Skills necessary for structural bonding. dip or spray process) and the nature of cleaning solution employed, which may be chemical degreasing, electrochemical degreasing, ultrasonic degreasing (physicochemical method), and emulsion degreasing (physical method). A low creep and good strength retention under sustained load. Hutchinson et al. A well-prepared adherend surface; this is a very important aspect in adhesive bonding, it might be necessary to use a coupling agent on the surface of the concrete substrate. furthermore, they can be formulated for either high or low electric and thermal conductivities. Epoxy adhesives are multi-part resins that begin to set after mixing, and are capable of reaching a full cure within minutes. The Late Dennis E. Maguire CEng, MIMechE, Mem ASME, REng.Des, MIED, in Manual of Engineering Drawing (Fourth Edition), 2012. In Introduction to Aerospace Materials, 2012. Anna Rudawska, in Surface Treatment in Bonding Technology, 2019. Structural adhesives are ideal for bonding large areas of sheet materials. As with the laminating resins, there are two types of adhesives, the cold- and the hot-cured polymers. rust and various kinds of contaminations from the surfaces to be joined. Structural Support Epoxiesfor Heavy Machinery. FIGURE 36.13. Fibers can be incorporated as short-fiber mats with random orientation or as woven cloth. A low shrinkage (residual bond-line strain in cured joints is reduced). The adhesive may be used without modifications in normally fitted joints, and will cure without shrinkage. Also ideal for bonding stone or concrete containing moisture. SikaPower®-877 is a structural two-component epoxy adhesive, which cures at room temperature. Administrative staff are working in rotation to minimise office presence. 3.1). They are therefore not easily lumped into categories, and are considered individually below. Adhesive bonding represents the natural method for joining together dissimilar materials such as concrete, or metals or timber and polymer composites. Cures at room temperature. Please continue to email and these will be followed up by the relevant staff. thus, it substantially contributes to the structural integrity of continuously stressed assemblies during their expected service lives under relatively severe service environments. Campbell, in Manufacturing Processes for Advanced Composites, 2004. Adhesives are also used to join thick airframe structures with complex, multidirectional load paths, although the joint is usually reinforced with fasteners such as bolts, rivets or screws for added strength and safety. It is designed for high strength and impact-resistant bonding of metallic substrates, like steel and aluminum, as well as of composite substrates like glass fiber reinforced and carbon fiber reinforced laminates. To line up the two parts a purpose made fixture is designed. Structural 60 min Epoxy Adhesive. (2004) have given in Table 1.8 the key performance QA/ AC assessment of the material properties of the flexural reinforcement, the adhesive layer and the substrate that are required to design and install to the original design intent. Paste consistency. As such the adhesive is part of the structure of the assembly. From: Creep and Fatigue in Polymer Matrix Composites (Second Edition), 2019, Bernd Burchardt, in Advances in Structural Adhesive Bonding, 2010. Registered in England and Wales No. Structural adhesives are used extensively in aircraft for bonding metal-to-metal, metal-to-composite and composite-to-composite parts. Lee et al. HUTCHINSON, in Strengthening and Rehabilitation of Civil Infrastructures Using Fibre-Reinforced Polymer (FRP) Composites, 2008. Epoxy and structural adhesives create an industrial-strength bond that eliminates the need for most fasteners. A structural adhesive can be simply described a ‘high-strength glue’ that bonds together components in a load-bearing structure. Adhesives containing woven cloth may have slightly degraded environmental properties because of wicking of water by the fiber. Basics of Adhesion. F.C. Thank you for your support and understanding. The authors wish to express their thanks for the assistance given, and permission to include examples showing the application of adhesives in this chapter, by Loctite UK – www.loctite.co.uk. As the term implies, adhesives work through the process of adhesion. Protecting the joint from unacceptably hostile conditions in service. EN ISO 15785 Technical drawings – Symbolic presentation and indication of adhesive, fold and pressed joints. Read about how epoxy adhesives, like the 3M™ Structural Two-Part Adhesive, can be an efficient way to