The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform
L. F.m. Da Silva - One of the best experts on this subject based on the ideXlab platform.
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Static strength prediction of Adhesive Joints: A review
International Journal of Adhesion and Adhesives, 2020Co-Authors: L.d.c. Ramalho, R.d.s.g. Campilho, Jorge Belinha, L. F.m. Da SilvaAbstract:Abstract The use of Adhesive Joints has gathered increasing interest in recent years due to their advantages over conventional bonding techniques, namely lighter structures and decreased stress concentrations. Consequentially, the strength prediction of Adhesive Joints has been studied extensively. This review aims to describe and compare the most relevant methods for the strength prediction of Adhesive Joints. These methods can be divided into analytical and numerical methods. Analytical methods are generally limited to initial design evaluations or to simple Joints. Numerical methods are more commonly used, especially when joint design is complex. Between the different numerical methods, Cohesive Zone Models (CZM) are the most popular method to predict the strength of Adhesive Joints. This approach is able to predict the strength of a wide range of joint designs with minimal errors. However, it requires the determination of cohesive laws that generally change depending on different geometrical parameters of the Joints. Advanced numerical techniques, such as the eXtended Finite Element Method (XFEM) or Meshless Methods have been used to study Adhesive Joints, but their application needs improvements before they can be more extensively used.
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environmental effect on the fatigue degradation of Adhesive Joints a review
Journal of Adhesion, 2017Co-Authors: M Costa, L. F.m. Da Silva, G. Viana, R.d.s.g. CampilhoAbstract:ABSTRACTEnvironmental factors, such as temperature and moisture, are known to have a degrading effect on the mechanical properties and performance of Adhesive Joints, which may be perceived as a non-problem because various works have shown that the static response of an Adhesive is normally unaffected by slight moisture and temperature variations that occur in real-world applications. While this may be true, performance under purely static conditions is rarely found in commercial uses and most Adhesive Joints are subjected to cyclic loadings throughout their life. Interestingly, not much work has been done on the effects of the environment on cyclically loaded Adhesive Joints, but the consensus is that the fatigue response is much more affected by environmental changes than the static response, which is arguably the most important analysis. The general trend is that hygrothermal ageing decreases the number of cycles the joint can withstand and also decreases the threshold fracture toughness value, which t...
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Dynamic behaviour of composite Adhesive Joints for the automotive industry
Composite Structures, 2017Co-Authors: H.a.m. Araújo, J.j.m. Machado, E.a.s. Marques, L. F.m. Da SilvaAbstract:The automotive industry has significantly increased the use of Adhesive Joints in vehicle construction, which can be explained in part by the widespread adoption of composite materials and structures. The combined use of composites and bonding allows the manufacture of structures with high mechanical strength and reduced weight. However, to ensure vehicle safety, these Adhesive Joints must be able to sustain large impact loads, transmitting the load to the structure without damaging the joint. This work aims to study the impact behaviour of composite Adhesive Joints bonded with a ductile epoxy Adhesive, comparing different overlap lengths. For this purpose, a characterization of the behaviour of single lap Joints was performed under quasi-static and impact conditions. Dynamic tests were also performed using vibration analysis to assess the damping capabilities of the studied Joints. Numerical models were developed with cohesive elements in ABAQUS® software, including both quasi-static and dynamic models. It was demonstrated that Joints manufactured with this type of Adhesives and substrates can exhibit excellent impact strength and damping capabilities. It was also shown that the behaviour of these Joints can be successfully modelled using static and dynamic finite element analysis.
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A review on the temperature and moisture degradation of Adhesive Joints
Proceedings of the Institution of Mechanical Engineers Part L: Journal of Materials: Design and Applications, 2016Co-Authors: G. Viana, Banea, M Costa, L. F.m. Da SilvaAbstract:Despite offering very attractive advantages over traditional joining methods, one of the setbacks of Adhesive bonding is its long-term strength in aggressive environments, such as environments with high moisture and extreme temperatures. With the rise of new lightweight materials and their recent use in everyday vehicles, transportation industries have been very interested in determining the long-term behavior of Adhesive Joints. The aim is to build durable, lighter vehicles, which consume less energy and emit less pollution. The two main factors that affect the strength of vehicle Adhesive Joints are exposure to moist environments and high and low temperatures. There are some works concerning the effect of these two factors separately and some predictive models have been developed, which help the engineer to design reliable, safe, and efficient Adhesive Joints. However, the combined effect of temperature and moisture is not yet totally understood. This paper presents a review on the temperature and moist...
