Numerical Simulation of the Shape Memory Alloy Pipe Joint

Shape memory alloys have been actively studied in various fields in an attempt to utilize their high energy density. In particular, shape memory alloy wire-embedded composites can be used as load-bearing smart actuators without any additional manipulation, in which they act like a hinge joint. A shape memory alloy wire-embedded composite is able to generate various deformation behaviors via the combination of its shape memory alloy and matrix materials. Accordingly, a study of the various design parameters of shape memory alloy wire-embedded composites is required to facilitate the practical application of smart structures. In this research, a numerical simulation of a shape memory alloy wire-embedded composite is used to investigate the deformation behavior of a composite panel as a function of the composite width per shape memory alloy wire, composite thickness, and the eccentricity of the shape memory alloy wire. A curved morphing composite structure is fabricated to confirm the results of the numerical simulation. The deformation of the shape memory alloy wire-embedded composite panel is determined by measuring its radius of curvature. The simulated deformation behaviors are verified with the experimental results. In addition, an analysis of the deformation and internal stress of the composites is carried out. It can be used to obtain guidelines for the mechanical design of shape memory alloy wire-embedded composite panels.

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Experimental Analysis and Numerical Simulation of Tensile Behaviour of TiNi Shape Memory Alloy Fibres Reinforced Epoxy Matrix Composite at High Temperatures

10.1063/1.3589640 ◽

2011 ◽

Author(s):

M. L. Sahli ◽

B. Necib

Keyword(s):

Numerical Simulation ◽

Shape Memory Alloy ◽

Shape Memory ◽

High Temperatures ◽

Matrix Composite ◽

Experimental Analysis ◽

Epoxy Matrix ◽

Tensile Behaviour ◽

Epoxy Matrix Composite

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Finite Element Simulation of NiTiNb Shape Memory Alloy Pipe-Joint Subjected to Coupled Transformation and Plastic Deformation

Advances in Materials Science and Engineering ◽

10.1155/2020/6895850 ◽

2020 ◽

Vol 2020 ◽

pp. 1-14

Author(s):

Xiang Chen ◽

Bin Chen ◽

Xianghe Peng ◽

Xiaoqing Jin ◽

Ying Ma ◽

...

Keyword(s):

Plastic Deformation ◽

Phase Transformation ◽

Shape Memory Alloy ◽

Shape Memory ◽

High Performance ◽

Coupling Effect ◽

Longitudinal Direction ◽

Design Parameters ◽

Pull Out ◽

Pipe Joint

The assembling process of Ni47Ti44Nb9 alloy pipe joints considering the phase transformation and plasticity was numerically simulated for the first time with a developed constitutive model. The simulated process was based on the experimental material parameters, which were determined with the experimental tensile results of Ni47Ti44Nb9 shape memory alloy (SMA) and steel bars. The results showed that, after assembly, the Mises stress distributed uniformly along the longitudinal direction of the NiTiNb joint, but nonuniformly along the radial direction. The maximum σeq does not appear at the inner wall of the joints due to the coupling effect of the plastic deformation and the recoverable transformation. The contact pressure distributed uniformly along the circumferential direction, but nonuniformly along the longitudinal direction. The sizes of the SMA joint and the pipe should be properly matched to ensure contact during the stage of the rapid reverse phase transformation to obtain stable connection performance. The pull-out force was also computed, and the results were in good agreement with the experimental results. The results obtained can provide available information for the optimization of the design parameters of the high-performance SMA pipe-joint, such as inner diameter and assembly clearance.

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A Study on Tensile Deformation Behavior in Fe-Based Shape Memory Alloy by Rate Sensitive Transformation Kinetics Model

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.725.77 ◽

2016 ◽

Vol 725 ◽

pp. 77-81

Author(s):

Anthony Budiaman ◽

Kazuki Fujita ◽

Takeshi Iwamoto

Keyword(s):

Numerical Simulation ◽

Shape Memory Alloy ◽

Shape Memory ◽

Deformation Behavior ◽

Tensile Deformation ◽

Rate Sensitivity ◽

Kinetics Model ◽

Strain Rates ◽

Transformation Kinetics ◽

Tensile Deformation Behavior

Fe-based shape memory alloy (Fe-SMA) shows a shape memory effect (SME) governed by forward and reverse stress-induced martensitic transformation (SIMT). Fe-SMA has been applied to joints and dampers utilized at various strain rates. To utilize Fe-SMA better, it is necessary to understand the mechanical properties in a wide range of strain rate. In previous study, the results of a tensile test at various strain rates show a rate-sensitivity, however, the mechanism of rate-sensitive tensile deformation behavior is still unclear. Thus, a numerical simulation using a transformation kinetics model is needed to clarify the mechanism. Some transformation kinetics models have been proposed, however, the rate sensitivity cannot be included. In this study, the rate sensitivity of volume fraction martensite is considered into the transformation kinetics model as an improvement of the past-proposed model. The numerical simulation of the uniaxial tensile test at various strain rates is performed to reproduce transformation behavior of the martensite phase. Then, the model is validated by comparing to the experimental results. Afterwards, the mechanism of rate-sensitive tensile deformation behavior of Fe-SMA is discussed.

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