HIGH-RESOLUTION ELECTRON-MICROSCOPY OF DISLOCATIONS IN A B2-TYPE INTERMETALLIC COMPOUND COTI

Core structures of edge and screw dislocations in CoTi were studied by high-resolution electron microscopy (HREM). An HREM image of an edge dislocation showed that the spreading of the dislocation core was limited within a distance of about 1.2 nm. From an HREM image of screw dislocations in CoTi, it was shown that the core was spreading on the (010) plane and the spreading of the core was limited within a distance of about 1.8 nm. It was suggested that the core spreading on the {010} plane, which was different from the slip plane of {110}, affected the abnormal temperature dependence of yield stress of CoTi.