CuZr Based Shape Memory Alloys: Effect of Cr and Co on the Martensitic Transformation

In the present work an investigation on CuZr based shape memory alloys was proposed. In particular, this study has been addressed the effect of the addition of Cr and Co on the martensitic transformation behaviour. The characterization was performed using DSC in terms of evolution of characteristic temperatures. The analysis of the proposed alloys was completed with the evaluation of the microhardness and the microstructure, observed by means of a scanning electron. Moreover, X-rays diffraction analysis was also carried out to check the crystal structures in the different alloys. It was shown how the addition of Co can improve thermal stability and the thermal hysteresis of the martensitic transformation by the first thermal cycles, even if the characteristic temperatures were significantly decreased.

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