Influence of cork microparticles on the fracture type in single lap joints

2020 ◽  
pp. 095440622093672
Author(s):  
CI da Silva ◽  
AQ Barbosa ◽  
RJC Carbas ◽  
EAS Marques ◽  
A Akhavan-Safar ◽  
...  
Keyword(s):  
Failure Mode ◽  
Automotive Industry ◽  
Adhesive Bonding ◽  
Low Cost ◽  
High Strength ◽  
Industrial Applications ◽  
Epoxy Adhesive ◽  
Lap Joints ◽  
Fracture Type ◽  
Single Lap Joints

Over the years, the use of structural adhesive bonding has significantly grown in numerous technological sectors, including the aeronautical, aerospace, medical and automotive industries. The growing need to design lighter and better performing structures has pushed designers to improve their construction techniques, and consequently adhesive joints have appeared as an optimal joining solution, providing the necessary high strength and stiffness, low cost and excellent capabilities to join multi-material structures. In many of these applications, perhaps most importantly in the automotive industry, it is fundamental to ensure that when the joint is loaded to destruction, such as in a vehicle collision, failure is always cohesive and adhesive failure is avoided. This work proposes a novel technique to ensure that the failure mode is not adhesive, forcing a failure mode that does not propagate through or near the interface. To accomplish that, an epoxy adhesive typically used in the automotive industry was studied and reinforced with microparticles of cork. This study was validated experimentally with joint configurations typical of industrial applications, such as single lap joints, supported by numerical simulations performed to better understand the failure mechanism. The influence of the amount and size of these particles on the fracture type was evaluated. Overall, both the experimental and numerical results showed that by increasing both the size and the amount of the particles in the adhesive, the failure mode tends to be more cohesive (in the middle of the bondline) with a small reduction in joint strength, demonstrating that this can be a viable technique if cohesive failures in the adhesive layers are necessary.

Experimental and numerical study of the dynamic response of an adhesively bonded automotive structure

2020 ◽  
Vol 234 (14) ◽  
pp. 3385-3397
Author(s):  
NDD Silva ◽  
JJM Machado ◽  
EAS Marques ◽  
PMGP Moreira ◽  
LFM da Silva
Keyword(s):  
Adhesive Bonding ◽  
Numerical Study ◽  
Low Cost ◽  
High Strength ◽  
Epoxy Adhesive ◽  
Lap Joints ◽  
Impact Response ◽  
Vehicle Body ◽  
Component Level ◽  
The Impact

Based on economic and environmental factors related to energy efficiency, the automotive industry is being increasingly encouraged to design lighter structures, making use of adhesive bonding in vehicle body frames. To meet the standards of the automotive sector, adhesive joints must provide high strength and stiffness, low cost and good energy absorption at a component level, thereby ensuring good impact strength and passenger safety. This work aims to study, at room temperature (24°C), the impact response of a real scale automotive structure bonded with a crash-resistant epoxy, allowing to access the suitability of adhesives for automotive structural purposes. The epoxy adhesive was found to successfully transfer the loads to the aluminium substrates and not to compromise the integrity of the structure, as its failure was dominated by the behaviour of aluminium. Results obtained with a numerical model of the component were found to be in close agreement with the experimental failure load, demonstrating that numerical analysis can be a viable tool to predict the structure’s behaviour. In addition, a polyurethane was used as an alternative to the epoxy system to bond the structure, proving that the joint behaves better in the presence of a more flexible adhesive, as no failure was found for this case. Aluminium single-lap joints with two adhesive thicknesses were tested as a complement to understand the influence of this parameter on the impact response of a joint, showing a 21% decrease in strength when the highest thickness was used.

SYNTHESIS AND CHARACTERISATION OF WOVENROVING GLASS MAT FOR EPOXYCOMPOSITES

2020 ◽  
Vol 15 (4) ◽  
Author(s):  
Mahesh Mallampati ◽  
Sreekanth Mandalapu ◽  
Govidarajulu C
Keyword(s):  
Tensile Strength ◽  
Glass Fiber ◽  
Low Cost ◽  
Weight Ratio ◽  
High Strength ◽  
Hardness Test ◽  
Industrial Applications ◽  
Sem Analysis ◽  
Low Thermal Expansion ◽  
Manufacturing Techniques

