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).
Laboratory memo on corrosion tests for radiator tubes, comparing electrolytic copper, copper with arsenic, and brass.
| Identifier | ExFiles\Box 38\2\ Scan117 | |
| Date | 1st August 1920 | |
| H.B. / BY.{R.W. Bailey - Chief Engineer} S.E.P. X.3456 HL12/EB11. 8. 20. Laboratory. X 8456 RE RADIATOR TUBES. X 3678 Some corrosion tests we did two years ago indicated that electrolytic copper was more resistent to alkaline water in the form of .1% sodium Hydrate than copper containing a considerable amount of arsenic (this in the presence of a piece of iron). We conclude that copper containing about .4% arsenic would be used for the radiator tubes in America if it were found that brass tubes would not stand up to local water. Brass, according to some recent corrosion tests that have been running for over a year, is less acted on by a salt solution or sea water than copper containing a small quantity of arsenic. Nearly similar in behaviour in .1% sodium hydrate, slightly more acted on in the presence of .1% sodium carbonate, slightly less acted on by .1% sulphuric acid, neither are seriously acted on by Derby tap water nor distilled water, though the iron with which they were immersed had nearly rusted away. From the above, it does not appear very likely that there should be much trouble with brass tubes, if of a reasonable composition, and this is confirmed by the tests we referred to in our note H13/EB5. 8. 20 which on continuation indicated that the alkaline solutions did not produce damage in the way of pitting, but only caused a thin skin type of oxidation which is quite normal. We should be interested to know the composition Contd | ||