TALAT Lecture 4701: Terms and Definitions for Adhesive Bonding
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The document is a detailed lecture on adhesive bonding of metals, particularly aluminum, outlining key terms, definitions, and characteristics of adhesives, as well as their classification and properties. It covers the advantages and disadvantages of adhesive joining, the mechanisms behind adhesion and cohesion, and the physics of adhesive joints. It serves as a foundational guide for understanding adhesive bonding processes in conjunction with material science and engineering principles.
![Structure of Adhesives
Duromere Thermoplastic Thermoplastic
Cross-Linked String Molecules String Molecules
Molecules
Amorphous Amorphous Partly Crystalline
Construction of Polymer Structures of Monomeres
Source: Habenicht
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Structure of Adhesives 4701.02.05
Training in Aluminium Application Technologies
Properties of duromeres
Properties of Adhesive Layer
E
Modulus of Elasticity E
sB
B
e
Total Elongation
Tensile Strength
sB
Decomposition
Temperature Range
eB
Temperature [ T ]
Strength Parameters of Duromeres as a Function of Temperature
alu
Properties of Duromeres 4701.02.06
Training in Aluminium Application Technologies
With increasing temperature up the decomposition temperature, the tensile strength and
modulus of elasticity of the thermosetting plastics falls only slightly but the elongation
increases somewhat (Figure 4701.02.06).
Properties of amorphous thermoplastics
With increasing temperature, the tensile strength and modulus of elasticity of the
thermoplastics fall almost uniformly with the elongation increasing at the same time. On
TALAT 4701 14](https://image.slidesharecdn.com/talat-lecture-4701-terms-and-definitions-for-adhesive-bonding1520/85/TALAT-Lecture-4701-Terms-and-Definitions-for-Adhesive-Bonding-14-320.jpg)
![Creep properties of adhesive layers
The tendency of adhesives to creep is the main factor governing the time-temperature
behaviour of the adhesive joint. Creep can be defined as the time-dependent increase in
length of viscoelastic substances subject to a constant tensile load, whereby an
asymptotical load-dependent limiting value of elongation is reached.
Creep Properties of Adhesive Layer
3
Creep Strain [ V ]
2
1
Time [ t ]
Schematic Illustration of the Creep Strain of Adhesives
Source: Späth
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Creep Properties of Adhesive Layer 4701.02.10
Training in Aluminium Application Technologies
A typical creep curve exhibits 3 stages of creep (Figure 4701.02.10):
− Primary (transient) creep: - elastic deformation of molecules - rupture of secondary
valency bonds and rearrangement of linked-chain segments - no plastic deformation.
− Secondary (stationary) creep: - constant creep rate - equilibrium between the
competing processes of rupture and creation of new bonds within the molecule
aggregate.
− Tertiary (accelerated) creep: - rupture of adhesive joint initiated - deformation limit
of adhesive layer reached.
Variation of creep strength with temperature
The hardened adhesive layers of the best-known base substances (i.e., phenolic resins,
epoxy resins, epoxy nylons, polyurethane) exhibit a strength behaviour within large
regions of temperatutes similar to the one shown in Figure 4701.02.11.