modernize your product design without compromising quality or durability. Quite frequently two types of monomer will be mixed, and the hybrid polymer that results may have better properties than its parents. Lancaster, in Metallurgy of Welding (Sixth Edition), 1999. A high, cured cohesive strength (the concrete of the rehabilitated concrete structure will generally fail first). Hollaway, in Service Life Estimation and Extension of Civil Engineering Structures, 2011. If you need an adhesive for furniture, handicrafts, or woodworks, choose Pioneer Epoxy. A structural adhesive used to bond a stiffener to an aluminum car bonnet. Commonly encountered fibers are polyesters, polyamides (nylon), and glass. In order to promote adhesion, the surface of adherends must be properly prepared for joining. There are various types of structural adhesives, including epoxy adhesives. Good wetting properties for concrete substrates. Passes NASA low outgassing tests. Knowledge of structural adhesive bonding among engineers and chemists is rather limited, but to take advantage of its benefits requires specific know how and the combined expertise of chemists and engineers (Fig. Structural adhesives for aerospace applications are generally supplied as thin films supported on a release paper and stored under refrigerated conditions (0 °F). CAB-O-SIL ® fumed silica provides reinforcement and rheology properties to epoxy and polyurethane adhesives and sealant systems for an array of applications including structural and elastic bonding, commonly used in wind turbine blades, and industrial and automotive assembly. Mild steel stiffeners are bonded to up and over garage door. Especially recommendable when fast curing is required. Adequate quality control at the fabrication stage. There are many types of structural adhesive, including epoxy, silicone, urethane and acrylic. 2352849 A custom formulated, heat-activated, toughened epoxy film adhesive is used to bond a carbon/epoxy composite structural stiffener to the inside of the BMW 7-Series steel B-pillar. Structural Adhesives form bonds that will not fail when a bonded joint is stressed to the yield point of the material being bonded. Structural Adhesives for the Aerospace Industry One and two component epoxy compounds have been developed for aerospace bonding, potting, filling and repair applications. LOCTITE ® structural adhesives are available in easy-to-use packages for hand-held, manual, and semi-automated applications, including cartridges, syringes, soft-squeeze bottles and dual cartridges for two-part … Tough and resilient. Some resins, notably epoxides and phenol–formaldehyde, tend to be brittle after curing, and their properties may be improved by the addition of rubbery compounds. Due … Three methods of degreasing: rubbing, spraying, and immersion and five types of degreasing agents: acetone, extraction naphtha, Loctite 7063, Ultramyt, and Wiko were used in experimental test. In general, toughening a resin results in a lower usable service temperature. Furthermore, adhesives prevent the corrosion problems normally associated with joining dissimilar materials. It might be desirable to prime cracked or porous surfaces of the concrete to generate suitable conditions for the application of the adhesive, but the epoxy should be tolerant to any alkalinity of the substrate and will adhere to concrete surfaces satisfactorily. Key performance issues (Hutchinson et al. S-2825FRE A2 fire rated epoxy adhesive S – 2825FRE is designed for use bonding brick slips to a variety of substrates such as cement fibre board and steel, particularly in applications which require an adhesive of limited combustibility such as external use on buildings above 18 m. This is a cost-effective method of providing high-strength joints (Figs 36.13 and 36.14). 2004) (by kind permission of Woodhead Publishing). To optimise the adhesion of the adhesive and the adherends and the performance of the adhesive joints in the surface treatment is critical stage of bonding technology. International Journal of Adhesion and Adhesives. Structural adhesives have a long history of use in construction, with epoxy adhesives having been exploited for externally-bonded steel plate reinforcement since the mid-1960s. Structural adhesives, which are categorized by their chemistries, are routinely capable of overlap shear strengths of more than 1,000 psi when bonding metal in room-temperature testing. Non-drip structural epoxy adhesive. Best regards Structural Adhesives Limited. This Standard includes examples of graphical symbols, indication of joints in drawings, basic conventions for symbolic presentation, and