Properties of Induction Reversion-Refined Microstructures of AISI 301LN under Monotonic, Cyclic and Rolling Deformation

In recent years, the efficient grain size refinement in austenitic stainless steels by the martensitic reversion process and the mechanical properties achieved in a laboratory-scale have been investigated extensively. In order to demonstrate the feasibility of this processing in an industrial-scale, a commercial 18Cr-7Ni-0.15N Type 301LN steel was cold rolled to various relative low thickness reductions (32-56%) to obtain 70-95% deformation induced martensite and subsequently annealed in an industrial-scale pilot induction line at the peak temperatures of 660820 degrees C. Some sheets were subsequently cold rolled 10-20% to compare the mechanical properties with those of the commercial strengthened grades. Results showed that the induction annealing at around 700 degrees C can produce reversed structures with much enhanced tensile and fatigue strengths compared to those of the commercial steel. The stability of the grain-refined austenite is lower than that in the commercial steel, but still cold rolling strengthening remains ineffective.