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).
Composition of ballast resistance wire and a request to query suppliers for an improved alloy.
| Identifier | ExFiles\Box 168a\5\ img004 | |
| Date | 19th June 1926 | |
| To Wd.{Mr Wood/Mr Whitehead} from EFC. X 8790 EFC1/T19.6.26. RE BALLAST RESISTANCE WIRE. X 3716 The ballast resistance wire which we are at present receiving for production shows on analysis to be nearly pure nickel and only to contain 0.20% of iron. This is satisfactory if we specify pure nickel. We have now, however, reason to believe that a small content manganese, about .3 to .4%, improves the ballast resistance properties of the material, and we are desirous of obtaining some nickel wire with approximately this content of manganese, but still with as low as possible a content of iron. We should be pleased if you would put a query to our suppliers as to whether they could supply us with sufficient wire for, say, 1 dozen ballast resistances, alloyed with manganese in the manner referred to; standard diameter. EFC. | ||