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E. Povoden-Karadeniz, D. Cirstea, E. Kozeschnik:
"Prediction of precipitate evolution and martensite transformation in Ti-Ni-Cu shape memory alloys by computational thermodynamics";
in: "IOP Conference Series: Materials Science and Engineering (ic-cmtp3: 3rd International Conference on Competitive Materials and Technology Processes, 2014, Miskolc)", Volume 123; IOP Publishing, UK, 2016, Paper ID 012038, 7 pages.

Ti-50Ni to Ti-55Ni (at.%) can be termed as the pioneer of shape memory alloys (SMA). Intermetallic precipitates play an important role for strengthening. Their influence on the start temperature of the martensitic transformation is a crucial property for the shape memory effect. Efforts for increasing the martensite start temperature include replacement of a part of Ni atoms by Cu. The influence of Cu-addition to Ti-Ni SMA on T0- temperatures and the character of the austenite-martensite transformation is evaluated using a new thermodynamic database for the Ti-Ni-system extended by Cu. Trends of precipitation of intermetallic phases are simulated by combining the assessed thermodynamics of the Ti-Ni-Cu system with assessed diffusion mobility data and kinetic models, as implemented in the solid-state transformation software MatCalc and are presented in the form of time-temperature-precipitation diagrams. Thermodynamic equilibrium considerations, complemented by predictive thermo-kinetic precipitation simulation, facilitates SMA alloy design and definition of optimized aging conditions.

http://dx.doi.org/10.1088/1757-899X/123/1/012038

http://publik.tuwien.ac.at/files/publik_255283.pdf