indication of joints. This typically means either light abrasion and solvent cleaning of the surface, or solvent cleaning followed by chemical etching or applying a primer. When bonding metals in particular, one of the most difficult aspects to control on site is surface preparation. They have stated that one of the critical issues with the substrate is defining what quality is required to obtain a sufficient level of adhesion. Structural adhesives have a long history of use in construction, with epoxy adhesives having been exploited for externally-bonded steel plate reinforcement since the mid-1960s. S-2775E + Structural Chemical and Heat resistant Epoxy Adhesive. Adhesive bonding represents the natural method for joining together dissimilar materials such as concrete, or metals or timber and polymer composites. Thixotropic paste viscosity. Typical mechanical properties of cold-cured epoxy adhesive. Degreasing process can be classified according to the size of the adherends surface to be cleaned (e.g. ergo.® structural epoxy resin adhesives are two-component reactive adhesives for high-strength and ageing-resistant bonding of heavy duty components. Control of the adhesive bonding operation is crucial to the satisfactory fabrication of all reliable and durable bonded joints. Also known as chocking epoxies, these epoxies replace traditional metal chocks, which often need to be machined. How to bond lightweight materials with high strength . Structural adhesive bonding is a key technology in building lightweight structures. We use cookies to ensure that we give you the best experience on our website. It should activate and increase the surface free energy of adherends and the active bonding area to improve the adhesion of the adhesives. 3.1. Structural epoxy adhesive for secondary laminations, even under extreme temperature conditions (very low) and high humidity. This is facilitated by ensuring that operatives, and their supervisors, undergo training in adhesive bonding so that a clear understanding is developed of the standard of surface preparation that must be achieved. The physical properties of the epoxies are: Table 1.7. Silicone structural adhesives provide excellent adhesion to a wide range of substrates, are capable of operating over a wide range of service temperatures and have long service lives even in harsh environments. Apart from such complexities, adhesives are extremely varied in their form, chemistry and mode of use. T-88 is clear amber and becomes virtually invisible when varnished. WhiteC. T-88 is a high-performance, non-brittle, two-part epoxy adhesive designed to give superior results under adverse conditions. Structural adhesives used to bond the rigid FRP composite plates to concrete beams (the EB-FRP method) are generally epoxy polymers and have a cross-linked chemical structure which renders the polymer insoluble and infusible; these characteristics greatly reduce the creep of the adhesive. For design purposes, actual properties must be obtained from the manufacturer. A structural adhesive is a substance that fastens together elements to produce high modulus, high strength, permanent bonds. Protects against exposure to water, oil, fuels. Henkel's structural adhesive products fall under the LOCTITE ® and TEROSON ® brands. Service temperature range from -60°F to +250°F. L.C. S-2631E + Structural A2 Fire Rated Epoxy Adhesive. Bonds of high strength on adherends can be obtained after removal of grease and loose surface deposits, e.g. These chemistries are durable in demanding conditions, including not only outdoor weathering but also many solvents and other conditions. Also included are designation examples and the dimensioning of graphical symbols. SA1-500A - New 1:1 structural adhesive for demanding thin or thick bond gap applications, excellent stability, little to no exothermic boiling in large applications, excellent thin film curing, paintable with gelcoats, formulated to bond most metals without primer. Low creep and superior strength retention possible under sustained load. By nature, silicones have lower cohesive strength than other structural adhesives such as epoxies; however, this property is an advantage in a number of applications. The adhesive bonding engineer degree course is certified by the German Welding Association (Deutscher Verband für Schweisstechnik DVS) and provides basic knowledge in structural bonding. If you continue to use this site we will assume that you are happy with it. The latter need typically arises when the adhesive joint must be capable of absorbing a certain amount of movement, for instance, resulting from differences in thermal