Effect of Finish Rolling Process on Improvement of Lamellar Tearing Resistance of High-Rise Building Steel

A process of finish rolling was researched to enhance lamellar tearing resistant of the high-rise building steel EH36. Experimental results indicate that gain size decreased with the decrease of finish temperature. When the finishing temperature on 840/810/780/750°C respectively, microstructure is finest with the size of 11.4μm. Moreover, the size of TiC precipitation turned ideal as the coiling temperature decreased. When coiling temperature is 550°C, the average size of TiC precipitation is only 0.09μm, refined by 40% relative to the conventional process. The microstructure and precipitation phase size of test steel are both effectively controlled because of the improved process. Therefore, high-rise building steel EH36 is finally prepared, and the lamellar tearing resistance reaches up to 78.2%.