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).
Properties and potential applications of Nitro Alloy Steel compared to standard steels.
| Identifier | ExFiles\Box 154a\1\ scan0112 | |
| Date | 16th November 1928 | |
| R. {Sir Henry Royce} c. Wor. {Arthur Wormald - General Works Manager} c. Rg. {Mr Rowledge} c. Hs. {Lord Ernest Hives - Chair} c. Hl. ----------------- 44469 BY5/G.16.11.28. NITRO ALLOY STEEL. ----------------- I consider the information circulated in Hll/EA.10.11.28. when compared with similar physical tests where they are available, show that the present type of nitrogen hardening steel arrived at by the addition of molybdenum makes the steel useful in quite a number of spheres. I am attaching hereto comparisons of physical tests made between our present standard steels and the nitrogen hardening type. These figures show distinctly that the new material is likely to be a very satisfactory proposal. I would like to remark that under the heading of the Upton Lewis test, where the steel does not appear to show up as well, that the reason for this is the only comparable figures are those taken on road spring steel in its spring tempered condition, whereas the nitro alloy is in crankshaft tempered condition, the brinells being roughly 400 for the road springs, and 302 for the nitro alloy (crankshaft). With reference to the comparisons made between our present type of case hardening steel and nitro alloy, the results are what we should expect. I do not for a moment consider that the nitro alloy steel will replace the case hardening type of nickel steel, but represents possibilities in the direction where case hardening steel is :- a {Mr Adams} /- Either not sufficiently high in hardness b/- or Is not possible owing to the complicated nature of the part. In any material which has a hardness comparable with the iron nitride of the nitrogen hardening steel, it is impossible to make an indent, the only possible effect that I can see could be arrived at is a splintering of the surface if anything in the form of an indentation is produced. What it means is that the steel is not useful under such conditions, but it has a large field of possibilities where such conditions need not arise. BY. {R.W. Bailey - Chief Engineer} 131 | ||