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TALAT Lecture 4701: Terms and Definitions for Adhesive Bonding
- 1. TALAT Lecture 4701 Adhesive Bonding - Terms and Definitions 20 pages, 24 figures Basic Level prepared by Lutz Dorn, Technische Universität, Berlin Objectives: − to define the terms and definition of adhesive bonding of metals − to describe the basic physical/chemical characteristics of adhesive bonding − to describe the characteristics and the properties of adhesives used in metal bonding Prerequisites: − general background in production engineering and material science − background in the physics and chemistry of metallic surfaces and polymer science Date of Issue: 1994 EAA - European Aluminium Association
- 2. 4701 Terms and Definitions for Adhesive Bonding Table of Contents 4701 Terms and Definitions for Adhesive Bonding .......................................2 4701.01 Definition and Application of Adhesive Bonding .................................... 3 Adhesive bonding of aluminium..............................................................................3 Classification of adhesive bonding ..........................................................................3 Load distribution of joints........................................................................................4 Advantages and disadvantages of adhesive joining.................................................4 Structure of an adhesive joint ..................................................................................5 Adhesion and cohesion ............................................................................................6 Mechanism of deposition of macromolecules on surfaces ......................................7 Bond types in adhesive joints...................................................................................8 Bond forces in adhesive joints (dipole bonds).........................................................8 Bond forces in adhesive joints (hydrogen bonds) ....................................................9 Failure of adhesive joints .......................................................................................10 4701.02 Classification, Characteristics and Properties of Adhesives.............. 10 Classification of adhesives.....................................................................................10 Physically bonding adhesives ................................................................................11 Chemically reacting adhesives...............................................................................12 Classification of adhesives according to forming reaction and polymer structure 12 Structure of adhesives ............................................................................................13 Properties of duromeres .........................................................................................14 Properties of amorphous thermoplastics................................................................14 Properties of partly crystalline thermoplastics .......................................................15 Stress-strain curve of AlCuMg2 and an epoxy resin adhesive ...............................16 Creep properties of adhesive layers .......................................................................17 Variation of creep strength with temperature ........................................................17 Temperature stability of different adhesive basis ..................................................18 4701.03 Literature/References ............................................................................ 19 4701.04 List of Figures............................................................................................ 20 TALAT 4701 2
- 3. 4701.01 Definition and Application of Adhesive Bonding • Adhesive bonding of aluminium • Classification of adhesive bonding • Load distribution of joints • Advantages and disadvantages of adhesive joining • Structure of an adhesive joint • Adhesion and cohesion • Mechanism of deposition of macromolecules on surfaces • Bond types in adhesive joints • Bond forces in adhesive joints (dipole bonds) • Bond forces in adhesive joints (hydrogen bonds) • Failure of adhesive joints Adhesive bonding of aluminium Adhesive joining is defined as the process of joining parts using a non-metallic substance (adhesive) which undergoes a physical or chemical hardening reaction causing the parts to join together through surface adherence (adhesion) and internal strength (cohesion) (Figure 4701.01.01). Adhesive Bonding of Aluminium alu Adhesive Bonding of Aluminium 4701.01.01 Training in Aluminium Application Technologies Classification of adhesive bonding In the German standards DIN 8580 and 8593, adhesive joining is classified within the manufacturing processes in the main group joining, the group combination of substances and the subgroup adhesive joining, together with welding and brazing/soldering (Figure 4701.01.02). TALAT 4701 3
