Assessment of local cracking susceptibility based on an in-situ observation

Abstract

In this study, solidification process of a hyperperitectic steel was in-situ observed by confocal scanning laser microscope (CSLM). By analyzing the solidification process, it is shown that the variation of solute concentration and the heterogeneous distribution of liquid phase may be the main reasons for the difference in the features of the peritectic reaction among the dendrites. Combining the whole experimental solidification process, it is found that the solidification sequence of the studied steel has been changed. Based on the experimental results, the rate of liquid feeding and the rate of solidification shrinkage were calculated by the modified Feurer's criterion. The calculation results were used to evaluate the local crack susceptibility during the solidification process. The predicted results show that the solidification process is safe, which is in good agreement with the experimental results.