Volume 6, Issue 5
September 1984, pages 837-969
pp 837-899 September 1984
Echoing a recent remark by Prof. Ramaseshan, a perspective review is made of the field of phase transformation, highlighting areas that might appeal to physicists. Prominent in this category are the study of ground state structures, the study of phase diagrams and the study of kinetic phenomena.
Enumeration of ground state structures calls for inputs from group theory as well as reliable potentials, and physicists are therefore well equipped to make significant contributions. The theoretical analysis of phase diagrams (concerning which much experimental information already exists) raises challenging questions in equilibrium statistical mechanics. Since the problems map to Ising models of varying complexity and their generalizations, there are also very interesting connections to magnetism. Lately, computer simulation has added a new dimension, opening up fresh vistas both for theory and experiments. The study of kinetics belongs to the newly emerging area of non-equilibrium statistical mechanics. The focus being ontemporal phenomena, physicists can play a key role, particularly through the application of various types of relaxation spectroscopy. On the theoretical side too there are challenging problems, especially on account of the dominance of nonlinearities. Indeed if one is bold enough, one could even speculate on possible universalities underlying the complex microstructures invariably seen in late-stage evolution. In short, though the subject of phase transformations has thus far been nursed predominantly by metallurgists, there is enough room for physicists to make an independent entry and to make distinctive contributions.
pp 901-922 September 1984
The ushering in of the era of high technology in our country witnessed the emergence and growth of several new technologies which are either totally unconventional or less common in otherwise well known and established areas of industrial practice. A vivid example of the second category of advances is found in the development of extractive processes for obtaining the less common metals particularly required for service in nuclear, aerospace and electronics industries. In this paper, the growth of research and development in rare metals extraction in India is surveyed from its infancy in the fifties to the present stature of a firm footed technology accredited with several directed achievements and well-developed maturity.
pp 923-958 September 1984
The embryo of plutonium metallurgy in India, as well as in Asia, was formed nearly 25 years back in Trombay. Thereafter, in the intervening 25 years, significant amount of research and development work have been carried out atbarc on this man-made fissile element and indigenisation has been achieved in the fabrication, characterisation and property evaluation of plutonium metal, delta-stabilised alloys, Al-Pu fuels, Pu-Be neutron sources, (UPu)O2 fuels for thermal and fast reactors and (UPu)C and (UPu)N advanced fuels for liquid metal-cooled fast breeder reactors (lmfbr).
This paper summarises the development of plutonium metallurgy in India highlighting the safety aspects, our achievements and potential of plutonium for generation of nuclear electricity in the coming decades.
pp 959-969 September 1984
An overview of the studies of internal friction in hexagonal metals and alloys is presented. An outline of the experimental techniques of measurement and the atomistic mechanisms causing internal friction is also given.
Volume 42 | Issue 5
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