- 4. Classification of Adhesive Joining in the Manufacturing Process According to DIN 8580 and DIN 8593 Manufacturing Process Main Group Groups Subgroups 1. Amorphous Material 4.1 Combining 4.6.1 Welding Forming 4.2 Filling 4.6.2 Brazing/Soldering 2. Forming 4.3 Mechanical Joining 3. Separating 4.4 Joining by Processing Amorphous Materials Adhesive Joining 4.5 Joining by Forming Joining Process 4.6 Combining Materials 5. Coating 6. Altering Material Combining Materials Properties alu Classification of Adhesive Bonding 4701.01.02 Training in Aluminium Application Technologies Load distribution of joints The main advantage of adhesive joining over welding, riveting, brazing and screw fastening is that the load is distributed more evenly at right angles to the loading direction (Figure 4701.01.03). In the direction of the loading itself, however, this is valid only for scarfed adhesive joints. Load Distribution at Joints Welded Joints Riveted Joints Adhesive Joint alu Load Distribution at Joints 4701.01.03 Training in Aluminium Application Technologies Advantages and disadvantages of adhesive joining It must be remarked that all the different joining processes are not generally competitive and should rather be considered as being complementary. The appropriate joining technology for any application should be chosen on the basis of TALAT 4701 4
- 5. its technological and/or economical superiority. The list showing the advantages and disadvantages of adhesive joining serves as a help in choosing the appropriate joining method (Figure 4701.01.04). Advantages Disadvantages 1. Load distributed uniformly at right 1. Influence of time on process properties angles to loading direction 2. Pretreatment of joining parts surfaces 2. Microstructure unaffected 3. Limited form stability 3. Distortion-free joining 4. Different materials can be joined 4. Process parameters must be held 5. Very thin parts can be joined within very narrow range;low tolerance 6. Weight saving, light constructions 5. Change of properties of joint with time 7. Heat-sensitive materials can be joined (ageing of adhesive layer etc.) 8. Metals with different electrochemical properties can be joined (insulating 6. Complicated control of process effect of adhesive) 7. Low peeling strength, creep sensitive 9. High strength in combination with 8. Low adhesive layer strength must e riveting, spot welding screw- compensated by large joining area fastenings (eliminates crack corrosion) 10.High fatigue strength, good vibration 9. Repair possibilities limited damping 10.Complicated strength calculation Source: Habenicht alu Advantages and Disadvantages of Adhesive Joining 4701.01.04 Training in Aluminium Application Technologies Structure of an adhesive joint Adhesive joints are composite systems whose strength depends on both the geometrical design and loading type as well as on the schematically illustrated individual strengths of the components to be joint, the adhesive and the interface layer. As in every composite system consisting of different members, the overall strength is limited by the weakest member (Figure 4701.01.05). TALAT 4701 5
- 6. Structure of an Adhesive Joint 1 1 = Strenght of Material to Be Joint 2 2 = Adhering Strenght of the Metal Surface 3 Layer (Ex. Oxide Layer on Base Material) 4 3 = Strenght of the Metal Surface Layer 5 6 4 = Strenght of the Adhesion Bonding 5 4 Between Metal Surface Layer and 3 Adhesive Layer 2 5 = Strenght of Adhesive Layer Bordering 1 the Interface 6 = Cohesion Strenght of the Adhesive Layer alu Structure of an Adhesive Joint 4701.01.05 Training in Aluminium Application Technologies Adhesion and cohesion Adhesion is defined as the adhesive force acting between the adhesive and the surface of the material. This force is the result of the mechanical interlocking between adhesive and the material surface roughness (mechanical adhesion) as well as the physical and/or chemical interaction between the adhesive and the material (specific adhesion). Cohesion is the strength of the adhesive itself. This is a result of the mechanical entangling and interlocking of the adhesive molecules and their physical and/or chemical affinity for each other (Figure 4701.01.06). Adhesion Cohesion Specific Adhesion Mechanical Adhesion Cohesion Physical attractive True chemical Mechanical interlocking forces (adsorption) bonding between with microtopographic between atoms and atoms and molecules surface roughness molecules (chemisorption) Source: Fauner, Endlich alu Training in Aluminium Application Technologies Definitions of Adhesion and Cohesion 4701.01.06 TALAT 4701 6