The composite materials are replacing the traditional materials because oftheir superior properties such as high tensile strength, low thermal expansion, high strength to weight ratio, low cost, lightweight, high specific modulus, renewability and biodegradability which are the most basic & common attractive features of composites that make them useful for industrial applications. The developments of new materials are on the anvil and are growing day by day. The efforts to produce economically attractive composite components have resulted in several innovative manufacturing techniques currently being used in the composites industry. Generally, composites consist of mainly two phases i.e., matrix and fiber. In this study, woven roving mats (E-glass fiber orientation (-45°/45°,0°/90°, - 45°/45°),UD450GSM)were cut in measured dimensions and a mixture of Epoxy Resin (EPOFINE-556, Density-1.15gm/cm3), Hardener (FINE HARDTM 951, Density- 0.94 gm/cm3) and Acetone [(CH3)2CO, M= 38.08 g/mol] was used to manufacture the glass fiber reinforced epoxy composite by hand lay-up method. Mechanical properties such as tensile strength, SEM analysis, hardness test, density tests are evaluated.

scholarly journals Advanced High Strength Steel in Auto Industry: an Overview

2014 ◽  
Vol 4 (4) ◽  
pp. 686-689 ◽  
Author(s):  
N. Baluch ◽  
Z. M. Udin ◽  
C. S. Abdullah
Keyword(s):  
Automotive Industry ◽  
High Strength Steel ◽  
Low Cost ◽  
High Strength ◽  
Direct Result ◽  
Advanced High Strength Steel ◽  
Geometrical Form ◽  
Cost Efficient ◽  
Safety Attributes ◽  
Selection Of

The world’s most common alloy, steel, is the material of choice when it comes to making products as diverse as oil rigs to cars and planes to skyscrapers, simply because of its functionality, adaptability, machine-ability and strength. Newly developed grades of Advanced High Strength Steel (AHSS) significantly outperform competing materials for current and future automotive applications. This is a direct result of steel’s performance flexibility, as well as of its many benefits including low cost, weight reduction capability, safety attributes, reduced greenhouse gas emissions and superior recyclability. To improve crash worthiness and fuel economy, the automotive industry is, increasingly, using AHSS. Today, and in the future, automotive manufacturers must reduce the overall weight of their cars. The most cost-efficient way to do this is with AHSS. However, there are several parameters that decide which of the AHSS types to be used; the most important parameters are derived from the geometrical form of the component and the selection of forming and blanking methods. This paper describes the different types of AHSS, highlights their advantages for use in auto metal stampings, and discusses about the new challenges faced by stampers, particularly those serving the automotive industry.

Advanced Joining Techniques in European Shipbuilding

2004 ◽  
Vol 20 (03) ◽  
pp. 200-210 ◽  
Author(s):  
Frank Roland ◽  
Luciano Manzon ◽  
Pentti Kujala ◽  
Markus Brede ◽  
Jan Weitzenbock
Keyword(s):  
Adhesive Bonding ◽  
High Strength ◽  
Industrial Applications ◽  
Future Research ◽  
Special Focus ◽  
Open Problems ◽  
Ongoing Research ◽  
Mechanical Joining ◽  
Laser Hybrid Welding ◽  
The Impact

Joining processes are an important key factor for the competitiveness of European shipbuilders. They not only represent a significant portion of the total man hour consumption in hull production and outfitting, but due to heat distortions they also have a significant impact on nonproductive work operations, such as straightening and fitting. Those operations can interfere with on-board outfitting and increase lead time and construction cost. In addition to their contribution to shipyard productivity, joining techniques have a significant impact on material properties and thus on product performance and quality. Those factors become increasingly important for complex structures using comparatively thin and high-strength materials. Considering the importance of efficient joining, European shipbuilders in the past decade have invested significant efforts to develop new joining techniques, such as laser welding, adhesive bonding, and mechanical joining. Based on research results, practical industrial applications have been developed recently. After reviewing the impact of joining processes on competitiveness, the article will summarize a number of past and ongoing research projects with special focus on design methods, process and equipment development, fatigue strength of joints, quality assurance, and approval. It will then present a number of recent applications of new joining techniques in European shipyards. Finally, open problems and future research needs will be briefly discussed. The article is based on a joint effort of leading European experts and will focus on laser and laser hybrid welding, adhesive bonding, and mechanical joining

Experimental investigation on adhesive bonding of similar and dissimilar weld joint used for automotive applications

2021 ◽  
pp. 095440892110631
Author(s):  
Rohit Verma ◽  
Lochan Sharma ◽  
Mayank Chauhan ◽  
Rahul Chhibber ◽  
Kanwer Singh Arora
Keyword(s):  
Tensile Strength ◽  
Failure Mode ◽  
Adhesive Bonding ◽  
Lap Joints ◽  
Mode Analysis ◽  
Dissimilar Joints ◽  
Bonding Parameters ◽  
Adhesion Failure ◽  
Failure Mode Analysis ◽  
Length Changes

