Prediction method of microstructres of Hot rolled plate during interpass time

摘要

PURPOSE: A method for predicting microstructure of hot rolled plate during interpass time is provided to appropriately control final physical properties of steel product ultimately by accurately prediction controlling the austenite state right before transformation by predicting recrystallization behavior during air cooling when rolling the plate. CONSTITUTION: The method for predicting microstructure of hot rolled plate during interpass time comprises a step(110) of predicting grain size of the hot rolled plate during heating by inputting constituents of the plate, heating temperature and time; a step(120) of predicting initial grain size of the hot rolled plate right after hot rolling considering rolling temperature, strain and strain rate; a step(140) of predicting recrystallization fraction of the hot rolled plate for static recrystallization; a step(150) of predicting grain growth of the hot rolled plate for the recrystallization completed hot rolled plate; and steps(160,170,180) of predicting average grain size of the hot rolled plate if the grain growth of the hot rolled plate is predicted, judging whether rolling operation in the following step is final pass or not, proceeding the initial grain size prediction step again if the rolling operation in the following step is not final pass, and terminating the rolling operation if the rolling operation in the following step is final pass so that the austenite state just before transformation is traced and predicted by applying the predicted information to all rolling passes after predicting recrystallization and grain growth during air cooling waiting time between respective rolling passes.