. | ||