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 report on samples of Firth's Air Hardening Gear Steel.
| Identifier | ExFiles\Box 52\2\ Scan003 | |
| Date | 4th October 1921 | |
| R R 402 (b H) (S H 828. 31-12-20) ROLLS-ROYCE LIMITED. LABORATORY. Y4429 c-to HY. {Tom Haldenby - Plant Engineer} Hs {Lord Ernest Hives - Chair} MICRO-EXAMINATION REPORT. DETAILS RE SPECIMEN. Date received..4.10.21. From..Firth's For..Samples for test. Micro Reference No. S.L38,139.& 140. Photomicrograph No. S..A135. to A140.(Incl). Photograph No......... Engine......... Name of Part ......... Piece No. .... Material. Firth's Air Hardening Gear Steel. Specification No......... Cast T5122. Thermal Treatment...Specimen No.138.-Hardened in air from 810°C. Specimen No. 139.-Hardened in air from 810°C and tempered from 250°C. (Recommended treatment.) Specimen No. 140.- As received. MECHANICAL TESTS. No. of Test Bar. Ult. Str. Y.P. Elong. % on 2" R.A. Brinell. Izod. Ft. Lbs. ..SEE REPORT ATTACHED. Stanton................ Blows................ Drop (4'5lb. Hammer.) Remarks................ ANALYSIS. Combined Carbon - - % Graphitic Carbon - - % Manganese .425 % Nickel 4.21 % Chromium - 1.21 % Cobalt - - % Vanadium - - % Silicon - - % | ||