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The properties of the Ti50Pd40Ni10 (at %) alloy showing the high-temperature shape memory effect are studied in detail using samples made of a 5.86 mm bar under various conditions of annealing and induced deformation. The data on the phase transformation temperatures and the mechanical and thermomechanical characteristics of the alloy are obtained. The range of phase transformations occurs in the range from Mf = 360°C to Af = 439°C. These are acceptable values for creating the required safety device. The maximum values of the shape memory effect and the degree of shape recovery are 2.4 and 43%, respectively. This is not sufficient to create a functional security device. Thus, the selection of annealing modes and conditions for inducing deformation are not a successful way to substantially increase the thermomechanical characteristics of the alloy. Higher values of thermomechanical characteristics have previously been obtained using samples cut from a strip with a thickness of 2.04 mm. Therefore, operating elements of safety devices designed for nuclear power facilities will be further manufactured from the strip. [ABSTRACT FROM AUTHOR]

Abstract—Complex studies of the properties of the Ti50Pd40Ni10 alloy (at %) with a high-temperature shape memory effect have been performed using specimens prepared from a 5.86-mm bar in the initial annealed state. Information on the temperatures of phase transformations and mechanical and thermomechanical characteristics of the alloy have been obtained. The maximum values of the shape-memory effect and of the degree of shape recovery were 1.5 and 21%, respectively. This is insufficient to create workable safety devices at this stage. The thermomechanical characteristics determined in this study are comparable with the data we obtained earlier on samples cut out from a 2.04-mm-thick strip. In spite of the rather low values of the thermomechanical characteristics obtained at the first stage of research, this alloy is a promising material, and if obtaining optimum values of working characteristics by varying manufacturing conditions and regimes of heat treatment and deformation, it can be used to create working elements of various safety devices for objects of nuclear power engineering. [ABSTRACT FROM AUTHOR]

This work investigates the effect of the rate, temperature, and magnitude of the strain induced preliminarily to heating for developing shape memory effect on the phase composition, martensite transformation, phase transition temperature, lattice parameters, substructure parameters, and thermomechanic characteristics of the shape memory (SM) 45Ti–45Ni–10Nb (at %) alloy in the press-formed state. The relation between structural and thermomechanical parameters of the alloy is identified. The conditions of prestraining the SM alloy for achieving the best thermomechanic characteristics are determined. The results of this study have been used to develop a fire-protection device for nuclear power facilities. [ABSTRACT FROM AUTHOR]

Combined studies of the properties of the 50Ti-40Pd-10Ni alloy with a high-temperature shape memory effect have been carried out. The elemental and phase compositions and its mechanical and thermomechanical characteristics have been determined. Samples cut from the strip with a thickness of 2.04 mm have been studied. The phase transformations are in the range of Mf = 371.3°С to Af = 436.9°С. These are acceptable values. The maximum values of the shape memory effect εSME and of the degree of shape recovery ηSME are 3.9 and 49%, respectively. These values are insufficient to create workable safety devices. These characteristics can be improved via optimal changes in the elemental composition of the shape memory alloy and by an adequate choice of the regimes of heat treatment and of the regimes of providing strain in the investigated objects. The results of these studies are necessary in order to develop different devices used in nuclear power plants. [ABSTRACT FROM AUTHOR]