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).
Results of stress, hardness, and impact tests on various metal test bars.
| Identifier | ExFiles\Box 154a\1\ scan0102 | |
| Date | 10th November 1928 guessed | |
| 2. Table II. Test Bar No. Ult. Stress. Yield Point. Elong. % on 2" R.A.% Brinell Hardness. FD {Frank Dodd - Bodies} 1 61.8 52.0 7.5 19.8 293 FD {Frank Dodd - Bodies} 2 61.2 48.6 8.0 15.0 293 FD {Frank Dodd - Bodies} 3 63.5 52.0 10.0 19.5 293 The case on these bars showed signs of exceptional brittleness, not only cracking transversely in numerous places, as would be expected with a thin case, but also disintegrating on the surface and throwing off quantities of small particles and flakes in all directions. Carburised nickel steel to specification 2071A does not disintegrate on the surface in this manner whether the case is thin or thick. The test figures in Table III were obtained on bars which had been fully treated and nitrogenised, and had then been ground in order to remove the case before testing. Table III. Test Bar No. Ult. Stress. Yield Point. Elong. % on 2" R.A. %. Brinell Hardness. FD {Frank Dodd - Bodies} 4 62.5 54.0 19.0 60.0 285 FD {Frank Dodd - Bodies} 5 59.0 49.0 20.0 53.5 285 FD {Frank Dodd - Bodies} 6 63.1 53.2 20.0 60.0 293 Stanton Tests. The figures given in Table IV were obtained on fully treated and nitrogenised bars. In accordance with your instructions the notch was cut before case-hardening and therefore this part of the bar carried a case when tested. The usual hammer fall of 2 inches was employed. Table IV. Test Bar. No. No. of Blows. (Corrected). Brinell Hardness on Core. FD {Frank Dodd - Bodies} 13 6181 262 FD {Frank Dodd - Bodies} 14 6471 269 FD {Frank Dodd - Bodies} 15 6183 269 FD {Frank Dodd - Bodies} 16 6274 269 Upton Lewis Tests. The figures given in Table V were obtained on bars fully treated and case-hardened. The throw employed for these tests was 1¼", the jaw separation 1", and the diameter of the bars 0.500". | ||