A non-reflecting layer method for non-linear wave-type equations on unbounded domains with applications to shape memory alloy rods

Ferromagnetic shape memory alloy-based actuators offer distintive features that make them advantageous competitors to traditional electromechanical devices. The production of force and motion without contact is one of the most important features. However, the largely non-linear and hysteretic nature of the response of such materials makes them of little use apart from on-off or continuous actuation. In this work we present the results obtained in a laboratory prototype of linear position FSMA actuator, where the active element is a 12 mm long Ni-Mn-Ga single crystal. The crystal expands a maximum of 12 micrometers and in control experiments, is commanded to expand and contract alternatively to reach positions at 5 µm and 8 µm. It shows that the commanded position could be controlled within 20 nm.

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Development of a shape memory alloy multiple-point injector for chemotherapy

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1243/095441105x9354 ◽

2005 ◽

Vol 219 (3) ◽

pp. 213-217 ◽

Cited By ~ 4

Author(s):

W Xu ◽

T G Frank ◽

A Cuschieri

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Direct Injection ◽

Element Model ◽

Multiple Point ◽

Linear Elastic ◽

Outer Needle ◽

Non Linear ◽

Deformation Force ◽

Medical Needle

A medical needle is described that allows injection to take place at multiple sites through a single stab wound. This is achieved by extruding multiple, thin, and curved internal needles from a larger, straight, outer needle. The development and finite element modelling of the shape memory alloy (SMA) inner needles is presented in this paper. A non-linear elastic element model was used in this process to allow for the non-linear properties of the alloy and the large deformations that occur. The model provided maximum strain values and penetration forces for the inner needles. The deformation force on the tip of the needle was measured against displacement to confirm the predicted penetration force. Applications for the device include the treatment of liver cancer by direct injection of alcohol into the tumours.

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Non-linear transient dynamic analysis of sandwich plate with composite face-sheets embedded with shape memory alloy wires and flexible core- based on the mixed LW (layer-wise)/ESL (equivalent single layer) models

Composites Part B Engineering ◽

10.1016/j.compositesb.2015.10.008 ◽

2016 ◽

Vol 87 ◽

pp. 59-74 ◽

Cited By ~ 36

Author(s):

M. Botshekanan Dehkordi ◽

S.M.R. Khalili ◽

E. Carrera

Keyword(s):

Shape Memory Alloy ◽

Dynamic Analysis ◽

Shape Memory ◽

Sandwich Plate ◽

Single Layer ◽

Transient Dynamic Analysis ◽

Transient Dynamic ◽

Non Linear ◽

Composite Face ◽

Flexible Core

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Analytical study of thermal buckling and post-buckling behavior of composite beams reinforced with SMA by Reddy Bickford theory

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x211011668 ◽

2021 ◽

pp. 1045389X2110116

Author(s):

Mahshad Fani ◽

Fathollah Taheri-Behrooz

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Composite Structures ◽

Volume Fraction ◽

Thermal Buckling ◽

Constitutive Law ◽

Beam Deflection ◽

Buckling Behavior ◽

Non Linear ◽

Post Buckling

Shape memory alloys are used in composite structures due to their shape memory effect and phase transformation. The recovery force of the shape memory alloy improves the post-buckling behavior of the structure. In this study, the thermal buckling and post-buckling of Shape Memory Alloy (SMA) hybrid composite laminated beam subjected to uniform temperature distribution is investigated. To this purpose, considering Von-Karman non-linear strain terms for large deformation, the non-linear equations of SMA reinforced beam based on Reddy Bickford theory have been derived. Besides, the recovery stress of the restrained SMA wires during martensitic transformation was calculated based on the one-dimensional constitutive law of the Brinson’s model. A numerical solution using Galerkin’s method has been presented for solving the nonlinear partial differential equations to obtain the critical buckling temperature and transverse deformation of the beam in the post-buckling region in both symmetric and anti-symmetric layups. The effect of SMA volume fraction, pre-strain, the boundary condition of the beam, stacking sequence, and its geometric properties have been studied. The results show that even by adding a small amount of SMA to the composite, the critical buckling temperature increases significantly, and the beam deflection decreases. Besides, using this theory has an evident effect on the anti-symmetric layup, especially for the thick beams.

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