scholarly journals Effect of Holes in Overlap on the Load Capacity of the Single-Lap Adhesive Joints Made of EN AW-2024-T3 Aluminium Alloy

2021 ◽  
Vol 21 (4) ◽  
pp. 112-121
Author(s):  
Władysław Zielecki ◽  
Katarzyna Burnat ◽  
Andrzej Kubit ◽  
Tomáš Katrňák
Keyword(s):  
Load Capacity ◽  
Epoxy Adhesive ◽  
Lap Joints ◽  
Adhesive Joints ◽  
Front Part ◽  
Tensile Shear ◽  
Static Tests ◽  
Structural Modifications ◽  
Structural Adhesive ◽  
Strength Of Adhesive Joints

Abstract The paper presents the results of experimental research aimed at determining the possibilities of strengthening structural adhesive joints. Techniques to improve the strength of adhesive joints was to make holes in the front part of the adherends in order to make the joint locally more flexible in the area of stress concentration at the joint edges. The tests were carried out for the lap joints of EN AW-2024-T3 aluminum alloy sheets, which were bonded with Loctite EA3430 epoxy adhesive. Static tests were carried out on the basis of the tensile/shear test. It has been shown that the applied structural modifications allow for an increase in the strength of the joint, in the best variant, an increase in strength of 14.5% was obtained. In addition, it has been shown that making holes in the adherends allows to reduce the spread of strength results.

Effects of Surface Treatment and Loading Speed on Adhesive Strength of Aluminum to Polycarbonate Lap Joints

2004 ◽  
Vol 261-263 ◽  
pp. 405-410 ◽  
Author(s):  
Do Won Seo ◽  
Ho Chel Yoon ◽  
J.Y. Lee ◽  
Jae Kyoo Lim
Keyword(s):  
Surface Roughness ◽  
Shear Strength ◽  
Surface Treatment ◽  
Adhesive Strength ◽  
Lap Joints ◽  
Adhesive Joints ◽  
Tensile Shear Strength ◽  
Tensile Shear ◽  
Mechanical Removal ◽  
Strength Of Adhesive Joints

The bonding strength of adhesive joints is influenced by the surface roughness of the joining parts. However, the magnitude of the influence has not yet been clarified because of the complexity of the phenomena. In this study, it is showed that surface treatment affects adhesive strength and durability of aluminum/polycarbonate single-lap joints, and loading speed affects tensile-shear strength of adhesive joints. To evaluate the effect of surface treatments on the adhesive strength, several surface treatment methods are used, that is, cleaning, grinding, SiC polishing and sand blasting. It is showed that an optimum value of the surface roughness exists with respect to the tensile-shear strength of adhesive joints. The adhesive strength shows linear relationship with the surface roughness and loading speed. And the mechanical removal of disturbing films of lubricants, impurities and oxides make adhesive strength increase significantly.

scholarly journals Strength and Failure Mechanism of Composite-Steel Adhesive Bond Single Lap Joints

2018 ◽  
Vol 2018 ◽  
pp. 1-10
Author(s):  
Kai Wei ◽  
Yiwei Chen ◽  
Maojun Li ◽  
Xujing Yang
Keyword(s):  
Failure Mechanism ◽  
Shear Failure ◽  
Failure Load ◽  
Lap Joints ◽  
Adhesive Joints ◽  
Adhesive Failure ◽  
Interface Failure ◽  
Element Analysis ◽  
Single Lap Joints ◽  
Structural Adhesive

Carbon fiber-reinforced plastics- (CFRP-) steel single lap joints with regard to tensile loading with two levels of adhesives and four levels of overlap lengths were experimentally analyzed and numerically simulated. Both joint strength and failure mechanism were found to be highly dependent on adhesive type and overlap length. Joints with 7779 structural adhesive were more ductile and produced about 2-3 kN higher failure load than MA830 structural adhesive. Failure load with the two adhesives increased about 147 N and 176 N, respectively, with increasing 1 mm of the overlap length. Cohesion failure was observed in both types of adhesive joints. As the overlap length increased, interface failure appeared solely on the edge of the overlap in 7779 adhesive joints. Finite element analysis (FEA) results revealed that peel and shear stress distributions were nonuniform, which were less severe as overlap length increased. Severe stress concentration was observed on the overlap edge, and shear failure of the adhesive was the main reason for the adhesive failure.

