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Quenched alloys from the Ti-Nb system are of considerable scientific and applied interest due to properties such as superconductivity, shape memory effect and high damping capacity. In this work, Ti-Nb quenched alloys with 2 wt.% Al and Nb content varying from 15 to 40% were investigated with respect to effects on phase transformations, internal friction and elastic modulus caused by the temperature up to 800°C. The results showed that the internal friction presented peaks and the elastic modulus displayed minimum values with the temperature. These results were associated with phase transformations occurring with increasing temperature.

In the present work a monocrystalline Cu-13.5Al-4Ni (wt.%) alloy with shape memory effect (SME) submitted to thermal cycling inside the critical range was investigated in terms of number of cycles and resulting structural changes. Attention was paid to the structural changes associated with reversible β1↔γ’1 martensite transformation. The monocrystalline Cu-Al-Ni alloy was produced in Russia, according to a specific technology. The structural characteristic of the alloys was studied through optical microscopy and X-ray diffraction methods using Cu-Kα radiation. Differential scanning calorimetry permitted the determination of the temperature range as well as a thermal effect due to the β1↔γ’1 martensitic reversible transformations, before and after 100, 200 and 300 thermal cycles.