In-situ Observation of Microstructure Formation Process of Weld Metals by Time-resolved X-ray Diffraction

Abstract

In-situ characterization of directional solidification process during welding was carried out using utilizing intense synchrotron radiation. Then, behaviors of dendrites in steels during welding of a practical manufacturing process were investigated using time-resolved X-ray diffraction with the uniquely-sensitive two-dimensional pixel detector. Consequently, the crystal growth during rapid cooling was caught in detail by a systematic peak profile analysis in order to acquire the essential information for controlling the weld microstructure. Our results would suggest the possibility of rotation of dendrites in high alloys and fraction of maximum of shrinkage is corresponded to thermal expand coefficient of low alloy in directional solidification during rapid cooling.