Nanostructured Materials by Twist Extrusion and High Pressure Torsion

Abstract

Microstructures of Fe-Cr-Ni and Fe-Mn alloys subjected to severe plastic deformation under pressure have been studied by high pressure torsion and twist extrusion. This processes have similar deformation schemes, but very different pressure levels. The paper shows that this has a dramatic effect on the value of the residual high pressure e-phase in Fe-Mn alloys that underwent severe plastic deformation using these methods. Under roughly the same equivalent deformation of 5-6 units, the value of the residual e-phase in HPT with 20 GPa pressure reaches 100%. In TE with 1.5 GPa, it does not exceed 50%.