Method for Predicting Mechanical Properties of Hot-rolled and Cooled Steel

摘要

PURPOSE: A method for predicting mechanical properties of steel rolled and cooled is provided which is capable of controlling physical properties of final microstructure by accurately measuring transformation behavior even if cooling rate is changed during cooling of the rolled steel after rolling steel. CONSTITUTION: The method comprises a step of obtaining a transformation amount (X1) during air cooling of steel to be cooled after rolling; a step of obtaining a transformation amount (X2) during water cooling of steel to be cooled after rolling; a step of obtaining grain diameter of ferrite transformed during air cooling and water cooling; a step of obtaining an average grain diameter from the obtained ferrite grain diameter; and a step of obtaining tensile strength and yield strength of the steel from hardness obtained from an average transformation temperature and the average ferrite grain diameter.