Experimental study on the low-velocity impact failure mechanism of foam core sandwich panels with shape memory alloy hybrid face-sheets

Abstract Superelastic shape memory alloy (SMA) as an advanced smart material has been used to improve the impact performance of fiber-reinforced composites in recent decades. Due to the low impact toughness of the thin composite face-sheet and the poor strength of the foam core, sandwich panels are sensitive to the transverse loading. SMA fibers were embedded into the composite laminated to improve the impact resistance of the traditional foam core sandwich panel in this work. Five new types of SMA hybrid panels were prepared, and the testing panels with penetration failure were observed at the impact energy of 50 J. The impact mechanical responses and the damage morphology were analyzed, and the impact failure mechanism was also revealed. Results show that all sandwich panels were failed, the fiber breakage occurred at the impact region in the traditional panels, while part plies of the rear face-sheets split-off in the SMA hybrid panels. The impact performance of the SMA hybrid panels is improved when compared with the traditional panel, the reduction of the delamination area by 48.15% and the increase of the load-bearing threshold by 32.75% are acquired for the hybrid sandwich panel with two layers of SMA fibers in the rear face-sheet.

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The low-velocity impact and compression after impact (CAI) behavior of foam core sandwich panels with shape memory alloy hybrid face-sheets

Science and Engineering of Composite Materials ◽

10.1515/secm-2019-0034 ◽

2019 ◽

Vol 26 (1) ◽

pp. 517-530 ◽

Cited By ~ 2

Author(s):

Ye Wu ◽

Yun Wan

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Sandwich Panels ◽

Image Correlation ◽

Low Velocity Impact ◽

Foam Core ◽

Low Velocity ◽

Velocity Impact ◽

Compression After Impact ◽

The Impact

AbstractDue to the properties of shape memory effect and super-elasticity, shape memory alloy (SMA) is added into glass fiber reinforced polymer (GFRP) face-sheets of foam core sandwich panels to improve the impact resistence performance by many researchers. This paper tries to discuss the failure mechanism of sandwich panels with GF/ epoxy face-sheets embedded with SMA wires and conventional 304 SS wire nets under low-velocity impact and compression after impact (CAI) tests. The histories of contact force, absorbed energy and deflection during the impact process are obtained by experiment. Besides, the failure modes of sandwich panels with different ply modes are compared by visual inspection and scanning electron microscopy (SEM). CAI tests are conducted with the help of digital image correlation (DIC) technology. Based on the results, the sandwich panels embedded with SMA wires can absorb more impact energy, and show relatively excellent CAI performance. This is because the SMA wires can absorb and transmit the energy to the outer region of GFRP face-sheet due to the super-elasticity-behavior. The failure process and mechanism of the CAI test is also discussed.

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The Influence of Shape Memory Alloy Volume Fraction on the Impact Behavior of Polymer Composites

Polymers ◽

10.3390/polym10111280 ◽

2018 ◽

Vol 10 (11) ◽

pp. 1280 ◽

Cited By ~ 2

Author(s):

Min Sun ◽

Xiaokun Sun ◽

Zhenqing Wang ◽

Mengzhou Chang ◽

Hao Li

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Polymer Composites ◽

Volume Fraction ◽

Low Velocity Impact ◽

Impact Behavior ◽

Low Velocity ◽

Velocity Impact ◽

Impact Performance ◽

The Impact

The low-velocity impact behavior of Shape Memory Alloy (SMA) reinforced resin matrix polymers is investigated and the influence of the SMA volume fraction on the impact performance of polymer composites is considered for the first time, which are the highlights in this paper. Firstly, 12 kinds of polymer composite specimens with different SMA volume fractions are fabricated in terms of the SMA layup spacing, SMA diameter, and the interaction between the two. Secondly, a low-velocity impact test is carried out in order to study the impact performances of the above polymer composites. Finally, the damage morphology of the specimen after impact is observed by the visualization method and the low-velocity impact performance of the 12 kinds of polymer composites is analyzed on the basis of the force and energy history curve.