- 7. A necessary condition for attaining high adhesion forces is the ability of the adhesive to wet the surfaces of the joining parts properly. The wetting is optimal when the angle of contact α does not exceed 30° (Figure 4701.01.07). This can be achieved, in principle, by a suitable surface treatment of the joining parts and by choosing an appropriate viscosity for the adhesive. Macromolecules, and consequently adhesives also, are adsorbed point-wise and as loops on the solid surfaces. adhesive wetting angle α substrate surface α=0° α<90° α=90° α>90° α=180° spreading good incomplete none wetting alu Correlation between Wetting Angle and Wetting Behaviour 4701.01.07 Training in Aluminium Application Technologies of Adhesives Mechanism of deposition of macromolecules on surfaces During hardening, the parts of the molecular chains which are not adsorbed, form the solid adhesive layer due to the formation of intermolecular forces (main and/or secondary valency forces (Figure 4701.01.08). Among the chemical bond types, the homopolar bonds (atomic bonds, non-polar bonds, covalent bonds) are the deciding factors for the manufacturing and wetting capacity of adhesives (formation of main valency bonds). The metallic bond is important for the formation of high adhesion forces through chemisorption. TALAT 4701 7
- 8. Mechanism of Deposition of Macromolecules on Surfaces Desposition Mechanism of Macromolecules on Surfaces Source: Jenkel, Rumbach alu Mechanism of Deposition of Macromolecules on Surfaces 4701.01.08 Training in Aluminium Application Technologies Bond types in adhesive joints The intermolecular bonds (secondary valency bonds) act between the adhesive molecules as well as between adhesive and the surfaces of the joining parts and are thus relevant for the cohesion and adhesion strength (Figure 4701.01.09). Bond Types in Adhesive Joints Bonds Types Chemical Bonds Intermolecular Bonds Homopolar Bonds van-der-Waals Bonds Hydrogen Bonds Dipole Forces Heteropolar Bonds Induction Forces Metallic Bonds Dispersion Forces Source: Habenicht alu Bonds Types in Adhesive Joints 4701.01.09 Training in Aluminium Application Technologies Bond forces in adhesive joints (dipole bonds) Numerous adhesives contain polar molecule groups (dipoles) which have a strong polarising action on the metallic joining parts, the latter being non-polar in themselves. The dipole forces can operate effectively only if these molecule groups can approach to TALAT 4701 8
- 9. within about 0.1 mm of the surface of the joining parts (Figure 4701.01.10). The above is only possible if the adhesive can wet the solid surfaces optimally. Bond Forces in Adhesive Joints (Dipole Bonds) Development of Adhesion Forces Due to Dipole Action Between the Molecules alu Bond Forces in Adhesive Joints (Dipole Bonds) 4701.01.10 Training in Aluminium Application Technologies Bond forces in adhesive joints (hydrogen bonds) Hydrogen bonds are a special form of intermolecular bonds. These are, for example, responsible for the relatively high cohesion strengths of PUR and PA adhesives (Figure 4701.01.11). Principle of the Action of Hydrogen Bonds (Example: Polyamides) H O - CH2 - CH2 - N - C - CH2 - CH2 - CH2 - CH2 - C- N- CH2 - CH2 - CH2 - O H H O -CH2 - CH2 - CH2 - CH2 - N - C - CH2 - CH2 - CH2 - CH2 - C- N- CH2 - O H alu Training in Aluminium Application Technologies Bond Forces in Adhesive Joints (Hydrogen Bonds) 4701.01.11 Hydrogen bonds can also be formed between adhesives and solid surfaces when the latter are oxidised or contain adsorbed hydrogen molecules. TALAT 4701 9
- 10. Failure of adhesive joints The separation of adhesive joints occurs due to the failure of adhesion or cohesion or of both (i.e., mixed adhesion and cohesion failure) (Figure 4701.01.12). Failure of Adhesive Joints Adhesion Failure Cohesion Failure Mixed Failure alu Failure of Adhesive Joints 4701.01.12 Training in Aluminium Application Technologies A cohesion failure is to be strived at. An adhesion failure indicates that the surfaces of the parts to be joint had not been properly pretreated. 4701.02 Classification, Characteristics and Properties of Adhesives • Classification of adhesives • Physically bonding adhesives • Chemically reacting adhesives • Classification of adhesives according to forming reaction and polymer structure • Structure of adhesives • Properties of duromeres • Properties of amorphous thermoplastics • Properties of partly crystalline thermoplastics • Stress-strain curve of AlCuMg2 and an epoxy resin adhesive • Creep properties of adhesive layers • Variation of creep strength with temperature • Temperature stability of different adhesive basis Classification of adhesives In principle, all the listed adhesives can be used for joining metals, albeit with different results and performances. TALAT 4701 10
