Abstract:
Based on the theory of diffuse martensitic transitions (DMT), the physical mechanism of the influence of dispersed precipitate nanoparticles on the appearance of such features of the deformation behavior of alloys with the shape memory effect (SME) as the stabilization of martensite at temperatures significantly higher than the $A_s$ and $A_f$ temperatures characteristic of an alloy in the absence of nanoparticles c-oherent with the matrix is analyzed. The reason for the stabilization of martensite is the internal elastic stress fields associated with the particles, which serve as sites for the heterogeneous nucleation of martensite. It has been shown theoretically that, with an increase in the volume concentration of nanoparticles, the recovery of shape memory deformation occupies an increasingly narrow temperature range and occurs at an ever higher temperature. After reaching a certain critical value of the particle concentration, the return of the deformation of SM loses its stability and becomes explosive.
Keywords:alloys with SME, dispersed nanoparticles, stabilization of martensite, stable and unstable (explosive) martensitic transition.
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