2012 年 52 巻 10 号 p. 1856-1861
The characteristics of the steel solidification in continuous casting, especially the peritectic reaction, have a considerable effect on the surface quality of the cast blanks. This study employed the FactSage software and thermodynamic calculation to determine the effects of various elements on the carbon content at the peritectic point (Cp) at equilibrium conditions for regular carbon and low alloy steels. For typical elements, we found that Cp=0.1763+0.0616[%Al]–2.5275[%S]+0.2652[%P]–0.0023[%Si]–0.0344[%Mn]+1.5250[%S][%Mn]–0.0210[%Si][%Mn]. Furthermore, the accuracy for the carbon content at the peritectic reaction was indirectly validated by comparing the liquidus, solidus and austenite formation temperatures from the calculated phase diagrams with literature data. Moreover, statistical analysis was performed on the longitudinal crack ratio for slabs produced in a commercial plant to determine the tendency for the peritectic reaction. The results show that when the cooling rate is taken into consideration, the difference between actual carbon content and predicted Cp is negatively correlated with the longitudinal crack rate.