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Controlling and analysis on materials properties and study on the mechanical and chemical processing for metals and composites

Mechanical and Chemical Processing for Metals and Composites

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Die surface morphology
controlled by shot-treatment:
Sliding property (a) good, (b) poor


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3D reconstructed image
of crack tip dislocations.


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Transverse cross sections
of multi-crystal silicon:
(a) as-etched surface,
(b) inverse pole figure,
(c) determination of twin boundary
and (d) grain boundary

The Course of Mechanical and Chemical Processing for Metals and Composites offers comprehensive education and research that covers the principles of materials forming processes, including plastic deformation, melt processing, material composition, and electrochemical surface modification, as well as the control and evaluation of material characteristics throughout the forming processes. (Deformation Engineering, Composite Engineering, Electrochemistry of Material Processing, Melt Processing, Surface Modification)

The service life of dies must be increased to enable the press forming of ultra-high tensile strength steels in manufacturing processes. We seek to enhance the lifetime and galling property of dies by creating an uneven surface and applying solid lubricants to die surfaces. Newly developed steels for use in automobile manufacturing will be enabled by innovations in the press forming process as well as by the enhanced properties of materials. Our research on galling properties is instrumental to the manufacture of ultra-high tensile steels.


Elucidating the fundamental mechanism behind the ductile-to-brittle transition
Body centered cubic (b.c.c) metals such as ferritic steels lose ductility at low temperatures, resulting in brittle fracture. This is referred to as a ductile-to-brittle transition (DBT). In order to enhance the reliability of those structure materials, it is necessary to understand the mechanism behind DBT behavior. Since the DBT is controlled by the motion of dislocations, which are lattice defects, we focused on dislocation activity in those materials. In order to understand the mechanism behind the ductile-to-brittle transition, we perform fracture tests with a macroscopic point of view and 3D analysis of dislocations by using advanced electron microscopy.

Solidification process conditions affect microstructure development and microscale phase selection, and eventually govern the functional and structural properties in metal, semiconductor and composite materials. For example, multi-crystal silicon is directionally solidified in order to array the crystal orientation and to increase its potential photoelectric transfer efficiency. Aluminum or magnesium cast alloys are used as parts in moving vehicles because the solidification process can produce a complex shape at low cost. Furthermore, the microstructural quality of the steel is determined during the directional solidification process. For these reasons, research into the solidification sequence is still needed to maintain the high quality of existing materials and to develop new materials.

In this laboratory, solidification mechanisms are analyzed in relation to mechanical and functional properties in metals (aluminum alloys, magnesium alloys for gravity casting and die-casting processes, steel and cast iron), semiconductors (multi-crystal silicon for solar batteries) and composite materials (alumina, silicon carbide reinforced aluminum alloy).

Professor Osamu Furukimi
Professor Hirofumi Miyahara
Associate Professor Masaki Tanaka
Assistant Professor Tatsuya Morikawa
Assistant Professor Masatoshi Aramaki
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