The Influence of Aging Treatments on a Ti-Ni 50.7 at. % Mechanical Spring Hugo De Souza Oliveira1; Henrique Alves Bandeira2; Aline Souza De Paula1; 1UNIVERSITY OF BRASILIA, Brasilia, Brazil; 2UNIVERSITY OF BRASILIA, Brasília, Brazil; PAPER: 363/Manufacturing/Regular (Oral) SCHEDULED: 14:50/Wed./Mar Azul (50/1st) ABSTRACT: Near equiatomic Ti-Ni shape memory alloys have been attracting much interest for practical applications in many research fields, such as medical, orthodontic, mechanical, and aerospace industries [1], [2]. <br />The remarkable ability in recovering large strains as well as generating high stresses has caused an increase in manufacturing devices made up of these materials[1], [3]-[5].<br />Many studies assert that shape memory characteristics of binary Ti-Ni alloys can be improved through specific thermomechanical treatments, such as annealing following cold working [6]-[8], thermal and/or stress cycling [9], and aging after solution treatment [6], [8], [10]. For Ni rich Ti-Ni alloys, aging treatment is the most effective method for improving the shape memory and mechanical characteristics of the alloys [6], [8], [10].<br />In literature, many studies correlate the effects of aging treatments on the transformation behavior of the Ti-Ni alloys [5], [6], [11]-[15], however few focus on how it can influence the stress-strain hysteresis in mechanical elements [3], such as mechanical springs. This study presents how aging treatments ranging from low to high temperatures (573K to 773K) [16] for different times can affect the cyclic hysteretic behavior of a Ti-Ni 50.7 at. % shape memory spring. The findings enable the choice of appropriate heat treatments where specific energy dissipation rates are required. References: [1] D. C. Lagoudas, Shape Memory Alloys: Modeling and Engineering Applications. Springer, 2008.<br />[2] J. Mohd Jani, M. Leary, A. Subic, and M. A. 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