Phase Transformations and Physical Properties of New Materials - An Approach using New Techniques -

点击翻译按钮获取中文摘要

In this project, we studied various phase transformations by using new approach, by aiming the creation of new materials. The new approach has two aspects ; the first is new ideas and the second is the utilization of new experimental techniques. In practice, the project was divided into 6 groups in the following, and close co-operation was held between the groups. (1) Phase transformation (PT) and physical properties (PP) in intermetallics, (2) PT and PP in ceramics, (3) PT and PP in shape memory alloys, (4) Structure and PT in quasicrystals and amorphous materials, (5) First order PT study by synchrotron radiations, and (6) PT studies by computer simulations. The results of these studies were intensively discussed at Nagasaki (Dec. 11-13, 1992) and at Ishikawa (Jan. 6-8, 1994).Through these intensive discussions, many symptoms appeared for the new development of phase transformation studies. For example, a statistical mechanical approach which unifies the athermal and the isothermal martensitic transformations, the observation of incubation period in the athermal transformation, for which the incubation period was belived to be absent, the clarification of the relation between a quasicrystal and a nearcrystal, PT under high pressure, the structure determination of a new type "Zeolite" and PP (observation of ferromagnetisim in K trapped in the cages), and quite successful application of synchrotron radiation and high resolution electron microscopy, etc. The above are only a few among many useful results, which are published as a report for the present projext. I beleved these results make great contribution to the further development of phase transformation studies.