- 11. Organic ceramic adhesives are a special case of adhesives which have to be hardened at high temperatures, deliver relatively low strengths but can withstand high operating temperatures (Figure 4701.02.01). Classsification of Adhesives Organic Adhesives Inorganic Adhesives (Natural and Synthetic Compounds) (Mostly Mineral Basis) Mixed Classification (i.e., Silicon Resins) Physically Bond Chemically Reacting Physically Bond or Adhesives Adhesives Chemically Reacting Combined Adhesives Source: Köhler alu Classification of Adhesives 4701.02.01 Training in Aluminium Application Technologies Physically bonding adhesives Pressure sensitive adhesives and melting adhesives of the physically bonding types can be used efficiently and should receive, therefore, special consideration (Figure 4701.02.02). Physically Bond Adhesives Adhering Adhesives Adhesive Solutions Contact Adhesives Melting Adhesives Plastic Based (On Base Material) (Solvent or H O) (Ventilation Time) (Heat Required) One-Sided One-Sided Double-Sided One-Sided One-Sided Application Application Application Application Application Pressure Necessary Pressure Necessary Short-Time high Contact Pressure Contact Pressure Pressure Hardening Cold Hardening Hot Hardening by Cooling Single-Component Adhesives Source: Köhler alu Physically Bond Adhesives 4701.02.02 Training in Aluminium Application Technologies TALAT 4701 11
- 12. Chemically reacting adhesives Chemically reacting adhesives of the synthetical organic type are, for example, phenolic resins (PR), epoxy resins (ER), unsaturated polyester resins (UP), polyurethanes (PUR), cyanoarcylates (CA) and methylacrylates (MA) (Figure 4701.02.03). Classification of Adhesives Volatile Components without Cracking Volatile Components (Polymerisation and by Cracking Polyaddition Products) Contact Pressure High Pressure Necessary Mechanism of Reaction Hardener Exclusion of Air Humidity Separate Hardener Hardener Additive Heat; Light; and Heat and Metal Contact (i.e. CA; "No-Mix" (i.e. EP; UP; US or HF (i.e. Mod. (i.e. MA) SI; PUR) (Primer, Activator) MA; PUR) EP and UP) Warm Warm Cold Hardening Cold Hardening Hardening Hardening Single-Component Adhesive 2- or Multi-Component Adhesive Source: Köhler alu Chemically Reacting Adhesives 4701.02.03 Training in Aluminium Application Technologies Classification of adhesives according to forming reaction and polymer structure Polymerisation is an exothermic process in which monomers link together to form macromolecules by the breaking of the double bonds of the C atoms, without cracking to by-products. Thermoplastics are produced exclusively. During polycondensation, water is the most common by-product produced. Both thermoplastics as well as thermosetting plastics are produced. During polyaddition, the water atoms are only rearranged. Even here, thermoplastics as well as thermosetting plastics are produced (Figure 4701.02.04). TALAT 4701 12
- 13. Classification of Adhesives Synthetic Adhesives Polymerisation Polyaddition Polycondensation Duromeres Duromeres Duromeres unknown Epoxy Resins Phenol Formaldyde Polyurethane Resins (Cross-Linked) Cresol Resins Resorcin Resins Urea Resins Melamine Resins Polybenzimidazole Thermoplastics Thermoplastics Polymide Polyester Unsaturated Silicone Cycan Acrylate Polyurethane (Linear) Anaerobic Adhesives Mathylacrylates Polyvinyl Acetate Thermoplastics Polyvinyl Alcohol Ethylene Vinyl Acetate Polyvinyl Chloride Polyamide Rubber Polymeres Polyesther Saturated Ethylene Acrylic Acid Cop. Polysulfone Source: Habenicht Classification of Adhesives According to alu Forming Reaction and Polymer Structure 4701.02.04 Training in Aluminium Application Technologies Structure of adhesives Thermosetting plastics - The basic molecules cross-link across a number of free main valencies to a spatial molecule structure. This results in high strengths and rigidities. Thermoplastics have a linear molecular structure (string-like macromolecules). A large number of molecule strings are held together by physical secondary valency bonds. Amorphous thermoplastics have a "cotton wool" structure. In semi-crystalline thermoplastics, parts of the microstructure depict a definite structural arrangement so that the attractive forces in these regions are more intensive than in the amorphous areas (Figure 4701.02.05). TALAT 4701 13
