Experimental evidence of liquid feeding during solidification of a steel

Sufficient liquid feeding under constrained solidification conditions like, those experienced in welding and casting, is vital to avoid solidification cracking. We present the results of unique in-situ experimental observations of liquid feeding in a solidifying steel melt pool. Liquid feeding was observed in the inter-cellular regions during the terminal stage of solidification. An average liquid flow speed of 450–500 μm s −1 was found. A pressure difference of the order of 10 4 Pa is calculated to cause the liquid flow. The rate of solidification shrinkage and the rate of deformation were found to be less than the rate of liquid feeding.