Condition monitoring of crack extension in the reinforcement adhesive joints by carbon nanotubes

Carbon nanotubes (CNT) are ideally suited to be employed for damage sensing in fiber rein- forced composite structures. In this work, the capability of CNTs for crack extension of a single lap Al-Al adhesive joints (SLJ) under shear load is studied using electrical resistance change. Different weight per- cent of CNT are added to epoxy adhesive. Epoxy adhesive with high concentration of CNT is obtained during shear loading to have the maximum strength and provide the best sensory properties. To provide a more concise evaluation of the crack extension in the adhesive layer under shear load, artificial defects are embedded into the SLJ specimens. The effects of square and circular defects with two different sizes on the crack extension in the adhesive layer are evaluated. The results showed that the maximum relative resistance change has occurred by 220% when the microcracks are initiated and accordingly developed from the nanoadhesive and changed its direction from the Square defect boundary. Additionally, in comparison with interface fracture in defective adhesive joint, when a part of crack grows through the adhesive layer, the resistance change showed higher values.

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Synergetic effects of carbon nanotubes and triblock copolymer on the lap shear strength of epoxy adhesive joints

Composites Part B Engineering ◽

10.1016/j.compositesb.2019.107457 ◽

2019 ◽

Vol 178 ◽

pp. 107457 ◽

Cited By ~ 6

Author(s):

Panta Jojibabu ◽

Y.X. Zhang ◽

Andrew N. Rider ◽

John Wang ◽

B. Gangadhara Prusty

Keyword(s):

Carbon Nanotubes ◽

Shear Strength ◽

Triblock Copolymer ◽

Epoxy Adhesive ◽

Adhesive Joints ◽

Lap Shear Strength ◽

Synergetic Effects ◽

Lap Shear

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Resistance Spot Weld assisted with Adhesive Bonding

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.d5188.118419 ◽

2019 ◽

Vol 8 (4) ◽

pp. 6978-6982

Keyword(s):

Spot Welding ◽

Adhesive Bonding ◽

Sheet Thickness ◽

Adhesive Layer ◽

Epoxy Adhesive ◽

Adhesive Joints ◽

Spot Weld ◽

Low Carbon ◽

Weld Bonding ◽

Resistance Spot

This paper presents an experimental investigation of the weld bonding of low carbon steel (JIS G3141) together with adhesive layers to increase the mechanical properties of weld bonding. Epoxy adhesive was used in this research applied on the sheet thickness of 1.2 mm. The weld-bonding was carried out by applying layer of adhesive followed by resistance spot welding on surface samples. The relative properties and characteristics of the resulting weld-bonded-adhesive joints are evaluated and compared with the conventional spot-welding through tensile-shear, peel, hardness tests and macro-etching observations. The strength of weld bond joints was calculated and compared with those in as-weld and adhesive-bond joints. Results showed that the strength of weld-bond adhesive is higher than as-weld specimen. The hardness distribution of weld bond adhesive joints was investigated, at three regions i.e. base metal (BM), the heat-affected zone (HAZ), and the fusion zone (FZ) using micro-hardness Vickers machine. It can conclude that the presence of adhesive does not affect the hardness of weld-bonded. From macro- etching observation, the layer adhesive influenced the weld bond via the size nugget of weld-bonded which is smaller than as-weld. The introduction of adhesive layer in spot welding improves the joint strength and quality of spot weld.

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The effect of metallic fiber geometry and multi-walled carbon nanotubes on the mechanical behavior of aluminum fiber-reinforced composite adhesive joints

Proceedings of the Institution of Mechanical Engineers Part L Journal of Materials Design and Applications ◽

10.1177/1464420720981404 ◽

2020 ◽

pp. 146442072098140

Author(s):

Maryam Khayamdar ◽

Hadi Khoramishad

Keyword(s):

Carbon Nanotubes ◽

Mechanical Response ◽

Adhesive Layer ◽

Adhesive Joints ◽

Fiber Reinforced ◽

Fiber Reinforced Composite ◽

Reinforced Composite ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes ◽

Aluminum Fiber

The effect of the geometry of metallic fibers on the mechanical response of aluminum fiber-reinforced composite adhesive joints was studied experimentally. Moreover, a combination of multi-walled carbon nanotubes and aluminum fibers was used for reinforcing the composite adhesive joints. Different geometries for the aluminum fibers including straight, twisted and spring-shaped with different pitch lengths were considered. The results indicated that the composite adhesive joints reinforced with a combination of multi-walled carbon nanotubes and aluminum fibers experienced the highest improvement of 171% in the strength compared to the unreinforced specimen. It was found out that the aluminum fiber geometry can significantly influence the adhesive joint behavior. Incorporating the twisted aluminum fibers into the adhesive layer increased, while the spring-shaped fibers decreased the strength of the composite adhesive joints compared to the straight aluminum fibers. The fracture surfaces of the composite adhesive joints were analyzed using scanning electron microscope.

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Improvement of mechanical properties in epoxy adhesive joints of Al alloy via carbon nanotubes from flame

Materials Research Express ◽

10.1088/2053-1591/ab25c2 ◽

2019 ◽

Vol 6 (8) ◽

pp. 0850d7 ◽

Cited By ~ 1

Author(s):

Pu Zhao ◽

Xuhai Xiong ◽

Rong Ren ◽

Zhongbao Zhang ◽

Xu Cui ◽

...

Keyword(s):

Mechanical Properties ◽

Carbon Nanotubes ◽

Epoxy Adhesive ◽

Adhesive Joints ◽

Al Alloy

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Strengthening and repairing of engineered bamboo-steel epoxy adhesive joints with carbon nanotube on the basis of resin pre-coating method

European Journal of Wood and Wood Products ◽

10.1007/s00107-020-01512-1 ◽

2020 ◽

Author(s):

Wen Liu ◽

Hang Xu ◽

Xiaozhi Hu ◽

Bingyan Yuan ◽

Bo Tan ◽

...

Keyword(s):

Carbon Nanotube ◽

Epoxy Adhesive ◽

Adhesive Joints ◽

Coating Method

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Bond Thickness Effects upon Dynamic Behaviour in Adhesive Joints

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.97-101.3920 ◽

2010 ◽

Vol 97-101 ◽

pp. 3920-3923 ◽

Cited By ~ 7

Author(s):

Xiao Cong He

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Dynamic Behaviour ◽

Adhesive Layer ◽

Adhesive Joints ◽

Response Functions ◽

Frequency Range ◽

Element Analysis ◽

Cantilevered Beam ◽

Different Thickness

The influence of adhesive layer thickness on the dynamic behaviour of the single-lap adhesive joints is investigated in this paper. The ABAQUS finite element analysis (FEA) software was used to predict the frequency response functions (FRFs) of the single-lap adhesive joints of different thickness of the adhesive layer. As a reference, the FRFs of a cantilevered beam without joint were investigated as well. It is clear that the FRFs of the four beams are close to each other within the frequency range 0~1000 Hz. It is also found that the composite damping of the single-lap adhesive joint increases as the thickness of the adhesive layer increases.

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