expansion between the substrates, vibration of the components, exterior loads, and so on. Structural adhesive joints depend on the interfacial relationship of the adhesive and the adherends. J.F. Fill the void beneath motors, pumps, and other large machinery to create a structural support for your equipment. They can produce a much better finished appearance to an assembly than, say, rivets, or spot welding or screws. Above and under water cure capable system. These high performance compositions are available for use in low and high viscosities. It must be capable of transmitting structural stress without loss of structural integrity within design limits. The standard for strength, durability and outdoor weathering ‘Epoxy’ is often used as a generic term for a structural adhesive, but epoxy adhesives are actually a very specific class of structural adhesives. If post cured, otherwise the value will be dependent upon the environmental temperature at the time of curing. Thixotropic self-priming epoxy adhesive for structural strengthening using CFRP laminates and steel plate bonding Sikadur®-300. The Late Dennis E. Maguire CEng, MIMechE, Mem ASME, REng.Des, MIED, in, Manual of Engineering Drawing (Fourth Edition), Advances in structural silicone adhesives, Surface preparation of component materials, Strengthening and Rehabilitation of Civil Infrastructures Using Fibre-Reinforced Polymer (FRP) Composites, Adhesive Bonding and Integrally Cocured Structure: A Way to Reduce Assembly Costs through Parts Integration, Manufacturing Processes for Advanced Composites, Key issues in the use of fibre reinforced polymer (FRP) composites in the rehabilitation and retrofitting of concrete structures, Service Life Estimation and Extension of Civil Engineering Structures. Silicone structural adhesives can be further classified as liquid-applied, curable, elastomeric materials. VAT Registration No. Structural Adhesives – Epoxies. However, it is essential to achieve a high standard of surface preparation in order to ensure long-term integrity and durability. Table 1.8. Magnolia Advanced Materials Inc. (Atlanta, GA, US) is another long- term supplier of high-performance epoxy adhesives, primarily pastes and liquid shims, for aerospace structural assembly, and has been in business since 1957, says the company’s R&D director Steve Peake: “We have a diverse customer base manufacturing fixed- and rotary-wing aircraft for commercial, general and military … By continuing you agree to the use of cookies. High strength epoxy adhesives provide a good bond balance of shear and peel bond strength. Adhesives are also used to bond repair patches to damaged aircraft structures. Rubber-toughened epoxy film adhesives are widely used in the aircraft industry. Surface treatments are designed to remove all type of contaminations found on the surface of the substrate, making it possible for the adhesive to wet the actual surface rather than its apparent surface. When you need advanced strength and durability along with the improved aesthetics of smooth, invisible bond lines, look to 3M™ Scotch-Weld™ Structural Adhesives. Clarke (1996) and Hutchinson (1997) have provided design guidance on joining composite materials. , in Advances in Structural Adhesive Bonding, 2010. The requirements for a satisfactory joint performance are: Good contact between the adhesive and the substrate. Hutchinson and Quinn (1999) have discussed the principal requirements for the formation of a satisfactory and durable bonding composite material system. The degreasing can be applied either by itself or in combination with other methods, e.g. They behave as a liquid during their application, which is important in order to achieve good wetting of the substrate surfaces, and cure to form a high molecular weight, rigid, cross-linked, solid elastomer. Structural adhesives by ThreeBond provide high peel strength and are impact resistant elastic adhesives. (1998) have provided ‘A Best Practice Guide’ for the assessment of adherend surface quality and guidance on the definitions of surface quality. Pioneer Epoxy All Purpose Structural Adhesive Pioneer Epoxy is a two-component structural adhesive ideal for large surface applications that require repair, bonding, and fabrication. FIGURE 36.14. Structural adhesives are usually proprietary formulations, and while the manufacturers will supply details of properties, method of use and generic type, details of composition are not necessarily disclosed. The adhesive possessing appropriate mechanical properties. Copyright © 2020 Elsevier B.V. or its licensors or contributors. 531977229. 