Experimental Assessment of the Dynamic Behavior of Polyolefin Thermoplastic Hot Melt Adhesive

2018 ◽  
Author(s):  
Raffaele Ciardiello ◽  
Andrea Tridello ◽  
Luca Goglio ◽  
Giovanni Belingardi
Keyword(s):  
Failure Modes ◽  
Industrial Applications ◽  
Lap Joints ◽  
Adhesive Joints ◽  
Dynamic Tests ◽  
Cohesive Failure ◽  
Static Tests ◽  
Piping Systems ◽  
The Many ◽  
Hot Melt

In the last decades, the use of adhesives has rapidly increased in many industrial fields. Adhesive joints are often preferred to traditional fasteners due to the many advantages that they offer. For instance, adhesive joints show a better stress distribution compared to the traditional fasteners and high mechanical properties under different loading conditions. Furthermore, they are usually preferred for joining components made of different materials. A wide variety of adhesives is currently available: thermoset adhesives are generally employed for structural joints but recently there has been a significant increment in the use of thermoplastic adhesives, in particular of the hot-melt adhesives (HMAs). HMAs permit to bond a large number of materials, including metal and plastics (e.g., polypropylene, PP), which can be hardly bonded with traditional adhesives. Furthermore, HMAs are characterized by a short open time and, therefore, permit for a quick and easy assembly process since they can be easily spread on the adherend surfaces by means of a hot-melt gun and they offer the opportunity of an ease disassembling process for repair and recycle. For all these reasons, HMAs are employed in many industrial applications and are currently used also for bonding polypropylene and polyolefin piping systems. In the present paper, the dynamic response of single lap joints (SLJ) obtained by bonding together with a polyolefin HMA two polypropylene substrates was experimentally assessed. Quasi-static tests and dynamic tests were carried out to investigate the strain rate effect: dynamic tests were carried out with a modified instrumented impact pendulum. Relevant changes in the joint performance have been put in evidence. Failure modes were finally analysed and compared. A change in the failure mode is experimentally found: in quasi-static tests SLJ failed due to a cohesive failure of the adhesive, whereas in dynamic tests the SLJ failed due to an interfacial failure, with a low energy absorption.

Strength of Adhesive Joints Under Impact Stress Conditions

2006 ◽  
Author(s):  
Luca Goglio ◽  
Massimo Rossetto
Keyword(s):  
Epoxy Adhesive ◽  
Structural Stress ◽  
Bonded Joints ◽  
Tensile Shear ◽  
Impact Stress ◽  
Steel Strips ◽  
Dynamic Loading Condition ◽  
The Impact ◽  
Stress Combinations ◽  
Strength Of Adhesive Joints

The paper reports an experimental study on the bonded joints, carried out by means of an instrumented impact pendulum, equipped to load overlap specimens in tensile shear. Such testing configuration is the most adequate and natural to study the possible modifications of the behavior of the joint, changing from static to dynamic loading condition, keeping the same specimen type. The specimens were steel strips bonded by an epoxy adhesive (Hysol 3425). Several values of lap length, adhesive and adherends thickness were adopted, to achieve rupture under different stress combinations. The stress state at rupture has been calculated by means of a structural solution. The results show that it is possible to represent the failure condition on a chart having as axes the peel and shear structural stress, in a way similar to that found for static cases. Furthermore, in spite of the concerns associated with the impact condition, the strength of the adhesive does not decrease with respect to the case of static loading.

