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).
Metallurgical report detailing conclusions on the heat treatment and casting of aluminium pistons.
| Identifier | ExFiles\Box 76\3\ scan0005 | |
| Date | 18th September 1924 | |
| fabrication report - L52a contd. Page 2. Et. Heat-heating by reheating Aluminium piston metal to 550°C & quenching in water effects the microstructure helping to retain the copper in solid solution. The effect of this treatment on tensile Strength is to be tested. On examining pistons from the foundry it appears that a silvery sheen is still a satisfactory sign, indicating a close grain. The crown however is thicker & therefore is liable to cool slower & thus it has a dull surface when interior is bright. Conclusions - (i) Metal low in zinc. Iron & Silicon (ii) Cast at as low a temp. as possible (about 670°C) (iii) Cooled as rapidly as possible (a) by partial chilling (b) by stripping out of mould & then as soon as possible or dipping hot piston at 550°C (about) in water. [Signature] [Upside down text at bottom:] R.R. 936 A (400 T.) (S.C.) 19-5-16(C-1649) | ||