Eventos Anais de eventos
COBEM 2019
25th International Congress of Mechanical Engineering
INFLUENCE OF DEEP CRYOGENIC TREATMENT oN THE CYCLIC BEHAVIOR OF A PSEUDOELASTIC NI57TI43 ALLOY
Submission Author:
Debora Bartasevicius , DF , Brazil
Co-Authors:
Debora Bartasevicius, Edson Paulo da Silva, Bernardo da Silva
Presenter: Debora Bartasevicius
doi://10.26678/ABCM.COBEM2019.COB2019-0953
Abstract
This work investigates the influence of Deep Cryogenic Treatment (DCT) on the cyclic behavior of a pseudoelastic Ni57Ti43 Shape Memory Alloy. The studied material is a Ni57Ti43 drawn wire of 3.81 mm diameter that presents an Af of 3.31 ºC, therefore a pseudoelastic behavior is expected at room temperature. The test specimens were machined accordingly to ASTM E-466-15 for force controlled fatigue testing in metallic materials and half were submitted to cryogenic immersion of 24 hours. Both treated and non treated specimens were submitted to a cyclic tension testing. To define the stress levels at the fatigue testing, tensile tests were taken adopting the methodology covered in the ASTM F-2516-06. The fatigue tests were conducted on a MTS 647 Hydraulic Wedge Grip. The initial, intermediate and final pseudoelastic curves of treated materials were compared to the ones obtained from the cycling of non treated materials. The results show an increase of the maximum strain, residual strain and hysteresis area for the specimens submitted to the DCT.
Keywords
NiTi, Deep Cryogenic Treatment, Fatigue Testing, microestructure, Pseudoelastic Effect