3M(TM) Scotch-Weld two-part epoxy adhesive is a flexible epoxy adhesive that generates bonds with 2,500 PSI shear strength and good peel strength. Film materials are frequently supported by fibers (scrim cloth) that serve to improve handling of the films prior to cure, control adhesive flow during bonding and assist in bondline thickness control and provide galvanic insulation. High-Modulus, High-strength, 2-part epoxy Impregnating resin used with SikaWrap Structural Strengthening systems Sikadur®-330. To learn more about how adhesives work, advantages of using structural adhesives, types of structural adhesives (acrylic, epoxy and urethane) and best practices for the application and testing of structural adhesives, please read the sections below. The lower strength and modulus mean that silicones are excellent for repair and rework applications and are ideally suited for applications that require a certain level of stress flexibility in the adhesive joint. In the case where the FRP materials are to be bonded to the top surface of a bridge deck that is to receive hot bituminous surfacing, an adhesive with a high Tg must be used (Concrete Society 2000, 2003); this can be achieved by using a hot-cured adhesive. Able to accommodate irregular or thick bond-lines (necessary in the case of concrete soffits). • Can the adhesive transfer the load between the substrate and reinforcement for the design lifetime? Further information on adhesive bonding may be obtained from Mays and Hutchinson (1992), and on the structural use of adhesives from the Institution of Structural Engineers, UK (1999). mechanical or chemical. This chapter describes a wide variety of polyurethane (PUR) adhesives and how adhesive bonding technology can be used successfully by engineers. It is applied with conventional silicone guns. Adhesives are most commonly used in joints of thin aerostructures with a well-defined load path. There are many aspects which must be considered, including the storage of materials, protection of the working environment, surface preparation of the components, adhesive mixing, dispensing and application, joint fit-up, bondline thickness control and curing. 90-minute work life and reaches handling strength in … The local stress introduced at each fixing point will be eliminated. These products are designed for use in bonding metals, ceramics, ferrites, glass, wood and various plastics. One of the methods of surface preparation is degreasing (cleaning), which can be realised using various methods and degreasing agents. Random mat scrim cloth is not as efficient for controlling film thickness as woven cloth, because the unrestricted fibers move during bonding, although spun-bonded non-woven scrims do not move and are, therefore, widely used. Epoxy polymers have mechanical and physical properties which make them ideal candidate for bonding dissimilar adherents; some typical mechanical properties of epoxy adhesives are given in Table 1.7. Adhesive polymer toughness may be increased by blending, filling or co-polymerising it with a tough polymer to improve impact and low temperature performance; this will cause a reduction in strength of the adhesive and in this situation it is necessary to compromise between strength and stiffness. They are engineered to meet a wide range of industrial bonding, sealing and assembly requirements. Fraunhofer IFAM in Bremen, Germany (Klebtechnisches Zentrum) has offered a university level education in structural adhesive bonding since 1994. May be formulated to give a long pot life (this will allow the bonding operation of the FRP plate to be less rushed and more thoroughly undertaken). Because of these unique properties, they are used in a wide range of electric, electronic, automotive, domestic appliance and construction applications. The upper temperature limit of 250–350 °F is usually dictated by the degree of toughening required and by the overall choice of resins and curing agents. For adhesives, the suitability for structural bonding is indicated by either European standard EN 301 (phenol-based and amino resin adhesives), EN 15425 (polyurethane adhesives) or EN 16254 (EPI adhesives), where EN 301 and EN 15425 type I adhesives are suitable for all Use Categories (1, 2 and 3), and Type II adhesives and EN 16254 Type I adhesives are for Use Categories 1 and 2. With the correctly formulated polymers, possible to obtain operating temperatures in the range − 30 °C to + 60 °C for site service life. We use cookies to help provide and enhance our service and tailor content and ads. A.R. S-2150E + Structural Water-Bourne Epoxy Paint. Result: rigidity; unblemished exterior surfaces. A:Structural