Dislocation motion in erbia single crystals

Dislocation motion during high-temperature deformation of erbia single crystals has been investigated. Compressive deformation along [111], [1̄1̄2], [1̄10] and [123] at 1640°C resulted in slip on {110} planes. The Burgers vector was determined to be b→=12〈11̄1〉. Dislocations with such a large Burgers vector (9.1 Å), can dissociate into 14〈11̄0〉 and 14〈11̄2〉 partials. The critical resolved shear stress of the samples at 1640°C was estimated to be ≈38 MPa. Cleavage at room temperature was found to be on {111} planes.