微波加热在矿冶方面的应用研究现状

介绍了微波加热技术目前在干燥矿物、磨矿、活性炭再生、矿物冶金等领域的国内外研究与应用现状。微波加热作为一种新兴的冶金技术越来越受到关注,随着微波加热技术的深入研究,微波技术在矿冶领域必将发挥重要的作用,具有广阔的应用前景。     

Superconductivity and physical metallurgy

After a brief summary of the historical development of the field of superconductivity and the background required for the topics treated in the present paper, some of the relationships between superconductivity and physical metallurgy are discussed. These are mainly in two areas: i) The distribution of magnetic flux in super conductors may show fine structures (boundaries between normal and superconducting regions in the intermediate state of type-I superconductors; quantized flux-lines in the Shubnikov phase of type-II superconductors) on such a scale that they interact strongly with the metallurgical microstructure of the superconducting materials, such as grain boundaries, dislocations, precipitates, and so forth. ii) Ideally, the flux-lines in a type-II superconductor form a two-dimensional lattice (Abrikosov lattice). The decoration technique of Träuble and Essmann has permitted the direct observation of these flux-lines lattices and has revealed that they contain a rather high density of defects. Most of them are known from the studies of defects in crystals, such as grain boundaries, dislocations, stacking faults, and vacancy and interstitial lines, but also disclinations, which were predicted by theory but have not yet been observed in metals, were investigated.     

Drops and bubbles in extractive metallurgy

Drops and bubbles are of great importance to the extractive metallurgist in his attempts to speed up processes by the use of sprays, foams, and jets. In this lecture the ways in which bubbles bring about mass transfer in liquid metals and in slag metal reactions are described. The role of interfacial turbulence is considered together with the effects of bubble size and frequency and the properties of the slag and metal phases. Reactions between drops of metal and flowing gases are analyzed in terms of mass transfer in the reacting phases and of chemical steps at the interface. Recent results obtained on reactions involving metal drops falling through liquids are considered in relation to mass transfer models in which internal circulation plays an important part. The work described reports only one facet of the rapidly developing subject of Process Engineering which ought now to feature prominently in metalurgical education. Dr. F. DENYS RICHARDSON. Professor of Extraction Metallurgy. Department of Metallurgy, Royal School of Mines. Imperial College of Science and Technology, London, England, graduated in chemistry at University College, London, in 1933, and obtained a Ph.D. in physical chemistry in 1936. From 1937 to 1939 he was Commonwealth Fund Fellow at the University of Princeton. From 1946 to 1950 he worked as superintendent chemist at BISRA, building up the work of the chemistry department. He went to Imperial College in 1950 to found the Nuffield Research Group in Extraction Metallurgy and advance the study of chemical metallurgy at high temperatures. He received awards in recognition of his work on the thermodynamic properties of high-temperature systems with special reference to iron- and steelmaking and for his work on high-temperature chemical metallurgy. He was appointed Professor of Extraction Metallurgy at Imperial College in 1957, his objectives there being to establish the department as a research center for chemical and process engineering metallurgy, and to develop a metallurgy course in which these subjects receive as much attention as physical metallurgy. In 1963 he was elected a Fellow of the Metallurgical Society of the AIME, and in 1964 he gave the AIME Howe Memorial Lecture. Professor Richardson delivered the Hatfield Memorial Lecture in 1964, the May Lecture of the Institute of Metals in 1965, and the Wernher Memorial Lecture of The Institution of Mining and Metallurgy in 1967. He was elected a Member of Council of the Iron and Steel Institute in 1967, having been an Honorary Member since 1962. In 1968 he became a Vice-President of the Institution of Mining and Metallurgy. In that year he was also elected a Fellow of the Royal Society and awarded the Bessemer Gold Medal of the Iron and Steel Institute, both honors for his contribution to the understanding of the thermodynamics and kinetics of metallurgical processes. In 1970 the honorary degree of Doktor-Ingenieur was conferred on him by the Technische Hochschale, Aachen. The 1971 Extractive Metallurgy Division Lecture, “Drops and Bubbles in Extractive Metallurgy.” was delivered on Wedresday, March 3, 1971.     

Metastable structures in metallurgy

Metastable structures or, more accurately, configurationally frozen metastable structures are no novelty in metallurgy. Indeed, much of the traditional practice of metallurgy has centered on the formation, characterization, understanding and control of structures which are either compositionally, topologically and/or morphologically metastable. However, in the past two to three decades we have seen a great upsurge in the production and study of new metastable structures in metallurgy, as well as in other condensed phase sciences. This upsurge reflects developments in the techniques of melt quenching, condensation and irradiation of materials, as well as in the kinetic understanding of structure evolution; and it has brought us nearer to making the concept of “ultramolecular engineering” viable. Among the new materials produced are glassy metals, highly super-saturated crystalline alloys and new alloys with exceptionally high interfacial densities. An overview of these new developments will be offered, following a discussion of the principles of metastable structure synthesis.