- 14. Structure of Adhesives Duromere Thermoplastic Thermoplastic Cross-Linked String Molecules String Molecules Molecules Amorphous Amorphous Partly Crystalline Construction of Polymer Structures of Monomeres Source: Habenicht alu Structure of Adhesives 4701.02.05 Training in Aluminium Application Technologies Properties of duromeres Properties of Adhesive Layer E Modulus of Elasticity E sB B e Total Elongation Tensile Strength sB Decomposition Temperature Range eB Temperature [ T ] Strength Parameters of Duromeres as a Function of Temperature alu Properties of Duromeres 4701.02.06 Training in Aluminium Application Technologies With increasing temperature up the decomposition temperature, the tensile strength and modulus of elasticity of the thermosetting plastics falls only slightly but the elongation increases somewhat (Figure 4701.02.06). Properties of amorphous thermoplastics With increasing temperature, the tensile strength and modulus of elasticity of the thermoplastics fall almost uniformly with the elongation increasing at the same time. On TALAT 4701 14
- 15. reaching the glass-transition-temperature region, there is a rapid fall in tensile strength accompanied by a sudden increase in elongation. A further increase in temperature leads to a maximum in elongation, with the strength approaching zero. Increasing the temperature further causes the elongation to fall (Figure 4701.02.07). Properties of Amorphous Thermoplastics E Modulus of Elasticity, E sB Tensile Strength, sB Total Elongation, eB Glassy Entropy- Flow Decomposition State Elastic Region Temperature Range Region eB Temperature, T Glass Transition Region Strength Parameters of Amorphous Thermoplastics as a Function of Temperature alu Properties of Amorphous Thermoplastics 4701.02.07 Training in Aluminium Application Technologies Properties of partly crystalline thermoplastics The glass-transition-temperature region, which in the case of amorphous thermoplastics is higher than the practical operational temperature, lies by about 0 °C for the semi- crystalline thermoplastics. At the melting region of the crystals, these thermoplastics lose their form. This is the reason for the higher modulus of elasticity and the insensitivity of the semi-crystalline thermoplastics to impact loadings (Figure 4701.02.08). TALAT 4701 15
- 16. Properties of Adhesive Layers E Modulus of Elasticity, E Tensile Strength, sB Total Elongation, eB sB Glassy Entropy- Flow Decomposition State Elastic Region Temperature Range Region eB Glass Crystallites Temperature, T Transition Melting Region Region Strength Parameters of Partly Crystalline Thermoplastics as a Function of Temperature alu Properties of Partly Crystalline Thermoplastics 4701.02.08 Training in Aluminium Application Technologies Stress-strain curve of AlCuMg2 and an epoxy resin adhesive Adhesives exhibit a deformation behaviour very different to that of the metallic parts being joined. Although the material AlCuMg2 still behaves elastically up to tensile stresses of about 200 N/mm2 due to its modulus of elasticity, the linear correlation between stress and strain is valid for only a very narrow region for the adhesive layer. Characteristic for most polymers is the fact that the major part of the stress-strain curve is non-linear and that the individual polymers exhibit very different stress-strain behaviours among themselves (Figure 4701.02.09). Properties of Adhesive Layers AlCuMg2 300 Stress, σ 200 100 Epoxy Resin Adhesive 0 10 20 30 40 % Strain, ε alu Stress-Strain Curve of AlCuMg2 and 4701.02.09 Training in Aluminium Application Technologies an Epoxy Resin Adhesive TALAT 4701 16
