Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
Finite strain modeling of coupled thermo-mechanical behavior of polycrystalline ni-ti shape memory alloys
Download
index.pdf
Date
2017
Author
Rezazadeh, Vahid
Metadata
Show full item record
Item Usage Stats
188
views
232
downloads
Cite This
Shape memory alloys (SMAs) hold a significant importance in different areas such as aeronautics,adaptive structures,oil/gas down-hole, and high-temperature applications of automobile industry. Nowadays,researchers have already become well-aware of these applications and attempted to discover all the primary features of this specific smart material. Meanwhile, there is a growing effort to produce mathematical models in order to imitate the related behavior in a precise manner. Due to the crucial need to have a fine computational model, we established a constitutive theory based on the finite strain framework of continuum mechanics. The presented thermo-mechanically coupled model can perfectly reproduce all behavior of Ni-Ti SMAs including martensitic phase transformation, pseudoelasticity, and one-way shape memory effect. Our constitutive model is also able to investigate the strain-rate and temperature dependency of the loading conditions. This work aims at utilising finite strain plasticity set- ting with purely thermodynamically consistent constitutive equations. In this framework, a user material subroutine (UMAT) is written and implemented into ABAQUS/Implicit (2016) finite element program. Verification of the model is carried out by the calibrated experimental findings which exist in the literature. Numerical simulations of developed constitutive model successfully denote the ability of our phenomenological model in capturing different memory effects of Ni-Ti SMAs under stress-strain-temperature cycling.
Subject Keywords
Plasticity.
,
Shape memory alloys.
,
Nickel-titanium alloys.
,
Finite element method.
,
Martensitic transformations.
URI
http://etd.lib.metu.edu.tr/upload/12621559/index.pdf
https://hdl.handle.net/11511/26627
Collections
Graduate School of Natural and Applied Sciences, Thesis
Suggestions
OpenMETU
Core
Precise position control using shape memory alloy wires
Donmez, Burcu; Ozkan, Bulent; Kadıoğlu, Fevzi Suat (2010-01-01)
Shape memory alloys (SMAs) are active metallic "smart" materials used as actuators and sensors in high technology smart systems [1]. The term shape memory refers to ability of certain materials to "remember" a shape, even after rather severe deformations: once deformed at low temperatures, these materials will stay deformed until heated, whereupon they will return to their original, pre-deformed "learned" shape [2]. This property can be used to generate motion and/or force in electromechanical devices and m...
FINITE ELEMENT ANALYSIS OF NANOINDENTATION ON NANOLAMINATED MATERIALS
Özerinç, Sezer (2018-12-01)
Nanoindentation is a widely used tool for probing the mechanical properties of materials at the nanoscale. The analysis of the load-displacement curve obtained from nanoindentation provides the hardness and elastic modulus of the material. While hardness is a useful parameter for comparing different alloys and understanding tribological behavior, yield strength is a more useful parameter for alloy design and application in general. The yield strength of a nanoindentation-tested material can be estimated by ...
Annealing of cold rolled and swaged AZ31 magnesium alloy /
Tunca, Bensu; Bor, Şakir; Department of Metallurgical and Materials Engineering (2014)
Magnesium alloys are extensively used in electronics, automotive and aerospace industries due to their low densities and high specific strengths; however limited deformability of magnesium alloys at room temperature restricts the applications. Grain refinement as a result of recrystallization can be used to enhance the deformability of these alloys. In this dissertation, recrystallization behavior of cold rolled and swaged AZ31 alloy is investigated at different temperatures in the range of 100°C - 300°C. E...
Design and analysis of a linear shape memory alloy actuator
Söylemez, Burcu; Kadıoğlu, Fevzi Suat; Department of Mechanical Engineering (2009)
Shape memory alloys are new, functional materials used in actuator applications with their high power to weight ratio. The high strength or displacement usage of shape memory alloys makes them suitable for direct drive applications, which eliminate use of power transmission elements. The aim of this research is to develop the methodology and the necessary tools to design and produce linear shape memory alloy actuators to be used in missile systems, space applications, and test equipments. In this study, the...
Synthesis and structural characterization of multifunctional Ti alloy: gum metal
Elçin, Orkun; Akdeniz, M. Vedat.; Department of Metallurgical and Materials Engineering (2020)
Gum metal (Ti-23Nb-0.7Ta-2Zr-1.2O at%), a newly discovered titanium alloy, is considered as a suitable unique alloy for structural applications in aerospace, sports equipment, industrial, and especially in biomedical areas because of their outstanding properties such as high yield strength (up to 2000 MPa) with low elastic modulus (50 GPa), and biocompatibility. Furthermore, in the heavily deformed state, it still possesses an ultra-low elastic modulus, ultra-high-strength, large elasticity (up to 2.5%), El...
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
V. Rezazadeh, “Finite strain modeling of coupled thermo-mechanical behavior of polycrystalline ni-ti shape memory alloys,” M.S. - Master of Science, Middle East Technical University, 2017.