A new ultra-high strength steel with a fully austenitic microstructure and twinning-induced plasticity (TWIP) effect has been developed. TWIP gives this good combination of high over 1000 MPa ductility 35%. This chromium content, which increases its corrosion resistance. By combining cold rolling annealing, the achieved very fine an average grain diameter 2.85 µm. could be used for structural a...