The automobile industry has started using adhesive bonding to join load bearing components which aerospace industry has been using for decades. Adhesive lap joints are used frequently in the manufacture of automobile. In present study, structural adhesives were used to join the aluminium alloy (AA5083 H111) with the HSS dual phase (DP780) steel. Adhesive bonding appears to be one of the appropriate methods of joining dissimilar materials. The aim of this work is to analyze the tensile strength of similar and dissimilar joints. The influence of various parameters was also investigated such as the overlap length and the bondline thickness of specimens. In DP steel, there is 22% increase in strength for similar lap joint when overlap length changes from 10 mm to 15 mm, while there is 45% increase in strength when it varies from 15 mm to 20 mm. Similarly in case of Al alloy, there is 26% increased strength for similar lap joints when length varies from 10 mm to 15 mm, while it increased to 42% when length changes from 15 mm to 25 mm and there is about 35% increase in strength for length varies from 20 mm to 25 mm. In case of dissimilar joints, firstly there is about 16% increase in strength then there is 5% decrease while after that there is 45% increase in strength. Adhesion failure, cohesion failure and mixed failure were obtained experimentally during failure mode analysis. As the strength of joint increases, failure mode shows a transition from adhesion failure to cohesion failure. From the literature survey it is evident that limited work has been carried out on analysis of shear-tensile strength of adhesively bonded steel and aluminium joint with variation in bonding parameters. Not much work on failure mode analysis of bonded joints during tensile testing has been reported. In present work a noval attempt has been made to analyze the shear-tensile strength and failure mode of adhesively bonded steel and aluminium joint with variation in bonding parameters.

scholarly journals Experimental Study on Steel to FRP Bonded Lap Joints in Marine Applications

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Çiçek Özes ◽  
Nurhan Neşer
Keyword(s):  
Surface Roughness ◽  
Adhesive Bonding ◽  
Weight Ratio ◽  
Steel Structures ◽  
High Strength ◽  
Lap Joints ◽  
Bonded Joints ◽  
Bonding Performance ◽  
Marine Industry ◽  
Marine Applications

Steel structures coated with fiber-reinforced polymer (FRP) composites have gained wide acceptance in marine industry due to their high strength-to-weight ratio, good protection from environmental degradation, and impact loads. In this study, adhesive bonding performance of single-lap bonded joints composed of steel coated with FRP has been investigated experimentally for three different surface roughness and two epoxy types. Single-lap bonded joints have been tested under tensile loading. The adhesive bonding performance has been evaluated by calculating the strain energy values. The results reveal that the surface roughness of steel has a significant effect on the bonding performance of steel to FRP combinations and the performance of the resin can be improved by using the primer in an economical way.

Damage investigation on the adhesively bonded single-lap joints of three-dimensional braided composite and laminates

2017 ◽  
Vol 36 (10) ◽  
pp. 725-738 ◽  
Author(s):  
Xiao-Kang Li ◽  
Zhen-Guo Liu ◽  
YuChen Wei ◽  
Xiang Huang ◽  
Bing Lei
Keyword(s):  
Composite Structures ◽  
High Performance ◽  
Adhesive Bonding ◽  
Failure Process ◽  
Three Dimensional ◽  
Lap Joints ◽  
Tensile Failure ◽  
Failure Behavior ◽  
Braided Composite ◽  
Single Lap Joints

Adhesive bonding is usually used to fabricate composite structures that are hard to manufacture in one piece, however, their lightweight advantage is usually impaired by low failure strength. For high performance composite structures, bonding properties of joints dominate the failure performance and commonly are the primary target of structural optimization. Both experimental and numerical studies of failure behavior of single-lap joints with three-dimensional braided composite laminate adherends are presented in this paper. First, tensile failure tests were performed on braid-laminates single-lap joints bonded with epoxy resin. Compared with the laminates–laminates single-lap joints, the failure load of the braid–laminates single-lap joints increased by 18.4%. Then, the Finite Element Method (FEM) coupled with cohesive zone models (CZM), considering different value of overlap length (L), was used to perform the detail stress distribution of the overlap sections of SLJs. Further, damage initialization and crack growth of single-lap joints are analyzed in detail to fully characterize the failure process, and both experimental and numerical results lead to the same conclusion. Lastly, the effect of three-dimensional braided adherends’ braiding angle on braid-laminates single-lap joints’ performance was investigated, which provides suggestions for the design and optimization for adhesive bonded composite structures.

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