Thermal Treatment Related Structure and Property Changes in a TiNi Alloy Presenting Shape Memory Effect

Abstract:

Changes in the structure and properties of a TiNi alloy, which possesses shape memory effect by means of reversible martensitic transformation (RMT), after annealing at different temperatures in the interval of 300 to 550oC, were investigated. These changes were characterized by chemical analysis, X-ray diffraction, electrical resistivity, microhardness and differential scanning calorimetry. The results showed that the as-fabricated TiNi alloy presented a multiphase structure. An additional high temperature phase was revealed upon 550oC annealing. The alloy displayed sensible changes in its electrical resistivity that were attributed to the influence of the several existing phases. A tendency for the increase in the RMT critical temperatures was also observed with increasing annealing temperature.

• Periodical: Materials Science Forum (Volumes 775-776)
• Pages: 733-737
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.775-776.733
• Online since: January 2014
• Authors: Everton Maick Rangel Pessanha, Lioudmila Aleksandrovna Matlakhova, Herval Ramos Paes, Ruben Jesus Sanchez Rodriguez, Veronica Scarpini Candido, Sergio Neves Monteiro
• Keywords: Property, Reversible Martensitic Transformation, Structure, Thermal Treatment, TiNi Alloy

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