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 degrees C in compression. Plastic flow is observed only above 800 degrees C when slip along (<1(2)over bar 10>) 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(<1(2)over bar 10>) gliding on (0001) basal planes are observed to dissociate into two identical partials with b=1/6(<1(2)over bar 10>) involving a stacking fault. High-resolution transmission electron microscopy of 1/3(<1(2)over bar 10>) dislocations indicates that basal slip in CrSi2 occurs through a synchroshear mechanism. (C) 1997 Elsevier Science S.A.