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parametric study of Adhesive Joints with composites
International Journal of Adhesion and Adhesives, 2012Co-Authors: J A B P Neto, R.d.s.g. Campilho, L. F.m. Da SilvaAbstract:Abstract Adhesively-bonded Joints are increasingly used in aeronautical industry. Adhesive Joints permit to join complex shapes and reduce the weight of structures. The need to reduce the weight of airplanes is also increasing the use of composites. Composites are very anisotropic: in the fibre directions, unidirectional composites can be very strong and stiff, whereas the transverse and shear properties are much lower. Bonded Joints experience peel loading, so the composite may fail in transverse tension before the Adhesive fails. That is why it is important to study these Joints and try to find reliable ways to predict the strength of Joints with composite adherends. The main goal of this study was to understand the failure in Adhesive Joints with composites, bonded with Adhesives with different characteristics, and find reliable ways to predict them. Experimental tests were carried with single lap Joints with composite adherends and different Adhesives, brittle and ductile, with several overlap lengths. A Cohesive Zone Model (CZM) was taken into consideration to predict the results observed during the experimental tests. The experimental results were also compared with simple analytical models and the suitability of each model was evaluated for each bonded system.
E.a.s. Marques - One of the best experts on this subject based on the ideXlab platform.
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Adhesives and Adhesive Joints under impact loadings an overview
Journal of Adhesion, 2018Co-Authors: J.j.m. Machado, E.a.s. Marques, Lucas F M Da SilvaAbstract:ABSTRACTThe study of the behaviour of Adhesive Joints under impact loadings is a very active field of research, driven by significant industrial interest. Many industries, such as the automotive industry, are currently employing Adhesive Joints extensively, making use of the inherent properties of Adhesive Joints to improve the mechanical behaviour, reduce weight, and simplify manufacturing. Reduced structural weight is achieved by combining multiple lightweight materials, which is made possible by using Adhesive Joints. Impact strength is also a major factor, as vehicles must be able to provide adequate safety levels for their occupants during collisions. Another example of industrial application is the defence industry, which uses bonded structures to withstand ballistic impacts, with extremely high impact velocities. Understanding the behaviour of Adhesive Joints under impact is, therefore, crucial for designing stronger and safer structures. This document aims to review the research that has been prev...
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Dynamic behaviour of composite Adhesive Joints for the automotive industry
Composite Structures, 2017Co-Authors: H.a.m. Araújo, J.j.m. Machado, E.a.s. Marques, L. F.m. Da SilvaAbstract:The automotive industry has significantly increased the use of Adhesive Joints in vehicle construction, which can be explained in part by the widespread adoption of composite materials and structures. The combined use of composites and bonding allows the manufacture of structures with high mechanical strength and reduced weight. However, to ensure vehicle safety, these Adhesive Joints must be able to sustain large impact loads, transmitting the load to the structure without damaging the joint. This work aims to study the impact behaviour of composite Adhesive Joints bonded with a ductile epoxy Adhesive, comparing different overlap lengths. For this purpose, a characterization of the behaviour of single lap Joints was performed under quasi-static and impact conditions. Dynamic tests were also performed using vibration analysis to assess the damping capabilities of the studied Joints. Numerical models were developed with cohesive elements in ABAQUS® software, including both quasi-static and dynamic models. It was demonstrated that Joints manufactured with this type of Adhesives and substrates can exhibit excellent impact strength and damping capabilities. It was also shown that the behaviour of these Joints can be successfully modelled using static and dynamic finite element analysis.
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Behaviour under Impact of Mixed Adhesive Joints for the Automotive Industry
Latin American Journal of Solids and Structures, 2016Co-Authors: M. R. G. Silva, E.a.s. Marques, Lucas F M Da SilvaAbstract:The automotive industry is increasingly using Adhesive Joints bonding advanced lightweight materials to reduce vehicle weight. Strength under impact loadings is a major concern for this application and mixed Adhesive Joints can effectively improve the Joints by combining stiffness and flexibility on the same overlap. This work introduces and studies several configurations for static and impact tests of mixed Adhesive Joints with four Adhesives in different combinations. The main purpose of this work is the development of a strong Adhesive joint using a mixed Adhesive layer and perform a series of mechanical to study its mechanical behaviour. It is concluded that the use of the mixed Adhesive technique improves both static and impact strength by introducing flexibility to the joint which subsequently allows more energy absorption when introduced in crash resistant structures.
