The strength anomaly in IVa-VIII B2 ordered intermetallics was characterized by using compression tests. It was shown that these compounds exhibited a typical positive temperature dependence of the yield stress at intermediate temperatures. The activated slip systems in these compounds were shown to be <001>{110}. Also, transmission electron microscopic and high-resolution electron microscopic observations indicated that the <001> dislocation was not clearly dissociated into super-partials, but possessed an asymmetrical non-compact core structure. It was proposed that the core configuration of the <001> dislocation became sessile under the influence of temperature and the applied stress. The observed strength anomaly at intermediate temperatures was related to the phase stability of the B2 structure.

T.Takasugi, S.Hanada, M.Yoshida, D.Shindo: Philosophical Magazine A, 1995, 71[2], 347-58