Quantitative Research on Dissolving of Nb in High Nb Microalloyed Steels during Reheating

The accurate prediction of soluble Nb content during reheating is helpful for the design of chemical composition and reheating parameters for Nb-containing steels. The dissolution behavior of Nb in high Nb microalloyed steels was investigated. The results show that Nb does not entirely dissolve for high Nb microalloyed steels containing Ti after holding at 1300 °C for 3 h. The soluble Nb content increases with the decrease of C content and/or the increase of Nb content in steels. Moreover, an expression has been established to describe the amount evolution of soluble Nb in high Nb microalloyed steels during reheating and the validity of this expression has also been verified by experiment.