Effect of high speed high pressure torsion parameters on grain refinement of coned shape Fe based SMA active elements

High Speed High Pressure Torsion (HS-HPT) refers to processing that involves a combination of high pressure with torsional straining. This technique allows the efficient grain refinement on shape memory alloy brittle (CuAlNi) or with very low plasticity (FeMnSiCr). HS-HPT involve slippage between anvils and sample this means the SPD occurs at specific temperature. The recrystallization during HS-HPT on shape memory alloys determines their functionality without supplemental heat treatments. The samples manufactured by HS-HPT are discs, rings or coned shaped, 20-40 mm in diameter and 1mm - 0.2 mm thickness. Varying HS-HPT parameters coned shaped elements with increasing deformation degree were produced from Fe28Mn6Si7Cr [ mass %] shape memory alloy. Scanning electron microscopy (SEM) observations, highlighted ultrafine structure. Experiments show that the mechanical properties of the alloy can be enhanced by HS-HPT. (C) 2015 The Authors. Published by Elsevier Ltd.