Effect of Cooling Process on Microstructure and Mechanical Properties of Hot Rolled TRIP Steels

The effects of cooling process after rolling on the microstructure and mechanical properties of hot rolled transformation-induced plasticity (TRIP) steels were investigated by means of optical microscopy, X-ray diffractometer, and tensile test machine. The results show that relaxation time had greater impact on the microstructure of hot rolled TRIP steels, the banded structure grade increased with relaxation time, at the same time, ferrite grain grew slightly. The hot rolled coiled TRIP steels had more retained austenite, as well as carbon content in retained austenite. The yield strength and elongation increased, tensile strength decreased with prolongating residence time in Bainite zone.