Microstructural dependence on middle eigenvalue in Ti-Ni-Au

Abstract The microstructure of various compounds of the Ti–Ni–Au alloy system is investigated by transmission electron microscopy in relation with changing lattice parameters improving the compatibility conditions between austenite and martensite expressed by the λ 2  = 1 equation based on the Geometrically NonLinear Theory of Martensite (GNLTM). Although local differences in microstructure are observed, when increasing the gold content compound twins are replaced by Type I twins, while twinned lamellar structures are replaced by untwinned plates and self-accommodating structures when λ 2  = 1 is approached, all confirming the predictions of the GNLTM.

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