화학공학소재연구정보센터
Materials Science Forum, Vol.503-504, 545-550, 2006
SPID-Induced nanocrystallization of shape memory Ni2MnGa-based and NiTi-based alloys quenched from liquid state
This paper describes the influence of severe plastic deformation (SPD) on the structure, phase transformations, and physical properties of melt-spun Ni2MnGa-based and NiTi-based shape memory alloys. It was found that the SPD by high pressure torsion (HPT) at room temperature can be effectively used for the synthesis of bulk nanostructured states in these initially amorphized or submicro-grained alloys obtained by melt-spinning method in the form of a ribbon. The subsequent low-temperature annealing of HPT-processed alloys leads to formation of homogeneous ultrafine nano-grained structure. This is connected with a very high degree and high homogeneity of deformation at SPD, in the whole volume of deformed sample.