Improvement of the techniques of manufacturing and processing of materials by high-level control of heat transfer

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The results for each of the sub-themes are as follows: (1) Fundamental flow and heat-transfer characteristics of the Marangoni convection, which is important in crystal growth under microgravity conditions, are studied. The criteria for onset of instability and the effect of magnetic field to damp the convective flow are-obtained. (2) Experiment is performed on directional solidification of A1-Cu alloys. Dependence of the metal structure on soliditication process is studied under different parameters controlling interfacial instability. Fundamental knowledge on the way of controlling the structure is obtained. (3) Molecular physicochemical mechanism of thin film formation by vapor deposition and the method of thermo-fluid-dynamic control are investigated using electron-beam heating. Various elements are vaporized and the dependence of the film growth rate on the state of gas-cluster and the thermo-fluid dynamic conditions are revealed. (4) Mechanism of film boiling around small solid s … More urfaces is investigated aiming at application to manufacturing of materials by rapid solidification utilizing vapor explosion. Some special features of the boiling mechanism and its feasibility to manufacturing process are made clear. (5) Effect of magnetic field on natural convection of liquid metal in a cubic container is studied theoretically and experimentally. It is found that a horizontal magnetic field perpendicular to vertical heating surfaces is much more effective than the magnetic field with different orientation. (6) Geometry of the anode is improved so that it may be cooled efficiently and the stability of plasma jet may be improved. Temperature history of the melt particle is clarified, and the performance characteristics are examined of the thermoelectric element manufactured by plasma processing. (7) Mechanism of generation of residual birefringence in the molded polymer is examined using optical visualization in order to obtain polymer plastic products of high quality. Relationship between the strain in the product and the cooling conditions is made clear. (8) Effective thermal conductivities of fiber-reinforced metals (FRM) are evaluated and the influencing factors are discussed. Methods of measurement of thermophysical properties suitable to FRM and fiber materials are discussed. Less