Region of Research

 Materials and joining technology make progress day by day, and natures of the joints that are created from them cannot be understood without close investigation of structures of the joint interfaces and the material structures. In order to achieve these purposes, Joint Interface Microstructure Analysis Room carries out observation of microstructure of joint interfaces and materials by transmission electron microscope (TEM) equipped with analysis functions, and supplies technologies for preparation of TEM specimen of dissimilar joint or composite materials etc. with focused ion-beam (FIB) and ion milling apparatuses.  Joint Interface Microstructure Analysis Room provides following services.
(1) Analyses of interfacial microstructures requested by staffs and joint researchers of the institute.
(2) Guidance and support for analysis and evaluation of results from TEM observation.
(3) Education of principles of TEM to students and joint researchers, and training of operations of TEM and associated apparatuses.
(4) Allover operations and maintenances of TEM and associated systems.
 And the room maintains and improves techniques for TEM observation of joint structures through independent study about metallographic study of dissimilar precise joining, etc. using TEM.

Current Research Subjects

  1. Application of anodic bonding to various metals
  2. Analysis of structure of various solid-state bonding intereface
  3. Glass/glass joining by anodic bonding

Reaction products that grew at joint interfaces between titanium and optical glasses. The bright-field image of BK7 crown glass/titanium joint interface by transmission electron microscopy (a), Selected Area electron Diffraction (SAD) pattern taken from the area indicated by a circle in the image a (b), bright-field image of FD110 dense flint glass/titanium joint interface (c), and SAD pattern taken from the area indicated by a circle in the image c (d). These reaction products were found to consist of α-TiO2. However, those forms are strongly affected by types of glass.

Distribution of retained austenite in 980 MPa high-tensile steel. (a) Bright-field image, (b) dark-field image taken by 111 reflection from austenite indicated in the diffraction pattern in (c), and (c)-(e) selected-area electron diffraction patterns taken from positions indicated in the bright -field image in (a). Austenite appears bright between ferrite laths in the dark-field image.

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