Martensite reversion and texture formation in 17Mn-0.06C TRIP/TWIP steel after hot cold rolling and annealing

Abstract

High Mn steels with Si and Al present great plasticity when deformed due to the TRIP/TWIP effect. This work evaluated the microstructural evolution and texture formation of a 17Mn-0.06C steel after hot rolling, cold rolling to 45% of thickness reduction and annealing at 700 °C for different times. The microstructural analysis was performed by means of dilatometry, X-ray diffraction (XRD), optical (OM) and scanning electron microscopy (SEM), electron backscattering diffraction EBSD and transmission electron microscopy (TEM). It was found that during the cooling process, after the steel is annealed, the athermal ɛ and α′ martensites are formed. Tensile test results showed that the steel exhibits yield and tensile strength around 650 and 950 MPa with a total elongation around 45%. The austenite texture contains brass, copper and Goss components while the α′ and ɛ martensites textures contain rotated cube and prismatic and pyramidal fibers, respectively.