Effect of coiling temperature on retained austenite and mechanical properties of hot rolled TRIP steel

In order to study the effect of coiling temperature on the retained austenite and mechanical properties of hot rolled transformation-induced plasticity(TRIP) steel,the hot rolled TRIP steel prepared at three different coiling temperatures was analyzed with the optical microscope(OM),scanning electron microscope(SEM),X-ray diffractometer and tensile tester.The results show that with decreasing the coiling temperature,the grain size of retained austenite decreases,and the volume fraction as well as the carbon content of retained austenite also reduces.The circularity of retained austenite in hot rolled TRIP steel prepared at both 450 ℃and 400 ℃ has no obvious difference.However,the retained austenite in hot rolled TRIP steel prepared at 350 ℃ shows better circularity.With decreasing the coiling temperature,the hot rolled TRIP steel exhibits high yield strength and low elongation.The hot rolled TRIP steel prepared at 450 ℃ possesses the optimum comprehensive mechanical properties.