Research on strength of nanocomposite adhesively bonded composite joints (original) (raw)
Related papers
Composites Part B: Engineering, 2017
Especially findings from nanoscience and nanotechnology, which have progressed significantly in recent years, influence materials and mechanical sciences deeply as well as other disciplines. In this study, the failure loads of single-lap joints (bonding joints used in space, automotive and aerospace applications) bonded by a nanocomposite adhesive e obtained by adding nanostructure to the adhesive e were experimentally examined to increase the failure load of adhesively bonded joints. Adhesively bonded single-lap joints were produced using DP460 toughened adhesive type, DP270 rigid adhesive type and DP125 flexible adhesive type as the adhesives; AA2024-T3 aluminum alloy was used as the adherend, and Graphene-COOH, Carbon Nanotube-COOH and Fullerene C60 were used as the added nanostructures. Furthermore, to examine the effects of nanostructure reinforcement ratios in the adhesive at joint-failure load, three nanostructures with different ratios of 0.25%, 0.5%, 1%, 2% and 3% were added. As a result, when the experimental failure loads were examined, the nanocomposite adhesives obtained by adding nanostructure were found to have increased the load failure of the joint. However, increase rate in the failure load changes depending on the structural features of the adhesive and the type of nanostructure. Moreover, in the geometries of single-lap joints produced in this study, the best nanostructure reinforcement ratio, in terms of the failure load of the joint, was 1% percent by weight.
Composites Part B: Engineering, 2016
This study experimentally determines the tensile failure load of the nanocomposite adhesive-obtained by adding nanostructures to the adhesive-using four different methods in singlelap joints. For the study, adhesively bonded single-lap joints were produced by using DP460 liquid structural epoxy as the adhesive, AA2024-T3 aluminum alloy as the adherend and graphene as the nanostructure. When the failure load obtained from the experiments was examined, it was seen that, while the nanostructure-reinforced methods indicated in the literature have a great effect on the failure load of the joint and the standard deviation, a new method developed in this study increased the failure load of the joint and minimized the standard deviation. These improvements increased the reliability and reproducibility of the joint.
Reviews of Adhesion and Adhesives, 2020
The aim of this study is to present an efficient and effective technique to strategically investigate and classify the influence of a set of manipulated parameters that affect the mechanical properties and performance of adhesively bonded joints formed by an adhesive that is reinforced by various types of carbon nanoparticles (NPs). Specifically, single-lap joints (SLJs) are considered in this study. The selected parameters include the adherend types (i.e., carbon fiber-reinforced polymers (CFRPs) and glass fiber-reinforced polymers (GFRPs)), three types of nanoparticles (i.e., carbon nanofibers (CNFs), multi-walled carbon nanotubes (MWCNTs) and graphene nanoplatelets (GNPs)), different weight-percent (wt.%) of GNPs (i.e., 0, 0.5, 1%), and three different strain (or loading) rates, classified as static, quasi-static and impact loadings, herein. The study employed two mixed-level full factorial design of experiments (DOE) to evaluate the contribution of the aforementioned parameters,...
Engineering Fracture Mechanics, 2018
In our earlier paper [Srivastava et al. Eng. Fract Mech, 180 (2017)] we found that mode I, mode II fracture toughness of carbon nanotubes (CNTs) filled woven carbon fabric composites increases with the addition of nanofillers. In order to prove the effect of nanofillers on adhesively bonded joints of woven carbon fabric laminates, the present study is conducted under double cantilever beam (DCB), end notched flexural (ENF) and single lap shear (SLS) tests. Graphene nanoplates (GnPs) filled epoxy resin, and carbon blacks (CBs) filled epoxy resin, and pure epoxy resin adhesives were used to prepare the DCB, ENF and single lap adhesively bonded joint specimen from two similar woven carbon fabric composite plates to measure them. Fracture toughness (mode I mode II) and shear strength of adhesively bonded joints were determined. The results show that the adhesively bonded woven carbon fabric composite joints with GnPsfilled epoxy resin and CBs-filled epoxy resin adhesives give better fracture toughness mode I, mode II and shear strength compare to pure epoxy resin adhesively bonded composite specimen. Mode I value is lower than mode II value due to the sharp propagation of cracks under tensile stress. Scanning electron microscopy (SEM) was utilized to monitor the distribution of nanofillers within the adhesively bonded texture to examine the effect of fracture surfaces in the bonded DCB, ENF and single lap shear joint specimens respectively.
