Effect of Finishing Rolling Temperature on Microstructure and Mechanical Properties of Q460GJC Steel for Building

The final rolling of Q460GJC steel at different temperatures was simulated by Gleeble-3500 testing machine, the effects of different finishing temperatures on the microstructure and properties of Q460GJC steel were studied by OM, SEM, and tensile tests.The results show that with the increase of finishing rolling temperature, the yield strength of Q460GJC steel decreases gradually, the overall tensile strength changes little, and the yield strength ratio decreases continuously. The yield ratio of Q460GJC steel rolled at 860℃is the lowest, which is 0.72, and its yield strength and tensile strength are 477.5 MPa and 663.1 MPa respectively. With the increase of finishing rolling temperature, the size and quantity of M/A island in Q460GJC steel gradually decrease, the morphology gradually changes from block to fine strip, and the distribution is more uniform.