Hiroyuki Kokawa

  • Mechanism and phenomena during friction stir welding
  • Friction stir welding of high-softening-temperature materials
  • Development of novel materials by friction stir processing
  • Development of friction stir welding tools
  • Development of high performance materials by thermomechanical processing based on grain boundary engineering
  • Suppression of intergranular degradation of polycrystalline materials by grain boundary engineering
  • Microstructural evolution during ultrasonic welding of dissimilar metals
  • 3D additive manufacturing technology based on ultrasonic seam welding
  • Welding and joining
  • Grain boundary engineering
  • Friction stirring
  • Ultrasonic welding

We are studying welding and joining processes that are key technologies in the manufacturing industry. These processes are applied to a wide range of industrial areas including small electronic components and large
transportation structures, and are closely related to the performance and reliability of industrial products. Our group attempts to enhance the performance and reliability of the joints through understanding of the mechanism and fundamental phenomena during welding and joining processes based on the materials science.