Mechanical properties and determination of slip systems of the B2 YZn intermetallic compound Original Research Article

Single crystal specimens of YZn (B2) were tested in tension at room temperature. Specimens with a [1 0 1] tensile axis orientation exhibited {0 1 1}〈1 0 0〉 primary slip and an ultimate tensile strength of 365 MPa at 3.7% elongation. Specimens with [0 0 1] and [1 1 1] tensile axis orientations showed no slip lines and fractured at a stress of 180 MPa at 3.3% and 130 MPa at 2.9% elongation, respectively. Transmission electron microscopy (TEM) examination of the Burger’s vector of dislocations in tensile tested specimens revealed 〈1 0 0〉-type dislocations. TEM analysis suggested that a secondary slip system, {0 0 1}〈1 0 0〉, may be active. Banded features with a {0 2 1} orientation were observed in deformed YZn; these may be slip traces produced by the cross-slip of 〈1 0 0〉 dislocations. Acting together, {0 1 1}〈1 0 0〉 and {0 0 1}〈1 0 0〉 slip provide only three independent slip systems, and no extra independent systems are provided by the cross-slip. This finding is consistent with the low ductility of YZn.