Evolution of macroscopic elastic moduli of martensitic polycrystalline NiTi and NiTiCu shape memory alloys with pseudoplastic straining

Thomasová, Martina; Seiner, Hanuš; Sedlák, Petr; Frost, Miroslav; Ševčík, Martin; Szurman, Ivo; Kocich, Radim; Drahokoupil, Jan; Šittner, Petr; Landa, Michal

doi:10.1016/j.actamat.2016.10.024

Cited by 52 publications

(34 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It was observed that the elastic coefficients of martensite depend on stress in a fully reversible manner. After unloading, the oriented martensite retains its anisotropic elasticity, which is entirely in compliance with the results found by ex situ measurement presented by Thomasová et al [9].…”

Section: Resultssupporting

confidence: 92%

“…Laser-ultrasound measurements, such as the resonant ultrasound spectroscopy (RUS) comprise a great tool to study the highly anisotropic materials [7] and the temperature-dependent behavior of materials [8]. Recently, Thomasová et al [9] presented an ex situ study of the strain-dependence of elastic properties of martensitic structures in polycrystalline NiTi. It was shown in this work that the macroscopic moduli of polycrystalline SMAs can be strongly anisotropic under certain circumstances -in this particular case after stress-induced reorientation of martensitic structure by a uniaxial compression.…”

Section: Introductionmentioning

confidence: 99%

“…The elastic constants of a polycrystalline SMA depend on single-crystal elastic coefficients of the individual * corresponding author; e-mail: grabec@ujf.cas.cz phases present in the aggregate, the volume fractions of these phases, on the crystallographic texture of austenite, the martensitic microstructure, and the mutual morphology of austenite and martensite [9]. In this work, the development of elastic properties and overall anisotropy of a sample undergoing a compressional loading is studied.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

<em>In Situ</em> Characterization of the Elasticity and Stress-Induced Phase Transformation of NiTi Shape-Memory Alloy

et al. 2018

View full text Add to dashboard Cite

In the presented paper, a sample of polycrystalline shape-memory NiTi alloy is studied under compression up to 5% by the means of laser-excited and laser-detected ultrasound waves. The evolution of a propagation velocity of the surface acoustic wave is measured in situ during mechanical loading. An inverse method based on the Ritz-Rayleigh numerical approach is then used to obtain the development of elastic properties of the sample. This process enables an analysis of the evolution of stress-induced transformation from the austenitic to the martensitic phase with the possibility to describe several stages of such transformation, i.e., the transformation to full R-phase, its reorientation causing strong anisotropy of the polycrystalline sample, and consecutive gradual transition to martensite.

show abstract

Section: Resultssupporting

confidence: 92%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

<em>In Situ</em> Characterization of the Elasticity and Stress-Induced Phase Transformation of NiTi Shape-Memory Alloy

et al. 2018

View full text Add to dashboard Cite

show abstract

“…, 12 ) to ensure that the rate of transformation is larger than the rate of straining; and (ψ i − ψ 0 ) = 18 MPa ( Gall et al, 2001;. In contrast to polycrystalline aggregates, single crystal shape memory alloys exhibit elastic anisotropy in both martensite and austenite phases ( Thomasová et al, 2017 ). The elastic constants for the austenite and one of the martensitic variants are presented in Eq.…”

Section: Problem Formulation and Materials Propertiesmentioning

confidence: 99%

Microscale phase field modeling of the martensitic transformation during cyclic loading of NiTi single crystal

