Transmission electron microscopy study of the microstructure and dislocation configuration in Al₆₇Co₈Ti₂₅

Abstract

The microstructure and dislocation configuration of the Al₆₇Co₈Ti₂₅ intermetallic compound were observed and studied by transmission electron microscopy. It was shown that the matrix of the alloy with nominal composition Al₆₇Co₈Ti₂₅ had the L1₂ crystal structure, and a small amount of second phase present in part of the grain boundaries was identified to be TiAl₂Co. Two types of dislocation were observed to exist in this alloy: 〈101〉-type superdislocations and 〈100〉-type ordinary dislocations. The former were frequently observed to dissociate into partials bounding some planar faults, while 〈100〉 dislocations were usually single dislocations or dislocations in a dislocation row.