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).
Analysis report on a broken rear axle from a Bentley, detailing its chemical composition, physical properties, and microstructure.
| Identifier | ExFiles\Box 89\5\ scan0082 | |
| Date | 28th March 1940 | |
| For the attention of:-- Mr. Howlett. re: Broken Rear Axle from Bentley. Analysis. Carbon .17% Nickel 3.92% Chromium .93% Physical Tests. Tensile Strength - 81.3 tons per sq. inch. Elongation - 17.3% Izod. - 44 ft. lbs. Brinell Hardness No.410. Microstructure. The structure of this shaft is fully sor-bitic, except there is slight ferrite banding, which suggests the steel should have been soaked rather longer prior to quenching. The Physical tests, however, are entirely satis-factory and the shaft should have withstood all normal usage. The fracture shows that breakage has not occurred suddenly but progressively. A previous sudden shock, or number of shocks, had caused cracks to form along the splines and these have gradually increased, weakening the metal until complete fracture took place. NP/AS. Laboratory. 28th March, 1940. | ||