| Title |
Mathematical Modeling : Modeling of the Bainite Transformation Kinetics in the CGHAZ of C - Mn - Mo - Ni Pressure Vessel Steel Weld |
| Authors |
엄상호(Sang Ho Uhm),서영대(Young Dae Seo),이경종(Kyung Jong Lee),이창희(Chang Hee Lee),김주학(Joo Hak Kim),홍준화(Jun Hwa Hong) |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Abstract |
A metallurgical model for the prediction of bainite transformation behaviors at coarsened grain heat affected zone(CGHAZ) was proposed. The isothermal transformation kinetics for the bainite which does not include incubation time was described by Johnson-Mehl-Avrami(JMA) equation and the $quot;ideal TTT$quot; diagram which depends only on the materials considered and characterizes the transformation independently of the experiment`s condition was introduced to predict the onset of transformation during continuous cooling conditions. And effects of prior austenite grain size on kinetic parameters of JMA equation were examined by isothermal transformation experiments. It was observed that the reaction rate was accelerated by increasing the grain size. Coupling Scheil`s rule of additivity, the model for predicting the volume fraction of bainite and hardness was developed. The reliability of the developed model was discussed by comparing the predicted data with measured one. |