Hydrogen Potential Sources in Refractory Materials during Steel Casting

It is well known that the presence of dissolved hydrogen in cast steel can cause defects that appear in hot rolling and forging of steel parts with heavy sections, and also contributes to the formation of internal cracks and blowholes during the solidification of the liquid steel. These problems are especially important in the continuous casting process. So, hydrogen levels must be kept at a minimum in this process. The aim of this work is to investigate possible sources of hydrogen, focusing on the materials that are in contact with the liquid steel during casting. The tundish refractory lining, shrouding tube, tundish covering agents, and casting powders were analysed. The results showed that not only the control of humidity content in those materials is critical, but the phase transformations that the materials suffer during the casting process are important as well.