Numerical simulations of temperature and stress field of Fe-Mn-Si-Cr-Ni shape memory alloy coating synthesized by laser cladding

In this paper a phase transformation equation is supposed to describe the phase transformation behaviors of the shape memory alloy (SMA) under complex stress state. The stress field near crack-tip of mode I in SMA at various temperatures is investigated based on the supposed phase transformation equation and linear elastic fracture mechanics. Results show both the martensite region and the mixed region of martensite and austenite near the crack-tip become larger with the decrease of temperature. The fracture mechanics behaviors of SMA are much influenced by the temperature.

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QUASIPASSIVITY-BASED ROBUST NONLINEAR FLAP POSITIONING CONTROL USING SHAPE MEMORY ALLOY MICRO-ACTUATORS

Transactions of the Canadian Society for Mechanical Engineering ◽

10.1139/tcsme-2005-0010 ◽

2005 ◽

Vol 29 (2) ◽

pp. 143-161

Author(s):

Nicolas Léchevin ◽

Camille Alain Rabbath ◽

Frank Wong ◽

O. Boissonneault

Keyword(s):

Shape Memory Alloy ◽

Nonlinear Control ◽

Numerical Simulations ◽

Shape Memory ◽

Position Control ◽

Tracking Error ◽

Constitutive Law ◽

Control Law ◽

Ultimate Boundedness ◽

Feedback Connection

This paper proposes a quasipassivity-based robust nonlinear control law ensuring position control of a rotary flap by means of an antagonist-type shape memory alloy microactuator. The control system employs variable-structure control to obtain robust performance, phase-lead compensation to quasipassivate the shape memory alloy dynamics and quasipassivity-based analysis to warrant robust ultimate boundedness of system trajectories. The feedback connection of the two paths leads to ultimate boundedness of tracking error trajectories of the plant despite uncertainties in the dynamic loads affecting the leading edge flap and in the friction found in the actuator. Since accurate numerical simulations and development of new concepts of microactuators based on shape memory alloys require a tractable, constitutive law accurately describing the relationship between force, displacement and temperature in the material, the paper also presents a hybrid micro-macro-mechanical shape memory alloy constitutive model. This model is based on a combination of structural modeling on a microscopic scale and transformation kinetics modeling on a macroscopic scale. The proposed control law and hybrid micro-macro-mechanical model are placed in closed-loop by means of numerical simulations that demonstrate the validity of the nonlinear control scheme.

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Study on Crack Tip Field of Shape Memory Alloy Board under Torsion Load

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.663.397 ◽

2013 ◽

Vol 663 ◽

pp. 397-402

Author(s):

Bo Zhou ◽

Tai Yue Yin ◽

Shi Feng Xue

Keyword(s):

Phase Transition ◽

Field Equation ◽

Shape Memory Alloy ◽

Stress Field ◽

Shape Memory ◽

Crack Tip ◽

Martensitic Phase ◽

Mechanical Behaviors ◽

Crack Tip Field ◽

Martensitic Phase Transition

This paper focuses on the thermo-mechanical behaviors of the shape memory alloy board with a crack and under the torsion load. A stress field equation from mechanics of elasticity is used to describe the stress distribution around the crack tip in the shape memory alloy board. A martensitic phase transition equation is supposed to predict the martensitic phase transition behaviors of the field near the crack tip in the shape memory alloy board. The martensitic phase transition zones near the crack tip in the shape memory alloy board under the torsion load are numerically described based on the stress field equation and martensitic phase transition equation at various temperatures. Results show that the stress field equation and martensitic phase transition equation can predict the thermo-mechanical behaviors of the shape memory alloy board with a crack and under the torsion load effectively.

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Overview and Future Advanced Engineering Applications for Morphing Surfaces by Shape Memory Alloy Materials

Materials ◽

10.3390/ma12050708 ◽

2019 ◽

Vol 12 (5) ◽

pp. 708 ◽

Cited By ~ 14

Author(s):

Andrea Sellitto ◽

Aniello Riccio

Keyword(s):

Shape Memory Alloy ◽

Shape Memory Alloys ◽

Mechanical Behavior ◽

Numerical Simulations ◽

Shape Memory ◽

Smart Structures ◽

Aerodynamic Performance ◽

Research Field ◽

Simplified Model ◽

Land Vehicles

The development of structures able to autonomously change their characteristics in response to an external simulation is considered a promising research field. Indeed, these structures, called smart structures, can be adopted to improve the aerodynamic performance of air and land vehicles. In this work, an overview and future applications of Shape Memory Alloys (SMA)-based smart structures are presented. The use of SMA materials seems to be very promising in several engineering sectors. Advanced SMA-based devices, designed to improve the aerodynamic performance of vehicles by modifying the shape of the spoiler and the rear upper panel, are briefly introduced and discussed in this paper. Indeed, a simplified model simulating the SMA mechanical behavior has been considered to demonstrate the feasibility of the introduced smart structures for adaptive aerodynamic applications. Numerical simulations of the investigated structures are provided as a justification of the proposed designs.

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Residual stress simulation and measurement of Fe-Mn-Si shape memory alloy coating

Infrared and Laser Engineering ◽

10.3788/irla201746.1017009 ◽

2017 ◽

Vol 46 (10) ◽

pp. 1017009

Author(s):

鞠恒 Ju Heng ◽

林成新 Lin Chengxin ◽

张佳琪 Zhang Jiaqi ◽

刘志杰 Liu Zhijie

Keyword(s):

Residual Stress ◽

Shape Memory Alloy ◽

Shape Memory ◽

Alloy Coating ◽

Stress Simulation

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Numerical Simulations of NiTi Shape Memory Alloy Wire Behaviors in Tension, Compression, and Torsion

Acta Physica Polonica A ◽

10.12693/aphyspola.134.842 ◽

2018 ◽

Vol 134 (3) ◽

pp. 842-846 ◽

Cited By ~ 2

Author(s):

P. Sedlák ◽

M. Frost

Keyword(s):

Shape Memory Alloy ◽

Numerical Simulations ◽

Shape Memory ◽

Niti Shape Memory Alloy ◽

Shape Memory Alloy Wire ◽

Alloy Wire

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Response of Optical Fiber Bragg Sensors With a Thin Film Shape Memory Alloy Coating

Smart Materials, Adaptive Structures and Intelligent Systems, Volume 1 ◽

10.1115/smasis2008-455 ◽

2008 ◽

Cited By ~ 1

Author(s):

K. P. Mohanchadra ◽

Michael C. Emmons ◽

Sunny Karnani ◽

Gregory P. Carman ◽

W. Lance Richards

Keyword(s):

Thin Film ◽

Shape Memory Alloy ◽

Optical Fiber ◽

Shape Memory ◽

Alloy Coating ◽

Niti Shape Memory Alloy ◽

Alloy Thin Film ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Transformation Temperatures

This paper describes the sputter deposition and characterization of nickel titanium (NiTi) shape memory alloy thin film onto the surface of an optical fiber Bragg sensor. The NiTi coating uniformity, crystallinity and transformation temperatures are measured using scanning electron microsocopy, x-ray diffraction and differential scanning calorimetry respectively. The strain in the optical fiber is measured using centroid calculation of wavelength shifts. Results show distinct and abrupt changes in the optical fiber signal with the four related transformation temperatures represented by the austenite-martensite forward and reverse phase transformations. These tests demonstrate a coupling present between optical energy and thermal energy, i.e. a modified multiferroic material.

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