The Research of Adhesively-Bond of Paster Single Lap Joints on Strength Based on ANSYS

2013 ◽  
Vol 785-786 ◽  
pp. 1236-1239
Author(s):  
Yu Qi Wang ◽  
Xiao Cong He ◽  
Bao Ying Xing ◽  
Sen Zhou
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Adhesive Bond ◽  
Lap Joints ◽  
Adhesive Joints ◽  
Single Lap Joints ◽  
Strength Based ◽  
Strength Of Adhesive Joints ◽  
Element Method

The adhesive-bond of paster single lap joints was put forward firstly. The strength of 5052Al-Al adhesive-bond of single lap joints (SLJ) and 5052Al-Al paster adhesive-bond of SLJ were investigated using finite element method (FEM). Results from the simulation showed that the paster adhesive-bond of SLJ was stronger than the adhesive-bond of SJL. So it can use the paster adhesive joints to improve the strength of adhesive joints.

Overview of different strength prediction techniques for single-lap bonded joints

2016 ◽  
Vol 231 (1-2) ◽  
pp. 210-223 ◽  
Author(s):  
CCRG de Sousa ◽  
RDSG Campilho ◽  
EAS Marques ◽  
M Costa ◽  
LFM da Silva
Keyword(s):  
Analytical Methods ◽  
Accurate Method ◽  
Epoxy Adhesive ◽  
Lap Joints ◽  
Adhesive Joints ◽  
Strength Prediction ◽  
Bonded Joints ◽  
Stress Concentrations ◽  
Single Lap Joints ◽  
Structural Applications

Adhesive joints have been used in several fields of engineering, and their applications are vast. Due to their easy and quick fabrication process, single-lap joints are a common configuration. The increase of strength, weight reduction and resistance to corrosion are some of the advantages of this kind of joint over traditional joining methods. However, stress concentrations at the overlap edges are one of the main disadvantages. There are very few accurate design techniques for the diversity of bonded joints that can be found in real applications, which constitutes an obstacle to the use of this bonding method in structural applications. This work aims at comparing different analytical and numerical methods in the strength prediction of single-lap joints with different overlap lengths ( LO). The main objective is to evaluate which predictive method is the best. Adhesive joints were produced between aluminium adherends using a brittle epoxy adhesive (Araldite® AV138), a moderately ductile epoxy adhesive (Araldite® 2015) and a ductile polyurethane adhesive (Sikaforce® 7888). Different analytical methods were considered, together with two numerical techniques: cohesive zone models (CZM) and the extended finite element method (XFEM), allowing the comparative analysis. The analytical methods showed that they only give relatively accurate results in very specific conditions. The CZM analysis with the triangular law revealed to be a very accurate method, with the exception of joints with very ductile adhesives. On the other hand, the XFEM analysis was not adequate, especially for crack growth in mixed mode.

scholarly journals Effect of the Application of Different Surface Treatment Methods on the Strength of Titanium Alloy Sheet Adhesive Lap Joints

Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4173 ◽  
Author(s):  
Anna Rudawska ◽  
Kazimierz Zaleski ◽  
Izabela Miturska ◽  
Agnieszka Skoczylas
Keyword(s):  
Titanium Alloy ◽  
Surface Treatment ◽  
Shot Peening ◽  
Hardness Test ◽  
Epoxy Adhesive ◽  
Alloy Sheet ◽  
Lap Joints ◽  
Adhesive Joints ◽  
Test Method ◽  
Treatment Methods

This study investigated the effect of the different surface treatment methods on the strength of Ti6Al4V titanium alloy sheet adhesive joints. The following surface treatment methods were used: alkaline degreasing, anodizing, vibratory shot peening, and anodizing with vibrational shot peening. The following tests/measurements were carried out during the experiment: surface roughness measurements; microhardness measurements (conducted by the Vickers hardness test method); and strength tests of single-lap adhesive joints fabricated with the use of two epoxy adhesives, rigid and flexible, both based on epoxy resin Epidian 5. It has been found that the application of anodizing followed by vibratory shot peening leads to increased strength of adhesive joints, irrespective of the type of applied epoxy adhesive.

