de Azevedo Melo, T. A.; Gomes, R. Medeiros; da Silva Júnior, M. Q.; de Lima, S. J. Guedes; Brito, I. C. Andrade
January 2010
Acta Microscopica;2010, Vol. 19 Issue 1, p114
Academic Journal
Polycrystalline specimens of Cu-Al-Be shape memory alloys were homogenized at 1123K during 12h and water-quenched at room temperature. The phase transformation temperatures were determined via optical microscopy technique, using a cooling/heating device attached to the microscope stage. Comparisons have been made with data obtained via differential scanning calorimetry. The data show that the former technique can be successfully applied to the determination of typical transition temperatures occurring in shape memory alloys. As far as sample related problems are concerned, the former technique can also represent an advantageous alternative over the latter given the fact that the analyses can be performed in more representative area. The Mf and As temperatures precise detection depend on the chosen resolution of the optical microscope.


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