Deformation of single-crystal Mn 3Sn

Abstract

Single-crystal Mn 3Sn was chosen to investigate the behavior of a DO 19 intermetallic compound. The alloy of composition 23.75 at.% Sn was made from the pure elemental materials and single crystals were grown using the Bridgman process. Compression samples were prepared using an electric discharge machine and tested at moderate strain rates in an air or argon environment, depending upon the test temperature. Testing temperatures ranged from 77 to 1200 K and various orientations within the standard unit triangle were chosen so as to produce slip on several slip systems. Preliminary results show that the dominant mode of deformation is basal slip accompanied by an anomalous flow stress vs. temperatures behavior. There was, however, also some prismatic and pyramidal slip observed. For most orientations slip traces were observed on the sample surfaces; however, for some orientations with low Schmid factors, local crushing or even brittle fracture were observed.