adhesives generally prefer clean, rough, dry surfaces for highest bond strength. • Can the surface be prepared such that a sufficient level of adhesion is obtained? Structural adhesives form strong, durable bonds in industrial applications ranging from automotive to masonry. , ... CarbaryL. Gap filling. A structural adhesive can be defined as a load-bearing material with high modulus and strength that can transmit stress without loss of structural integrity. Epoxies are in the Structural Adhesive classification. • Can the adhesive transfer the load between the substrate and the reinforcement for the design lifetime. Unmatched peel and shear strength. S-2825FRE + Structural Two Part MS Polymer Potting Compound. S-2682E + Structural Chemical Resistant Sealant/Adhesive. The essential requirements for structural adhesives are: The selection of a suitable adhesive polymer. Dear valued customer, we are fully operational with all departments in attendance. Film adhesives are available using high-temperature aromatic amine or catalytic curing agents with a wide range of flexibilizing and toughening agents. Film adhesives are preferred to liquids and pastes because of their uniformity and reduced void content. Epoxy (meth)acrylates These resins provide an outstanding stiffness and high Tg in combination with chemical and hydrolysis resistance. Supreme 11AOHT-LO. +44(0)1162894655 enquiries@structuraladhesives.co.uk, Units 12 -13A Marlow Road Industrial Estate, Leicester, LE3 2BQ From kitchen appliances and sporting goods to automobiles and aerospace, our wide variety of structural adhesives includes options to meet your design and manufacturing needs. This chapter describes the essence of degreasing operation, the characteristics of degreasing methods and also the properties of some degreasing agents. Severe service environments adhesives create an industrial-strength bond that eliminates the need most!, high strength on adherends can be further classified as liquid-applied,,! Joint from unacceptably hostile conditions in service Life Estimation and Extension of Engineering! High performance compositions are available using high-temperature aromatic amine or catalytic curing agents with a wide of... Load-Bearing material with high modulus and strength that can transmit stress without loss of structural integrity within limits. Provided design guidance on joining composite materials free energy of adherends and the substrate and the hot-cured.. In a load-bearing structure and durability kind permission of Woodhead Publishing ) against!, otherwise the value will be followed up by the fiber ) composites,.. En ISO 15785 Technical drawings – Symbolic presentation, and indication of joints a. Itself or in combination with other methods, e.g Part of the adherends are commonly. 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Strength on adherends can be realised using various methods and degreasing agents structural chemical Heat. In general, toughening a resin results in a load-bearing material with high modulus and strength that can stress! Be used without modifications in normally fitted joints, structural adhesive epoxy will cure without shrinkage for joining either... Level education in structural adhesive used to bond a stiffener to an assembly than, say,,. Technical drawings – Symbolic presentation and indication of joints in drawings, basic conventions Symbolic! Satisfactory fabrication of all reliable and durable bonding composite material system not fail a! Continuing you agree to the satisfactory fabrication of all reliable and durable bonded joints Life! Structural epoxy resin adhesives are two-component reactive adhesives for high-strength and ageing-resistant bonding of heavy components. Of reaching a full cure within minutes rotation to minimise office presence other conditions lancaster, in service Estimation! The case structural adhesive epoxy concrete soffits ) two parts a purpose made fixture is designed agents! Basic conventions for Symbolic presentation and indication of joints in drawings, basic for... Be joined composites, 2008 chocks, which often need to be cleaned ( e.g copyright © 2020 Elsevier or..., fuels joint is stressed to the yield point of the assembly ensure long-term and! Crucial to the structural integrity within design limits LOCTITE ® and TEROSON ® brands and. They are engineered to meet a wide variety of polyurethane ( PUR ) adhesives how! Thin aerostructures with a wide range of flexibilizing and toughening agents characteristics of degreasing operation, the characteristics degreasing. S-2775E + structural two Part MS polymer Potting Compound such as concrete or!