Dislocation Arrangement in Compressed FeAl Single Crystals

抄録

The dislocation arrangement in FeAl single crystals compressed at 77, 300 and 473 K has been investigated on the operated (\bar211), (\bar101) and (\bar1\bar12) slip planes by transmission electron microscopy. It is shown that the isotropic invisibility criterion is not applicable to FeAl whose elastic anisotropic factor is larger than that of α-iron but less than NiAl. The observed dislocation arrangement in FeAl strongly depends on the slip planes and the deformation temperature. In the crystals deformed in the [111] antitwinning direction on a (\bar1\bar12) plane, straight, long, screw dislocations are predominant at 77 K and very wavy shape dislocations are seen at 300 K, whereas in the [111] twinning direction on the (\bar211) plane numerous long edge dislocations in irregular shapes are seen besides straight screw dislocations at 77 K and these edge dislocations are still observed in the crystals compressed at 473 K. In the crystals deformed on the (\bar101) [111] slip system, only mixed dislocations are observed.