Anomalous strengthening behavior of Co-Cr-Mo alloy single crystals for biomedical applications

This is the first repot on the deformation behavior of Co-Cr-Mo biomedical alloy single crystals predominantly having an fcc structure. In the single crystal, one of four epsilon-variants was selectively formed, and its geometry was found to drastically affect the mechanical properties. The yield stress in the 1111] orientation, in which the formation of epsilon-phase strain-induced martensite (SIM) crosses the grown-in epsilon-variant, was more than six times larger than that in the [149] orientation, where SIM was formed parallel to the grown-in s-variant. The intersection mechanism of the epsilon-variants is discussed via observations of the deformation microstructure. (C) 2016 Elsevier B.V. All rights reserved.