- 17. Creep properties of adhesive layers The tendency of adhesives to creep is the main factor governing the time-temperature behaviour of the adhesive joint. Creep can be defined as the time-dependent increase in length of viscoelastic substances subject to a constant tensile load, whereby an asymptotical load-dependent limiting value of elongation is reached. Creep Properties of Adhesive Layer 3 Creep Strain [ V ] 2 1 Time [ t ] Schematic Illustration of the Creep Strain of Adhesives Source: Späth alu Creep Properties of Adhesive Layer 4701.02.10 Training in Aluminium Application Technologies A typical creep curve exhibits 3 stages of creep (Figure 4701.02.10): − Primary (transient) creep: - elastic deformation of molecules - rupture of secondary valency bonds and rearrangement of linked-chain segments - no plastic deformation. − Secondary (stationary) creep: - constant creep rate - equilibrium between the competing processes of rupture and creation of new bonds within the molecule aggregate. − Tertiary (accelerated) creep: - rupture of adhesive joint initiated - deformation limit of adhesive layer reached. Variation of creep strength with temperature The hardened adhesive layers of the best-known base substances (i.e., phenolic resins, epoxy resins, epoxy nylons, polyurethane) exhibit a strength behaviour within large regions of temperatutes similar to the one shown in Figure 4701.02.11. TALAT 4701 17
- 18. Strength Properties of Adhesive Layers N/mm² 50 Adhesive Joint Strength, τB 40 30 20 10 -250 -200 -150 -100 -50 0 50 100 150 200 250 °C Temperature t alu Variation of Adhesive Joint Strength withTemperature 4701.02.11 Training in Aluminium Application Technologies At low temperatures, the strength of the adhesive layer rises only slightly with temperature (glassy state) until the strength reaches a peak value which, depending on the structure, can extend over a large temperature range. Due to the increased plasticity of the adhesive layer, stress peaks occurring at the ends of the overlaps can be reduced. At still higher temperatures a flow and decomposition process sets in, causing the strength of the adhesive layer to fall. Temperature stability of different adhesive basis The values given in Figure 4701.02.12 are the maximum upper temperature ranges for the operating condition. These can, however, only serve as rough estimates for limiting values under operating conditions. Special modifications can be used to attain still higher limiting values. Properties of Adhesives Adhesive Base Temperature Range °C Epoxy Dicyanodiamide ( Warm Hardening ) 110 ... 130 Epoxy Polyamide ( Cold Hardening ) 60 ... 90 Phenolic Resins ( Warm Hardening ) 80 ... 120 Polymethyl Methylacrylate ( Cold Hardening ) 80 ... 100 Polyurethanes 80 ... 100 Polyesther 60 ... 80 Cyanoacrylate 70 ... 80 Polydiacrylacidester ( Anaerobic Hardening ) 120 ... 150 Polyamides 120 ... 140 Polyimide 200 ... 300 RTV - Silicones 180 ... 190 alu Temperature Stability of Different Adhesive Basis 4701.02.12 Training in Aluminium Application Technologies TALAT 4701 18
- 19. 4701.03 Literature/References 1. Habenicht, G.: Kleben. Springer-Verlag Berlin-Heidelberg-New York 1990. 2. Fauner, G., Endlich, W.: Angewandte Klebtechnik. Carl Hanser Verlag, München-Wien 1979. 3. Jenckel, E., Rumbach, B.: Adsorption von hochmolekularen Stoffen aus der Lösung. J. Elektrochem. 55 (1951) pp. 612-618. 4. Köhler, R.: Zur Systematik der Klebstoffe. Adhäsion 8 (1964) S. 160-164. 5. Späth, W.: Gummi und Kunststoffe, Beiträge zur Technologie der Hochpolymeren. Gentner, Stuttgart 1956. 6. Brockmann, W., Dorn, L. und Käufer, H.: Kleben von Kunststoff mit Metall. Springer -Verlag Berlin-Heidelberg-New York 1989. 7. VDI-Richtlinie 2229: Metallkleben. Ausgabe Juni 1979. VDI-Verlag Düsseldorf 1979. 8. Matting, A.: Metallkleben. Springer-Verlag Berlin 1969. 9. Schliekelmann, R.J.: Metallkleben - Konstruktion und Fertigung in der Praxis. DVS Verlag Düsseldorf 1972 TALAT 4701 19
- 20. 4701.04 List of Figures Figure No. Figure Title (Overhead) 4701.01.01 Adhesive Bonding of Aluminium 4701.01.02 Classification of Adhesive Bonding 4701.01.03 Load Distribution at Joints 4701.01.04 Advantages and Disadvantages of Adhesive Joining 4701.01.05 Structure of an Adhesive Joint 4701.01.06 Adhesion and Cohesion 4701.01.07 Correlation between Wetting Angle and Behaviour of Adhesives 4701.01.08 Mechanism of Deposition of Macromolecules on Surfaces 4701.01.09 Bond Types in Adhesive Joints 4701.01.10 Bond Forces in Adhesive Joints (Dipole Bonds) 4701.01.11 Bond Forces in Adhesive Joints (Hydrogen Bonds) 4701.01.12 Failure of Adhesive Joints 4701.02.01 Classification of Adhesives 4701.02.02 Physically Bond Adhesives 4701.02.03 Chemically Reacting Adhesives 4701.02.04 Classification of Adhesives According to Forming Reaction and Polymer Structure 4701.02.05 Structure of Adhesives 4701.02.06 Properties of Duromeres 4701.02.07 Properties of Amorphous Thermoplastics 4701.02.08 Properties of Partly Crystalline Thermoplastics 4701.02.09 Stress-Strain Curve of AlCuMg2 and an Epoxy Resin Adhesive 4701.02.10 Creep Properties of Adhesive Layer 4701.02.11 Variation of Adhesive Joint Strength with Temperature 4701.02.12 Temperature Stability of Different Adhesive Basis TALAT 4701 20