PLASTIC-DEFORMATION OF TI3SN

Single crystals of Ti3Sn with the hexagonal D019 structure have been compressed at high temperatures in two orientations, close to [0001] and 40° from [0001]. In the latter orientation, deformation occurs by prismatic {1$00}<11$0) slip, indicating that the basal (0001)<11$0) slip is much less active than the prismatic slip. The critical resolved shear stress (CRSS) of the prismatic slip is about 40 MPa at room temperature and decreases gradually with increasing temperature. In the former orientation, deformation takes place by {11$1}<$26> slip below 1073 K, and by localized {$011}<11$3) slip above 1173 K accompanying a pronounced yield drop. The CRSS of the former pyramidal slip is as high as 600 MPa at room temperature and anomalously increases gradually with increasing temperature, whereas the lower yield stress of the latter pyramidal slip, which is strongly strain-rate sensitive, decreases rapidly with increasing temperature. Polycrystalline specimens with large columnar grains have also been tested, and the obtained results are in between those of single crystals of the above two orientations. © 1990, The Japan Institute of Metals. All rights reserved.