Design of a FeMnAlC steel with TWIP effect and evaluation of its tensile and fatigue properties

The present study evaluated the mechanical properties in monotonic and cyclic stress of a FeMnAlC steel designed by thermodynamic calculations with predicted stacking fault energy values within Twinning Induced Plasticity (TWIP) effect actuation range. The material was processed by spray forming, using recycled feedstock from structural steel and aluminum engine block. The deposit was mechanically formed by rotary swaging and subsequently annealed. This processing route resulted in a single-phase austenitic material with minimal texture. The steel presented nanotwinning deformation during the monotonic test and an elongation at fracture of 73%. The fatigue limit was determined by the staircase method, and deformation twins were also nucleated during the cyclic straining in the surface specimen and in the fatigue crack propagation path. •The Fe-25Mn-3Al-0.4C steel was designed to be fully austenitic with TWIP effect.•Using spray forming, swaging and annealing, fully austenitic homogeneous microstructure with low texture level was obtained.•High ductility and a high density of mechanical twins was obtained after tensile tests.•Nanotwins also nucleated under cyclic loading throughout the crack path.