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).
Tensile tests on two sample bars of Firth's Air Hardening Gear Steel from Cast No. T5122 and Cast No. T5647.
| Identifier | ExFiles\Box 52\2\ Scan005 | |
| Date | 24th October 1921 | |
| (1) F.R. 28A(100T) (S.G. 648, 19-2-20) G. {Mr Griffiths - Chief Accountant / Mr Gnapp} 2018 Rg. {Mr Rowledge} C. By. {R.W. Bailey - Chief Engineer} H15/24.10.21. Laboratory. Tensile Tests on two sample bars of Firth's Air Hardening Gear Steel from Cast No. T5122 and Cast No. T5647 (see Wdl/NJ1.10.21.) Of seven test bars cut from each of the above bars, one was tested in the "as received" condition, and the remaining six turned to a dia. of 0.580", given various heat-treatments as described below, and finally ground to the correct size, 0.564" dia. No. of Test Bar. Condition of the bar when tested. 1. "As received." 2. Cooled in air from 840°C. 3. " " and tempered at 250°C. 4. Cooled in air from 810°C. 5. " " and tempered at 250°C. 6. Cooled in air from 790°C. 7. " " and tempered at 250°C. No. 5. represents the treatment recommended by the manufacturers. | ||