Stacking fault shear (SFS) is the dominant creep deformation mechanism in Nibase superalloys subjected to primary creep conditions (750°C, 800MPa). TEM observations1 have shown that the source of plastic strain is the shearing of they' precipitates by dislocation ribbons with overall burgers vector of a< 112 >. SFS can only occur when they matrix is sufficiently saturated with a/2 < 110> dislocations. These matrix dislocations are unable to cut the y' because of the high energy APB they leave in their wake. By combining into a ribbon, shearing of the precipitates is facilitated by formation of intrinsic and extrinsic stacking faults (SISF and SESF).
|Number of pages||1|
|Publication status||Published - 17 Oct 2008|
|Event||Dislocations 2008: An international conference on the fundamentals of plastic deformation - Hong Kong Gold Coast Hotel, Hong Kong, Hong Kong|
Duration: 13 Oct 2008 → 17 Oct 2008
|Period||13/10/08 → 17/10/08|
- stacking fault shear
- creep conditions