1. National Engineering Research Center for Advanced Rolling Technology, University of Science and Technology Beijing, Beijing 100083, China;2. Technology Centre, Anshan Iron and Steel Group Co., Anshan 114009, Liaoning, China)
Abstract:The retained austenite and its stability of transformation induced plasticity (TRIP) steel after isothermal bainitic transformation were investigated using SEM, TEM and XRD. The results showed that the amount of retained austenite is increased with increase of temperature or holding time of isothermal bainitic treatment in the range of 400440 ℃ and 120300 s respectively. At the same time the carbon content of retained austenite is decreased. It was found that the retained austenite is occurred in the forms of relative large particles, thin film and small globular particles. Obviously large retained austenite is unstable,thin film is more stable and fine globular particles are most stable.The combined formability of TRIP steel is deteriorated due to insufficient amount of retained austenite or reduced carbon content in retained austenite caused by excessive amount of retained austenite.Besides, the decrease of carbon content in retained austenite,caused by formation of cementite during extralong isothermal bainitic treatment makes stability of retained austenite reduced.
江海涛;唐荻;刘强;刘仁东;严玲. TRIP钢中残余奥氏体及其稳定性的研究[J]. 钢铁, 2007, 42(8): 60-0.
IANG Haitao;TANG Di;LIU Qiang;LIU Rendong;YAN Ling. Investigation of Retained Austenite and Its Stability in TRIP Steel. Iron and Steel, 2007, 42(8): 60-0.