Method for creating of laminated wood high strength

2015 ◽  
Vol 5 (4) ◽  
pp. 145-151
Author(s):  
Попов ◽  
Viktor Popov ◽  
Латынин ◽  
Andrey Latynin
Keyword(s):  
Magnetic Field ◽  
Field Intensity ◽  
Magnetic Field Intensity ◽  
High Strength ◽  
Adhesive Joints ◽  
Tensile Shear ◽  
Oak Wood ◽  
Ultrasonic Oscillations ◽  
Increased Strength ◽  
Strength Of Adhesive Joints

Propose a method of producing laminated wood with glued connection of increased strength of the adhesive by modifying the influence of a combined physical field. On a special installation, allowing you to create magnetic field up to 24∙104 A/m and ultrasound with frequency up to 22 KHz, transactions on effects of adhesive CFG a combo box. Experimentally the increase of the tensile shear adhesive joints of oak wood and birch. The increase in magnetic field intensity and frequencies of ultrasonic oscillations is accompanied by an increase of the strength of adhesive joints.

Technical Evaluation of Structural Adhesive Joints under Adverse Operation Conditions

2014 ◽  
Vol 797 ◽  
pp. 169-174
Author(s):  
José M. Arenas Reina ◽  
Rosa Ocaña López ◽  
Cristina Alía García ◽  
Julián J. Narbón Prieto
Keyword(s):  
Mechanical Properties ◽  
Adhesive Joint ◽  
Epoxy Adhesive ◽  
Adhesive Joints ◽  
Accelerated Ageing ◽  
Motor Oil ◽  
Aluminum Composite ◽  
Operation Conditions ◽  
Structural Adhesive ◽  
Better Than

This work analyzes the degradation of aluminum-composite adhesive joints under the action of water and motor oil. For this purpose, we have performed an accelerated ageing of the adhesive joint by immersion in water and oil. Likewise, we have evaluated the loss of mechanical properties that aging causes into adhesive joint. First, tests have been performed with bulk adhesive specimens (epoxy and polyurethane) immersed in water and motor oil during independent periods of time (1 at 128 days) in order to study the diffusion of water and motor oil into the adhesive. Second, we have evaluated the loss of mechanical properties that aging causes in the adhesive joint. Tests conclusions show that water degrades the adhesive more than motor oil. Additionally and under the action of water and motor oil, polyurethane adhesive joints retain their mechanical properties better than epoxy adhesive joints.

Failure Analysis of Composite-Based Lightweight Multimaterial Joints in Tensile-Shear Tests After Cyclic Heat at High-Relative Humidity

2016 ◽  
Vol 139 (4) ◽  
Author(s):  
Kaori Sakai ◽  
Sayed A. Nassar
Keyword(s):  
Relative Humidity ◽  
Failure Analysis ◽  
Load Transfer ◽  
Epoxy Adhesive ◽  
Lap Joints ◽  
High Relative Humidity ◽  
Published Data ◽  
Tensile Shear ◽  
Bonded Composite ◽  
Cyclic Heat

Failure analysis of tensile-shear tested bonded composite-based single lap joints (SLJs) that have been subjected to two different levels of cyclic environmental loading is provided. Each test joint has at least one composite adherend which is made of glass fiber-reinforced polymer (GFRP); the second adherend may be aluminum, magnesium, or GFRP composite, and structural epoxy adhesive is used to join two adherends together for creating test joints. Scanning electron microscope (SEM) and energy dispersive spectrometry (EDS) are utilized to investigate the root cause failure of fractured surfaces that gives an insight into the recently published data that showed a significant effect of the cyclic heat on the static load transfer capacity (LTC) of the same SLJs. The SEM and EDS inspections show that the failure mode shifts from interfacial adhesive failure (ADH) to fiber tear (FT) for the GFRP/GFRP joints that have been exposed to cyclic heat with and without high relative humidity as compared to that at ambient condition. Further, failure analysis and discussion are provided.

Sign in / Sign up

Export Citation Format

Share Document