Region of Research

In order to create the sound structures based on the next-generation manufacturing, the controlling factors and the causes of deterioration of the properties which obtained by welding and joining must be clarified, furthermore, it is necessary to establish the improvement technology of their properties. Almost all properties of weld metals or heat affected zones are closely related to their microstructures. In this department, the main research subjects are to reveal the microstructural formation mechanisms obtained by welding and joining through the understanding of solidification and transformation phenomena. Based on these findings, we develop the new microstructural controlling technology and the new improvement technology of their properties. Furthermore, we promote the applied research associated with the reliability evaluation, lifetime prediction and simulation of welding phenomena from the material scientific viewpoint.

Current Research Subjects

  1. Effect of solidification on microstructural formation and mechanical properties of high strength steel weld metal
  2. Analysis and simulation of peritectic reaction mechanism of steel during welding process
  3. Clarification of control factors on weld solidification cracking susceptibility of stainless steel
  4. Improvement of weld hot cracking resistance by using grain boundary engineered material
  5. Evaluation of environmental resistance and clarification of its influential factors of welds
  6. Development of optimization technology of microstructure and improvement of properties in duplex stainless steel welds
  7. Analysis of solidification and transformation behavior during welding process using laser high temperature microscope
  8. Prediction of ferrite morphology and properties in austenitic stainless steel weld metals
 

Prof.
H.Inoue
Assoc. Prof.
K.Kadoi
Assist. Prof.
S.Tokita

 
 
 




(a) High temperature in-situ observation system using laser microscope

(b) In-situ observation of structure morphology along weld cooling curve

(c) Microstructural change during solidification in the austenitic stainless steel weld metal obtained by liquid tin quenching method

(d) EBSD analysis for ferrite and austenite in austenitic stainless steel weld metal (ferrite and austenite grow independently in terms of crystallographic orientation during the solidification)

 
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