M Ramakrishna Rao
Articles written in Proceedings – Section A
Volume 43 Issue 6 June 1956 pp 359-367
Mineralogical compositions of five Indian clays have been determined by the petrographic, X-ray, electron-microscopic and differential thermal analysis methods. The relative importance of the methods is discussed and the procedures are described.
Volume 55 Issue 2 February 1962 pp 121-129
The mechanism of sub-microscopic precipitation in an Al-Zn-Mg alloy selected for its maximum response to ageing has been studied by a standardized oxide-replica technique in a 100 kV. Philips Electron Microscope. Contrary to earlier conclusions, examination of the oxide replicas has been shown to reveal details of the precipitation process almost as clearly as the thin-foil transmission technique. The reported formation of spherical Guinier-Preston zones followed by the development of a Widmanstaetten pattern of precipitated platelets has been confirmed. The zones have, however, been shown to grow into the platelets and