Investigation of physical metallurgy characteristics of two-way shape memory effect in TiNi alloy FILIP, P., MAZANEC, K. vol. 39 (2001), no. 1, pp. 31 - 39
Abstract The two-way shape memory effect (TWSME) represents a behaviour in which a reversible temperature change of a "memory alloy" is accompanied with spontaneous reversible macroscopic deformations. It was generally accepted that internal defects, which are introduced during the so called training procedure, are responsible for this phenomenon. The formation of ghost martensite may contribute to the enhanced reversibility of binary TiNi system without R-phase formation. The aim of this study is to investigate TiNi materials in which R-phase formation occurs. The trained specimens contain dislocation array, stabilised martensite and ghost martensite. It is expected, owing to the specific crystallographic relation, that ghost martensite formation can facilitate both the R-phase formation as well as B 19' martensite formation and in this way support the reversible memory of TiNi alloys. Key words shape memory alloy, two-way shape memory effect, ghost martensite, R-phase, B 19' martensite, training procedure, hard, soft training Full text (3942 KB)
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