Planar faults on (001) planes were formed during in situ annealing and straining experiments on MoSi2 single crystals in a high-voltage electron microscope. As-received and pre-deformed crystals grown by either the float-zone or Czochralski technique were exposed to temperatures of 400 to 1200C. The faults were only formed if dislocations with ½<111> Burgers vectors were present. The faults and the bordering partial dislocations were characterized by a transmission electron microscopy contrast analysis. The 2 partial dislocations bordering a fault had different types of Burgers vector. It was suggested that the faults resulted from a dissociation reaction according to: ½[111] = ½[110] + ½[001]; leading to intrinsic stacking faults on (001) planes. Similar microstructural mechanisms probably controlled both formation of the faults and the flow stress anomaly of the <111>{110} slip system.

Transmission Electron Microscopy Analysis of Planar Faults on (001) Planes in MoSi2 Single Crystals. S.Guder, M.Bartsch, U.Messerschmidt: Philosophical Magazine A, 2002, 82[14], 2737-54