Esfahani

Ghamarian

Levitas

et al. 2018

International Journal of Solids and Structures

View full text Add to dashboard Cite

A microscale phase field model developed in Levitas et al. (2004) and Idesman et al. (2005) is slightly advanced for different and anisotropic elastic moduli of phases and is employed for the study of the stressinduced cubic-monoclinic phase transition in NiTi single crystal involving all 12 martensitic variants. The model is scale-independent, without the gradient term, and it is applicable for any scale greater than 100 nm. This model includes strain softening and the corresponding transformation strain localization, and it reproduces a discrete martensitic microstructure. The model only tracks finite-width interfaces between austenite and the mixture of martensitic variants, and does not consider the interfaces between martensitic variants. The model is implemented as a UMAT subroutine in a commercial finite element (FE) package, ABAQUS. Multiple problems for a uniaxial cyclic loading are solved to study the effect of mesh, strain rate, crystal orientation, different numbers of pre-existing nuclei, and the magnitude of the athermal threshold on the stress-strain responses as well as the microstructure evolution. The obtained results exhibit that the microstructure and global stress-strain responses are practically independent of mesh discretization and the applied strain rate for relatively small strain rates. While the presence of the initial nuclei in the sample decreases the nucleation stress, it slightly increases the total energy dissipation. The observed microstructure, the sudden drop in the stress-strain curve after initiation of the martensitic transformation, and the absence of a similar jump for the reverse phase transformation are in qualitative agreement with known experiments. Changing the crystallographic orientation of the sample varies the entire behavior, namely, the variants which are involved in the phase transformation, the morphology of the associated microstructure, the stress-strain curve, and the total dissipation. Athermal threshold, in addition to the expected increase in the magnitude of hysteresis, leads to some strain hardening for the direct phase transformation. a b s t r a c t A microscale phase field model developed in Levitas et al. (2004) and Idesman et al. ( 2005) is slightly advanced for different and anisotropic elastic moduli of phases and is employed for the study of the stressinduced cubic-monoclinic phase transition in NiTi single crystal involving all 12 martensitic variants. The model is scale-independent, without the gradient term, and it is applicable for any scale greater than 100 nm. This model includes strain softening and the corresponding transformation strain localization, and it reproduces a discrete martensitic microstructure. The model only tracks finite-width interfaces between austenite and the mixture of martensitic variants, and does not consider the interfaces between martensitic variants. The model is implemented as a UMAT subroutine in a commercial finite element (FE) package, ABAQUS. Multiple problems for a uniaxial cyclic loading are solved to st...

show abstract

“…Generally, Ti and its alloys are used for bone ixation, joint substitution, pacemakers, implants for dental, artiicial heart valves, components and stents in rapid blood centrifuges due to their chemical stability and particular high strength [24]. Central position has been made for a commercially pure Ti (cp-Ti, ASTM F67), Ti6Al4V alloy (ASTM F136) strengthened by alloys obtained by the modiication of them and Ti-based shape memory alloys (SMA) [25,26]. Cp-Ti is typically used in dental and spinal surgery, Ti6Al4V for the manufacturing of artiicial knee, hip and shoulder joints and for bone ixators, while SMAs are employed as orthodontic equipment and temporary spine and long bones ixations.…”

Section: Outlinementioning

confidence: 99%

Up-to-Date Knowledge and Outlooks for the Use of Metallic Biomaterials: Review Paper

Peter¹,

Matekovits²,

Rosso³

2018

Biomaterials in Regenerative Medicine

View full text Add to dashboard Cite

In all cases, when a material has to be used in medical applications, the knowledge of its physical, chemical and biological properties is of fundamental signiicance, since the direct contact between the biological system and the considered device could generate reactions whose long-term efects must be clearly quantiied. The class of materials that exhibits characteristics that allow their use for the considered applications are commonly called biomaterials. Patients sufering from diferent diseases generate a great demand for real therapies, where the use of biomaterials are mandatory. Commonly, metallic biomaterials are used because their structural functions; the high strength and resistance to fracture they can ofer, provide reliable performance primarily in the ields of orthopedics and dentistry.In metals, because of their particular structure, plastic deformation takes place easier, inducing good formability in manufacturing. The present paper is not encyclopaedic, but reports in the irst part some current literature data and perspectives about the possibility of use diferent class of metallic materials for medical applications, while the second part recalls some results of the current research in this ield carried out by the authors.

show abstract

Evolution of macroscopic elastic moduli of martensitic polycrystalline NiTi and NiTiCu shape memory alloys with pseudoplastic straining

Cited by 52 publications

References 47 publications

<em>In Situ</em> Characterization of the Elasticity and Stress-Induced Phase Transformation of NiTi Shape-Memory Alloy

<em>In Situ</em> Characterization of the Elasticity and Stress-Induced Phase Transformation of NiTi Shape-Memory Alloy

Microscale phase field modeling of the martensitic transformation during cyclic loading of NiTi single crystal

Up-to-Date Knowledge and Outlooks for the Use of Metallic Biomaterials: Review Paper

Contact Info

Product

Resources

About