Super Plasticity of /α Duplex Stainless Steels

Document Type: Persian


1 Assistant Professor, Young Researchers and Elite Club, Islamic Azad University, Khomeinishahr Branch, Isfahan/Khomeinishahr, Iran

2 MSc Student, Department of Mechanical Engineering, Khomeinishahr Branch, Islamic Azad University, Isfahan, Iran.


In this paper the studies of the two-phase super Plasticity stainless steels is studied. The aim of this study obtained the suitable criteria to thermo-mechanical treatment condition for decrease the microstructure (grain size) and super plasticity property in two-phase stainless steels. Also here we want to show the appropriate ranges of temperature and strain rate used in the process super plasticity to obtain maximum elongation for this kind of steel. The results showed that by using thermo-mechanical treatment that consists of dissolving, rolling and annealing, the grain size can be achieved to 0.5-4 μm.
The maximum elongation is achieved 1000% in the temperature range 800-1000˚C and strain rate is achieved 0.01-0.1 s-1. Under these conditions, the sensitivity coefficient of strain rate is around 0.6

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