Abstract

Two duplex stainless steels with difícrent austenite particle distribution inside the ferrite matrix were deformed by torsion at high temperatures. Two different flow curve shapes were observed. Type 1 indicated that. after rapid loading, the stress rose by fin extended linear región, which dropped alter overcomíng stress peak. The type II flow curves showed a very fast stress increase during loading, after which the curves displayed extensive work hardening and softening regións. The microstructural evolution was observed which indicated several differences, However, the most signifícant finding was the presence of small particles of austenite with a Widmannsttäten-like structure inside the ferrite in simples that showed the type II flow curves.