Experimental characterization and numerical modelling analyses of nano-adhesive-bonded joints
Experimental and numerical characterizations of nano-adhesive-bonded joints typically used in aerospace applications are presented. First, samples of single-lap joints produced using a composite reinforced with carbon fibre fabric (2% graphene by weight), were analysed. Five samples were produced by injecting nanostructure particles in the epoxy resin and five are not (non-reinforced resin). Shear tests were performed to measure the resistances of the bonded joints, to assess the structural performances of the structures with and without the resin. Second, finite-element numerical models were applied based on experiments on adhesive joints; in particular a numerical simulation of the adhesive lap-joint model was performed using ANSYS software. Analyses were performed for the joints with unfilled and nanofilled adhesive, focusing on the cooling process during which adhesive single-lap joints are mainly generated. The experimental and numerical model results generally agree quite well. Graphene increased the stiffness of each lap joint under a rational load charge. The nanostructure adhesive increased the failure load, but this increase depended on various parameters, including adhesive structural features and the structures of the nanostructures produced. The reinforced adhesive nanostructure was found to decrease the weight.
Improving composites single-lap joint performance by carbon nanotubes
Procceedings of the 24th ABCM International Congress of Mechanical Engineering, 2017
This paper presents a comparison between strength of adhesively bonded single lap joint with and without addition of Multiwall Carbon Nanotubes(MWCNT) in adhesive. Shear strength analysis of adhesively bonded single lap joint is done applying pulling load which produces shear stress at overlap between two substrates which joined together by using adhesive. Al-Al substrates were used and as per ASTM standard single lap joints are prepared. Various specimens were prepared by changing overlap and thickness of substrates. Four tests were carried out for each specimen with change in overlap and thickness of Al-Al substrates with and without addition of MWCNT in adhesive. Araldite AW 106, Hardener HV 953 used as adhesive,it has various properties and used as per their data sheet and processing given by respective company. The result of the comparative strength analysis of adhesively bonded single lap joint is presented and on the basis of experimental observation it is clear that MWCNT filled epoxy resin gives higher bonding strength than unfilled epoxy resin bonded substrates.
EEFECT OF NANO FILLER ADHESIVE IN SINGLE LAP JOINT BONDED STRUCTURES
This work focuses on developing new adhesive formulations based on epoxy/nanostructures carbon forms. Different types of Nano fillers were dispersed in an epoxy matrix for developing toughened epoxy paste aeronautic adhesives. The reinforced adhesives were used for bonding glass fiber/epoxy composite adherents. Data were also compared to the result obtained both for the unfilled adhesive and/or adherents. Single lap joint sample were prepared to measure mechanical strength and adhesion properties of the joint configurations to analyze the types of failure mode using Acoustic emission testing.
Ijriet Eefect of Nano Filler Adhesive in Single Lap Joint Bonded Structures
2016
This work focuses on developing new adhesive formulations based on epoxy/nanostructures carbon forms. Different types of Nano fillers were dispersed in an epoxy matrix for developing toughened epoxy paste aeronautic adhesives. The reinforced adhesives were used for bonding glass fiber/epoxy composite adherents. Data were also compared to the result obtained both for the unfilled adhesive and/or adherents. Single lap joint sample were prepared to measure mechanical strength and adhesion properties of the joint configurations to analyze the types of failure mode using Acoustic emission testing.
International Journal of Adhesion and Adhesives, 2023
Today, composite materials are frequently used as materials in engineering due to their light weight and strength. Studies on the use of composite materials and the adhesively bonded joints used to bond these materials are of importance. In general, studies on the bonding method with adhesives are concerned with the strength of the joint. In this study, fiber fabric was reinforced to the bonding area in order to increase the strength of the bonding connections used in the aviation and automotive fields. DP460 structural adhesive as adhesive and AA2024-T3 aluminum alloy used in aviation field as bonded material were used to produce a single-lap joint bonded with adhesive. In addition, carbon fiber, glass fiber and aramid fiber fabric were used as reinforcing elements in the adhesive zone. Furthermore, to examine the effects of fiber fabric length in the overlap area at joint-failure load, four different length fiber fabric such as 100%, 80%, 40% and 20% of the overlap length were added. As a result, when the experimental failure loads were examined, the composite adhesive obtained by adding fibrous fabric has been found to increase the load failure of the joint between about 16% and 90%. However, increase rate in the failure load changes depending on the length fiber fabric and the type of fiber fabric. Moreover, in the geometries of single-lap joints produced in this study, the best fiber fabric type, in terms of the failure load of the joint, was carbon fiber fabric.