| Stainless steel 304 and 316 are mostly used as the structural materials for light water reactors and stainless steel is also a potential candidate material for future generation reactors. As an attempt to enhance the mechanical properties and irradiation resistance of the stainless steel, severe plastic deformation techniques like high pressure torsion (HPT) and equal channel angular pressing (ECAP) has been used to refine the grain size and increase grain boundary volume. Microstructure of these pre-irradiated steels have been characterized through transmission electron microscopy, scanning electron microscopy, X-ray diffraction, energy dispersive spectroscopy and microhardness testing. Annealing was carried out in different temperature and time to find out the thermal stability of these steel. Here in this research, an attempt has been made to investigate how HPT and ECAP process changed the microstructure to result in better mechanical properties and how stable they are in elevated temperature for a prolonged period.
Key Words: SPD, ECAP, HPT, TEM, SEM, XRD, Thermal Stability. |