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).
Micro-examination and mechanical test report on cadmium-plated small screwed parts.
| Identifier | ExFiles\Box 30\6\ Scan065 | |
| Date | 13th December 1928 | |
| X 1360 Micro-Examination and Mechanical test Report. M631. By.{R.W. Bailey - Chief Engineer} Hll/EA13.12.28. Laboratory. c to Hs.{Lord Ernest Hives - Chair} Re Cadmium Plating on small Screwed Parts. Your Refs. BY/EM1/K.9.11.28. and BY16/G.9.11.28. The small screwed pieces submitted for test were treated as suggested in your first memo. The subsequent fracture and bend tests failed to show consistently any marked difference in ductility between :- (a) The unplated test pieces. (b) The cadmium plated test pieces. (c) The cadmium plated test pieces after treating at 150°C. Tensile tests were next made on a similar series of screwed rods. The results are given in table 1. It will be seen that the plating operation apparently does not affect the tenacity. Table 1. Actual Load in Tons. Test No.:- 1. 2. 3. 4. 5. 6. Average. Condition of material. As received 0.80 0.81 0.81 0.81 0.80 0.79 0.80 Plated. 0.78 0.80 0.83 0.89 0.86 0.83 0.83 Plated and Treated. 0.86 0.85 0.88 0.83 0.84 0.87 0.86 As the tensile tests did not indicate any brittleness, we reverted to the bend test, using a jig in which a dozen screwed rods could be bent simultaneously. Two further series of tests were made. In each series the rods were first tested in the "as received" condition. Then one set of test pieces was plated only, and the other set plated and treated at 150°C before again testing. The results are given below in tables 2 and 3 respectively :- Table 2. Angle at which Fracture commenced. Test Piece No. "As received". Cadmium Plated. 1 33° 380 2 33° 400 3 33° 400 4 33° 400 5 40° 400 6 40° 380 | ||