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Mechanical Behaviour of Pin-Reinforced Foam Core Sandwich Panels Subjected to Low Impact Loading

Polymers ◽

10.3390/polym13213627 ◽

2021 ◽

Vol 13 (21) ◽

pp. 3627

Author(s):

Ali Farokhi Farokhi Nejad ◽

Seyed Saeid Rahimian Rahimian Koloor ◽

Syed Mohd Saiful Azwan Syed Hamzah ◽

Mohd Yazid Yahya

Keyword(s):

Mechanical Behaviour ◽

Impact Loading ◽

Sandwich Panel ◽

Experimental Testing ◽

Peak Load ◽

Sandwich Panels ◽

Sheet Thickness ◽

Element Model ◽

Foam Core ◽

The Impact

As a light structure, composite sandwich panels are distinguished by their significant bending stiffness that is rapidly used in the manufacture of aircraft bodies. This study focuses on the mechanical behaviour of through-thickness polymer, pin-reinforced foam core sandwich panels subjected to indentation and low impact loading. Experimental and computational approaches are used to study the global and internal behaviour of the sandwich panel. The samples for experimental testing were made from glass/polyester laminates as the face sheets and polyurethane foam as the foam core. To further reinforce the samples against bending, different sizes of polymeric pins were implemented on the sandwich panels. The sandwich panel was fabricated using the vacuum infusion process. Using the experimental data, a finite element model of the sample was generated in LS-DYNA software, and the effect of pin size and loading rate were examined. Results of the simulation were validated through a proper prediction compared to the test data. The results of the study show that using polymeric pins, the flexural strength of the panel significantly increased under impact loading. In addition, the impact resistance of the pin-reinforced foam core panel increased up to 20%. Moreover, the size of pins has a significant influence on the flexural behaviour while the sample was under a moderate strain rate. To design an optimum pin-reinforced sandwich panel a “design of experiment model” was generated to predict energy absorption and the maximum peak load of proposed sandwich panels. The best design of the panel is recommended with 1.8 mm face sheet thickness and 5 mm pins diameter.

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A numerical study of the impact perforation of sandwich panels with graded hollow sphere cores

Advances in Mechanical Engineering ◽

10.1177/16878140211009415 ◽

2021 ◽

Vol 13 (4) ◽

pp. 168781402110094

Author(s):

Ibrahim Elnasri ◽

Han Zhao

Keyword(s):

Boundary Conditions ◽

Hollow Sphere ◽

Sandwich Panel ◽

Numerical Study ◽

Sandwich Panels ◽

Hopkinson Bar ◽

Core Density ◽

The Core ◽

The Impact ◽

Force Displacement

In this study, we numerically investigate the impact perforation of sandwich panels made of 0.8 mm 2024-T3 aluminum alloy skin sheets and graded polymeric hollow sphere cores with four different gradient profiles. A suitable numerical model was conducted using the LS-DYNA code, calibrated with an inverse perforation test, instrumented with a Hopkinson bar, and validated using experimental data from the literature. Moreover, the effects of quasi-static loading, landing rates, and boundary conditions on the perforation resistance of the studied graded core sandwich panels were discussed. The simulation results showed that the piercing force–displacement response of the graded core sandwich panels is affected by the core density gradient profiles. Besides, the energy absorption capability can be effectively enhanced by modifying the arrangement of the core layers with unclumping boundary conditions in the graded core sandwich panel, which is rather too hard to achieve with clumping boundary conditions.

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Design and Optimization of a Shape Memory Alloy-Based Self-Folding Sheet

Journal of Mechanical Design ◽

10.1115/1.4025382 ◽

2013 ◽

Vol 135 (11) ◽

Cited By ~ 39

Author(s):

Edwin Peraza-Hernandez ◽

Darren Hartl ◽

Edgar Galvan ◽

Richard Malak

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Three Dimensional ◽

Building Blocks ◽

Passive Layer ◽

Von Mises Stress ◽

Maximum Temperature ◽

Radius Of Curvature ◽

Folding Angle ◽

The Impact

Origami engineering—the practice of creating useful three-dimensional structures through folding and fold-like operations on two-dimensional building-blocks—has the potential to impact several areas of design and manufacturing. In this article, we study a new concept for a self-folding system. It consists of an active, self-morphing laminate that includes two meshes of thermally-actuated shape memory alloy (SMA) wire separated by a compliant passive layer. The goal of this article is to analyze the folding behavior and examine key engineering tradeoffs associated with the proposed system. We consider the impact of several design variables including mesh wire thickness, mesh wire spacing, thickness of the insulating elastomer layer, and heating power. Response parameters of interest include effective folding angle, maximum von Mises stress in the SMA, maximum temperature in the SMA, maximum temperature in the elastomer, and radius of curvature at the fold line. We identify an optimized physical realization for maximizing folding capability under mechanical and thermal failure constraints. Furthermore, we conclude that the proposed self-folding system is capable of achieving folds of significant magnitude (as measured by the effective folding angle) as required to create useful 3D structures.

