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 corrosion resistance of chromate-coated Elektron metal when exposed to various fuels with and without water.
| Identifier | ExFiles\Box 27a\4\ Scan170 | |
| Date | 21th July 1933 guessed | |
| REPORT ON THE CORROSION OF CHROMATE COATED ELEKTRON METAL ---------- In Report No. 26, dated June 1932, there were presented the results of some experiments with Elektron metal, Duralumin, and aluminum in which the metals were exposed to various gasolines, with and without water, and were examined for corrosion. Briefly, the results showed that (a) dry ordinary gasoline, dry Ethyl Gasoline, and dry benzol have no corrosive effect on any of the metals; (b) in the presence of water and any of the fuels, the Elektron metal corrodes, the corrosion being greater with Ethyl Gasoline than with the other fuels. Recently a sample of Elektron metal coating by dipping in acid sodium bichromate solution was submitted by the Aluminum Company of America for corrosion tests. These tests were carried out as follows:- strips of the metal one-half inch wide and four inches long were placed in glass test tubes and were allowed to stand for six weeks at room temperature in contact with gasoline, or benzol, with and without an equal amount of water. Control experiments were carried out with ordinary Elektron metal and with Duralumin. The results of the tests may be summarized as follows: (a) Neither ordinary gasoline, Ethyl Gasoline, or benzol had any visible effect on the coated or uncoated metal in the absence of water. (b) In the presence of water, the part of the coated Elektron metal which dipped into the water was darkened in color with all fuels tested, but there was no evidence of appreciable corrosion, and no difference observable between the sample in Ethyl Gasoline and in ordinary gasoline. The uncoated Elektron metal was corroded in all cases, but more extensively with Ethyl Gasoline and water than with the other fuels. The Duralumin dipping into the water was somewhat discolored, but there was no appreciable evidence of corrosion, except for a very slight amount in the case of the benzol. Conclusions. Elektron metal treated with chromate solution is apparently far superior to uncoated Elektron metal in resistance to corrosion in the presence of water. It appears to be approximately the equivalent of Duralumin in this respect. GRAHAM EDGAR | ||