In-situ investigation of the solidification of low-alloy steels

A major issue during the production of large steel ingots is the formation of segregated areas that are linked to the microstructure and convective flow development during the solidification step. The aim of the proposed experiments is to investigate the solidification path and dendritic microstructure formation during the solidification of low-alloy steels. The originality of the experiments consists of directly visualizing the microstructure formation. Directional solidification experiments will be monitored in-situ with a unique high-temperature furnace allowing synchrotron radiography to be used. Particular emphasis will be placed on the characterisation of the dendritic morphology evolution with regard to the peritectic reaction/transformation. The ultimate aim is to improve the description of the mushy zone permeability, which is a key parameter for the formation of macro-segregation in large steel ingots.