عنوان مقاله [English]
In this research, the effect of severe plastic deformation by high pressure torsion process on the microstructure, mechanical properties and pseudoelastic behavior of the Fe-10Ni-7Mn (wt.%) alloy after annealing at intercritical temperatures was investigated. The results revealed that applying high pressure torsion process for 20 turns on the solution annealed specimen and intercritical annealed samples at two different temperatures, 580 and 600°C for 2 hours, caused reasonable ductility with significant increase in micro-hardness, ultimate tensile strength and reduced grain size to nanometer. Phase evaluation by XRD and EBSD analysis showed that high pressure torsion process led to reverse transformation of martensite to austenite in solution annealed specimen and austenite to martensite transformation in the intercritical annealed samples. Among studied samples conducted in this research, the intercritical annealed sample at 600°C and subsequently deformed by high pressure torsion, revealed the most significant mechanical properties. Moreover, in this sample due to the higher fraction of austenite, fine grain size and high tensile strength, and easier reversible movement of the fcc/hcp interface, more amount of pseudoelasticity was achieved in comparison to the others samples.
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