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

Abstract:

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 660–820 °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 °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.

• Periodical: Materials Science Forum (Volume 941)
• Pages: 601-607
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.941.601
• Online since: December 2018
• Authors: Antti Järvenpää*, Matias Jaskari, Pentti Karjalainen
• Keywords: Austenite Stability, Austenitic Stainless Steel, Induction Annealing, Refined Grain Size, Tensile Properties

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