Plastic deformation of single crystals of CrSi2 with the C40 structure

The deformation behavior of single crystals of CrSi2 with the C40 structure has been investigated as a function of crystal orientation in the temperature range from room temperature to 1400°C in compression. Plastic flow is observed only above 800°C when slip along 〈1210〉 on (0001) is operative and no other slip systems are observed in the whole temperature range investigated. The critical resolved shear stress (CRSS) for basal slip decreases rapidly with increasing temperature. Dislocations with b=1/3〈1210〉 gliding on (0001) basal planes are observed to dissociate into two identical partials with b=1/6〈1210〉 involving a stacking fault. High-resolution transmission electron microscopy of 1/3〈1210〉 dislocations indicates that basal slip in CrSi2 occurs through a synchroshear mechanism.