Texture and mechanical properties of EUROFER 97 steel processed by ECAP

The EUROFER 97 steel was processed by equal channel angular pressing (ECAP) at 550 °C for four passes via route C. The starting material consisted of ferrite–martensite dual phase composed by small subgrains of about 0.5 μm and low angle boundaries less than 5°. The volume fraction of second phase particles was around 10 vol.%, besides a texture formed by several fibers orientations belonging to the zone axes 〈1 1 0〉, 〈1 1 1〉 and 〈1 1 2〉. Increasing ECAP deformation, this microstructure became into equiaxed grain structures of less than 1 μm, and the misorientation between contiguous grains increased. This refinement of the microstructure was accompanied by the development of a new texture described by a family of fiber orientations related by rotations around axes 〈1 1 0〉 and 〈1 1 1〉. Tensile tests have revealed that an ECAP treatment at 550 °C for two passes could significantly strengthen the tempered material still maintaining good ductility.