NON-NORMALIZED STEEL WITH AN ULTRAFINE GRAINED PEARLITE STRUCTURE AND A PREPARATION METHOD THEREOF EMPLOYING CONTROLLED COOLING PROCESSES TO OBTAIN HIGH STRENGTH AND HIGH TOUGHNESS

摘要

PURPOSE: Non-normalized steel with an ultrafine grained pearlite structure and a preparation method thereof are provided to obtain an ultrafine grained colony and lamella structure by restricting ferrite transformation and continuous cooling pearlite transformation and inducing low-temperature pearlite.;CONSTITUTION: A method for preparing non-normalized steel with an ultrafine grained pearlite structure comprises the steps of: compressing a steel material at high temperatures, rapidly cooling the hot-forged body to a low-temperature pearlite transformation range, maintaining the super-cooled hot-forged body at a constant temperature in the low-temperature pearlite transformation range, and air-cooling the hot-forged body.;COPYRIGHT KIPO 2013