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Low Velocity Impact Performance Analysis of Fiber Composite Structure Embedded with Shape Memory Alloy

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES AEROSPACE TECHNOLOGY JAPAN ◽

10.2322/tastj.12.pc_35 ◽

2014 ◽

Vol 12 (ists29) ◽

pp. Pc_35-Pc_41

Author(s):

Ying-Chih LIN ◽

Yu-Liang CHEN ◽

Hung-Wen CHEN

Keyword(s):

Performance Analysis ◽

Shape Memory Alloy ◽

Shape Memory ◽

Composite Structure ◽

Fiber Composite ◽

Low Velocity Impact ◽

Low Velocity ◽

Velocity Impact ◽

Impact Performance

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Multiaxial low-cycle fatigue failure mechanism of super-elastic NiTi shape memory alloy micro-tubes

Materials Science and Engineering A ◽

10.1016/j.msea.2016.04.019 ◽

2016 ◽

Vol 665 ◽

pp. 17-25 ◽

Cited By ~ 11

Author(s):

Di Song ◽

Guozheng Kang ◽

Qianhua Kan ◽

Chao Yu ◽

Chuanzeng Zhang

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Failure Mechanism ◽

Fatigue Failure ◽

Low Cycle Fatigue ◽

Niti Shape Memory Alloy ◽

Cycle Fatigue

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Impact response of a low-cost randomly oriented fiber foam core sandwich panel

Journal of Composite Materials ◽

10.1177/0021998318764009 ◽

2018 ◽

Vol 52 (25) ◽

pp. 3429-3444 ◽

Cited By ~ 3

Author(s):

Ezequiel Buenrostro ◽

Daniel Whisler

Keyword(s):

Mechanical Properties ◽

Sandwich Panel ◽

Low Cost ◽

Three Dimensional ◽

Cost Effective ◽

Foam Core ◽

Fiber Reinforced ◽

Manufacturing Method ◽

Manufacturing Techniques ◽

The Impact

Three-dimensional fiber-reinforced foam cores may have improved mechanical properties under specific strain rates and fiber volumes. But its performance as a core in a composite sandwich structure has not been fully investigated. This study explored different manufacturing techniques for the three-dimensional fiber-reinforced foam core using existing literature as a guideline to provide a proof of concept for a low-cost and easily repeatable method comprised of readily available materials. The mechanical properties of the fiber-reinforced foam were determined using a three-point bend test and compared to unreinforced polyurethane foam. The foam was then used in a sandwich panel and subjected to dynamic loading by means of a gas gun (103 s−1). High-strain impact tests validated previously published studies by showing, qualitatively and quantitatively, an 18–20% reduction in the maximum force experienced by the fiber-reinforced core and its ability to dissipate the impact force in the foam core sandwich panel. The results show potential for this cost-effective manufacturing method to produce an improved composite foam core sandwich panel for applications where high-velocity impacts are probable. This has the potential to reduce manufacturing and operating costs while improving performance.

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Ni-Ti Shape Memory Alloy Coatings for Structural Applications: Optimization of HVOF Spraying Parameters

Advances in Materials Science and Engineering ◽

10.1155/2018/7867302 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10 ◽

Cited By ~ 4

Author(s):

Carmen De Crescenzo ◽

Despina Karatza ◽

Dino Musmarra ◽

Simeone Chianese ◽

Theocharis Baxevanis ◽

...

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Large Scale ◽

Thermal Spray Technology ◽

Spray Parameters ◽

Hvof Spraying ◽

Structural Applications ◽

External Stimuli ◽

Steel Substrates ◽

The Impact

This work aims at contributing to the development of a revolutionary technology based on shape memory alloy (SMA) coatings deposited on-site to large-scale metallic structural elements, which operate in extreme environmental conditions, such as steel bridges and buildings. The proposed technology will contribute to improve the integrity of metallic civil structures, to alter and control their mechanical properties by external stimuli, to contribute to the stiffness and rigidity of an elastic metallic structure, to safely withstand the expected loading conditions, and to provide corrosion protection. To prove the feasibility of the concept, investigations were carried out by depositing commercial NiTinol Ni50.8Ti (at.%) powder, onto stainless steel substrates by using high-velocity oxygen-fuel thermal spray technology. While the NiTinol has been known since decades, this intermetallic alloy, as well as no other alloy, was ever used as the SMA-coating material. Due to the influence of dynamics of spraying and the impact energy of the powder particles on the properties of thermally sprayed coatings, the effects of the main spray parameters, namely, spray distance, fuel-to-oxygen feed rate ratio, and coating thickness, on the quality and properties of the coating, in terms of hardness, adhesion, roughness, and microstructure, were investigated.

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