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testing and simulation of mixed Adhesive Joints for aerospace applications
Composites Part B-engineering, 2015Co-Authors: E.a.s. Marques, Lucas F M Da Silva, M FlavianiAbstract:Abstract An important aerospace application of Adhesives is in heat shields, bonded with room temperature vulcanizing silicone Adhesive, which has high temperature resistance but low strength. Previous works proposed mixed Adhesive Joints as a solution and an investigation of this technique was performed. Three Adhesive joint configurations were tested, including a mixed joint. The aim of the research was to simulate the load on a heat shield and predict the joint strength. Ceramic properties were obtained with an inverse method. There was a good agreement between experimental and numerical data, showing that this technique could be used for prediction and optimization.
Lucas F M Da Silva - One of the best experts on this subject based on the ideXlab platform.
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Adhesives and Adhesive Joints under impact loadings an overview
Journal of Adhesion, 2018Co-Authors: J.j.m. Machado, E.a.s. Marques, Lucas F M Da SilvaAbstract:ABSTRACTThe study of the behaviour of Adhesive Joints under impact loadings is a very active field of research, driven by significant industrial interest. Many industries, such as the automotive industry, are currently employing Adhesive Joints extensively, making use of the inherent properties of Adhesive Joints to improve the mechanical behaviour, reduce weight, and simplify manufacturing. Reduced structural weight is achieved by combining multiple lightweight materials, which is made possible by using Adhesive Joints. Impact strength is also a major factor, as vehicles must be able to provide adequate safety levels for their occupants during collisions. Another example of industrial application is the defence industry, which uses bonded structures to withstand ballistic impacts, with extremely high impact velocities. Understanding the behaviour of Adhesive Joints under impact is, therefore, crucial for designing stronger and safer structures. This document aims to review the research that has been prev...
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effect of material on the mechanical behaviour of Adhesive Joints for the automotive industry
Journal of Adhesion Science and Technology, 2017Co-Authors: M D Banea, Lucas F M Da Silva, Ricardo J C Carbas, R.d.s.g. CampilhoAbstract:AbstractOne parameter that influences Adhesively bonded Joints performance is the adherend material and its effect should be taken into consideration in the design of Adhesive Joints. In this work, the effect of material on the mechanical behaviour of Adhesive Joints was investigated experimentally and numerically by single lap Joints (SLJs) with different adherend materials (high strength steel, low strength steel and composite). The Adhesives selected were two new modern tough structural Adhesives used in the automotive industry. It was found that, for relatively short overlaps in SLJs bonded with structural modern tough Adhesives, failure is dominated by Adhesive global yielding and the influence of material on joint strength is not significant. For larger overlaps, the failure is not anymore due to global yielding and the effect of material becomes more important. Moreover, it was possible to evaluate which Adhesive is more suited for each material.
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Water Diffusion in Double Cantilever Beam Adhesive Joints
Latin American Journal of Solids and Structures, 2017Co-Authors: G. Viana, Marcelo Costa, Mariana D. Banea, Lucas F M Da SilvaAbstract:STRUCTURAL AdhesiveS ARE INCREASINGLY BEING USED IN THE AEROSPACE AND AUTOMOTIVE INDUSTRIES. THEY ALLOW FOR LIGHT WEIGHT VEHICLES, FUEL SAVINGS AND REDUCED EMISSIONS. HOWEVER, THE ENVIRONMENTAL DEG-RADATION OF Adhesive Joints IS A MAJOR SETBACK IN ITS WIDE IMPLEMEN-TATION. MOISTURE DEGRADATION OF Adhesive Joints INCLUDES PLASTICIZA-TION, ATTACKING OF THE INTERFACE, SWELLING OF THE Adhesive AND CONSE-QUENT CREATION OF RESIDUAL STRESSES. THIS MAY LEAD TO REVERSIBLE AND IRREVERSIBLE DAMAGE. IN THIS WORK DOUBLE CANTILEVER BEAM (DCB) SPECIMENS USING TWO DIFFERENT AdhesiveS FOR THE AUTOMOTIVE INDUSTRY WERE SUBJECTED TO TWO DIFFERENT AGEING ENVIRONMENTS. THEY WERE TESTED PERIODICALLY UNTIL THE TOUGHNESS OF THE AdhesiveS STABILIZED, WHICH MEANS THAT THEY WERE FULLY DEGRADED. AN ASSOCIATION WAS MADE BETWEEN THE TOUGHNESS OF THE Adhesive AND THE AMOUNT OF WATER THAT IT HAD ABSORBED. THIS WAY IT WAS POSSIBLE TO INDIRECTLY MEASURE THE WATER UPTAKE IN AN Adhesive JOINT TAKING INTO ACCOUNT THE WATER UPTAKE PROPERTIES OF THE AdhesiveS STUDIED, WHICH HAD BEEN DETERMINED IN ANOTHER STUDY. IT WAS FOUND THAT DIFFUSION OF WATER INTO THE STUDIED Adhesive Joints WAS FASTER THAN DIFFUSION THROUGH THE BULK Adhesive ALONE. A MODEL THAT TAKES INTO ACCOUNT DIFFUSION THROUGH THE INTERFACE BETWEEN THE Adhesive AND THE ADHERENDS WAS PROPOSED.
