Numerical Simulation of Solidification Structure Formation for a Large Flat Ingot during Water-cooled Mold Casting

There are some new water-cooled ingot caster were built in some steel plant in China for produce large flat ingot to meet the increasing requirement of the large ingot. While as the ingots become larger, there may cause many metallurgical imperfections, such as segregation, surface defects, etc. For predicting and investigating the quality of the large flat ingot casted by a new built water-cooled ingot caster, a numerical model is established to predict the solidification structure formation. Then the predictions are validated by comparing against metallographically measured results. The results show that the temperature decreases very quickly and keep the similar curves for different nodes on the surface of the cast. With the increase of pouring temperature, the columnar grain area is bigger. When pouring temperature is 1530 degrees C, ingot solidification organization mainly composed of fine crystal area and a wide range of internal equiaxed grains zone. The porosity is mainly formed in the top part of the ingot. The depth of the shrinkage porosity will deduce 31 mm when the casting temperature decreases to 1530 degrees C from 1550 degrees C.