低碳高铌钢Nb(C,N)奥氏体中沉淀析出理论研究

he precipitation kinetics of carbonitride niobium in austenite with various nucleation mechanisms, including homogeneous nucleation, nucleation at grain boundaries and nucleation at dislocations was calculated respectively. The calculation results showed that , in the case of non-deformation, the temperatures of maximum nucleation rate were 820℃, 780℃ and 1040℃, respectively, and the most rapid precipitation temperatures were 910℃, 900℃ and 1070℃, respectively, which were found to be undependant on whether the nucleation rate was constant or delined to zero rapidly. The effect of deformation stored energy within austenite on the precipitation kinetics was also calculated, and the results showed that deformation accelerated precipitation and reduced the critical nucleus size.