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Behaviour under Impact of Mixed Adhesive Joints for the Automotive Industry
Latin American Journal of Solids and Structures, 2016Co-Authors: M. R. G. Silva, E.a.s. Marques, Lucas F M Da SilvaAbstract:The automotive industry is increasingly using Adhesive Joints bonding advanced lightweight materials to reduce vehicle weight. Strength under impact loadings is a major concern for this application and mixed Adhesive Joints can effectively improve the Joints by combining stiffness and flexibility on the same overlap. This work introduces and studies several configurations for static and impact tests of mixed Adhesive Joints with four Adhesives in different combinations. The main purpose of this work is the development of a strong Adhesive joint using a mixed Adhesive layer and perform a series of mechanical to study its mechanical behaviour. It is concluded that the use of the mixed Adhesive technique improves both static and impact strength by introducing flexibility to the joint which subsequently allows more energy absorption when introduced in crash resistant structures.
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testing and simulation of mixed Adhesive Joints for aerospace applications
Composites Part B-engineering, 2015Co-Authors: E.a.s. Marques, Lucas F M Da Silva, M FlavianiAbstract:Abstract An important aerospace application of Adhesives is in heat shields, bonded with room temperature vulcanizing silicone Adhesive, which has high temperature resistance but low strength. Previous works proposed mixed Adhesive Joints as a solution and an investigation of this technique was performed. Three Adhesive joint configurations were tested, including a mixed joint. The aim of the research was to simulate the load on a heat shield and predict the joint strength. Ceramic properties were obtained with an inverse method. There was a good agreement between experimental and numerical data, showing that this technique could be used for prediction and optimization.
Venkitanarayanan Parameswaran - One of the best experts on this subject based on the ideXlab platform.
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dynamic shear strength of Adhesive Joints made of metallic and composite adherents
Materials & Design, 2010Co-Authors: Sohan Lal Raykhere, Prashant Kumar, Ramadhar Singh, Venkitanarayanan ParameswaranAbstract:Abstract The use of Adhesive Joints has gained good acceptance in the automotive and aerospace industries in recent years, particularly for joining glass fiber reinforced plastics (GFRP) to metals. Such Joints will be subjected to short duration dynamic loads in service. The present study focuses on the evaluation of the shear strength of Adhesive Joints prepared using four different commercial Adhesives at loading rates in the range of 0.6–1.2 MPa/μs. The Adhesives used were Araldite 2014, Araldite 2011, Epibond 1590 and A/B Loctite 324. Joints were prepared with two different adherent combinations; aluminum–aluminum and aluminum–GFRP. The results of the study indicated that, depending on the Adhesive and adherent combination, the dynamic strength was 2–4 times the static strength. Among the four Adhesives, Epibond 1590 exhibited the highest rate sensitivity whereas Loctite 324 exhibited the least. Further it was also observed that the dynamic strength was not sensitive to the adherent combination whenever the failure was predominantly within the Adhesive layer.
H.a.m. Araújo - One of the best experts on this subject based on the ideXlab platform.
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Dynamic behaviour of composite Adhesive Joints for the automotive industry
Composite Structures, 2017Co-Authors: H.a.m. Araújo, J.j.m. Machado, E.a.s. Marques, L. F.m. Da SilvaAbstract:The automotive industry has significantly increased the use of Adhesive Joints in vehicle construction, which can be explained in part by the widespread adoption of composite materials and structures. The combined use of composites and bonding allows the manufacture of structures with high mechanical strength and reduced weight. However, to ensure vehicle safety, these Adhesive Joints must be able to sustain large impact loads, transmitting the load to the structure without damaging the joint. This work aims to study the impact behaviour of composite Adhesive Joints bonded with a ductile epoxy Adhesive, comparing different overlap lengths. For this purpose, a characterization of the behaviour of single lap Joints was performed under quasi-static and impact conditions. Dynamic tests were also performed using vibration analysis to assess the damping capabilities of the studied Joints. Numerical models were developed with cohesive elements in ABAQUS® software, including both quasi-static and dynamic models. It was demonstrated that Joints manufactured with this type of Adhesives and substrates can exhibit excellent impact strength and damping capabilities. It was also shown that the behaviour of these Joints can be successfully modelled using static and dynamic finite element analysis.
