Shape memory effect in Ti50Ni50-xZrx alloys

The phase composition, martensitic transformation (MT) completeness, mechan ical and, in particular, shape memory behavior have been investigated in th e Ti50Ni50-xZrx alloys under the B2 double left right arrow B19 ' martensit ic transformation. All investigated alloys are found to exhibit the shape m emory effect (SME); however, its characteristics essentially depend on the Zr-content. The Ni substitution by Zr is shown to result in the appearance of noticeable quantity of secondary phase, decreasing the MT completeness, the fragility of alloys, the low ultimate torsion stress of the B2 parent p hase and the SME temperature hysteresis width growth. All these lead to the SME degeneration in the Ti50Ni50-xZrx alloys. (C) 2001 Elsevier Science B. V. All rights reserved.