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).
Letter from Thos. Firth & Sons, Ltd. regarding the supply of rustless steel for brake levers, with chemical analysis and physical properties.
| Identifier | ExFiles\Box 75\5\ scan0006 | |
| Date | 4th October 1923 | |
| Copy of letter from:- Works Manager's Office, Steel Works, Tinsley. to:- Mr G.E. Wolstenholme. Ref. JWF/AC. THOS.FIRTH & SONS,LTD., Norfolk Works., SHEFFIELD. 4th October.1923. Dear Mr Wolstenholme., I have this morning had a copy of Messrs. Rolls Royce letter of October 2nd, in connection with the supply of rustless steel for brake levers. As you are visiting them tomorrow I think it advisable that you should know my opinion of such a steel for the purpose; Firstly in looking at the Specification it appears to me as if this has emanated from America as the physical properties are mentioned in pounds. Dealing with the physical properties specified, I very much doubt, in fact I am nearly certain, that you would not obtain the elastic limit with the analysis specified unless the material was severely cold worked. As a guide I give you a test which was carried out on somewhat similar steel in the water quenched condition;- ANALYSIS. Car. Mn. Si. Ni. Cr.{Mr Cra???ster / Mr Chichester} .52 1.09 .40 25.45 2.0 PHYSICAL PROPERTIES. Elastic limit................ 12.9 tons/sq.in. Yield point.................. 19.6 " " Maximum Stress............... 48.2 " " Elongation................... 51.5 per cent. Reduction of Area............ 67.8 Brinell...................... 175 It will be noted that this steel differs slightly from that specified, in that the Manganese is higher and the Chromium lower, and I should not anticipate that in raising the Chromium and reducing the Manganese it would lift up the elastic limit, without the cold working, to anything like 60% of the ultimate stress. contd. | ||