{"id":111269,"date":"2025-12-18T07:14:26","date_gmt":"2025-12-18T06:14:26","guid":{"rendered":"https:\/\/www.linseis.com\/?p=111269"},"modified":"2026-01-09T13:58:48","modified_gmt":"2026-01-09T12:58:48","slug":"thermal-dilataion-difference-in-bonded-joints-challenges-and-solutions-for-reliable-bonded-joints","status":"publish","type":"post","link":"https:\/\/www.linseis.com\/en\/wiki\/thermal-dilataion-difference-in-bonded-joints-challenges-and-solutions-for-reliable-bonded-joints\/","title":{"rendered":"Thermal dilatation difference in bonded joints: Challenges and solutions for reliable bonded joints"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"111269\" class=\"elementor elementor-111269 elementor-111229\" data-elementor-post-type=\"post\">\n\t\t\t\t<div class=\"elementor-element elementor-element-b75441f e-flex e-con-boxed e-con e-parent\" data-id=\"b75441f\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t<div class=\"elementor-element elementor-element-35d541b e-con-full e-flex e-con e-child\" data-id=\"35d541b\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-97683da elementor-toc--minimized-on-tablet elementor-widget elementor-widget-table-of-contents\" data-id=\"97683da\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;headings_by_tags&quot;:[&quot;h2&quot;],&quot;exclude_headings_by_selector&quot;:[],&quot;no_headings_message&quot;:&quot;No headings were found on this page.&quot;,&quot;marker_view&quot;:&quot;numbers&quot;,&quot;minimize_box&quot;:&quot;yes&quot;,&quot;minimized_on&quot;:&quot;tablet&quot;,&quot;hierarchical_view&quot;:&quot;yes&quot;,&quot;min_height&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:&quot;&quot;,&quot;sizes&quot;:[]},&quot;min_height_tablet&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:&quot;&quot;,&quot;sizes&quot;:[]},&quot;min_height_mobile&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:&quot;&quot;,&quot;sizes&quot;:[]}}\" data-widget_type=\"table-of-contents.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<div class=\"elementor-toc__header\">\n\t\t\t\t\t\t<h4 class=\"elementor-toc__header-title\">\n\t\t\t\tTable of contents\t\t\t<\/h4>\n\t\t\t\t\t\t\t\t\t\t<div class=\"elementor-toc__toggle-button elementor-toc__toggle-button--expand\" role=\"button\" tabindex=\"0\" aria-controls=\"elementor-toc__97683da\" aria-expanded=\"true\" aria-label=\"Open table of contents\"><svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-chevron-down\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M207.029 381.476L12.686 187.132c-9.373-9.373-9.373-24.569 0-33.941l22.667-22.667c9.357-9.357 24.522-9.375 33.901-.04L224 284.505l154.745-154.021c9.379-9.335 24.544-9.317 33.901.04l22.667 22.667c9.373 9.373 9.373 24.569 0 33.941L240.971 381.476c-9.373 9.372-24.569 9.372-33.942 0z\"><\/path><\/svg><\/div>\n\t\t\t\t<div class=\"elementor-toc__toggle-button elementor-toc__toggle-button--collapse\" role=\"button\" tabindex=\"0\" aria-controls=\"elementor-toc__97683da\" aria-expanded=\"true\" aria-label=\"Close table of contents\"><svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-chevron-up\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M240.971 130.524l194.343 194.343c9.373 9.373 9.373 24.569 0 33.941l-22.667 22.667c-9.357 9.357-24.522 9.375-33.901.04L224 227.495 69.255 381.516c-9.379 9.335-24.544 9.317-33.901-.04l-22.667-22.667c-9.373-9.373-9.373-24.569 0-33.941L207.03 130.525c9.372-9.373 24.568-9.373 33.941-.001z\"><\/path><\/svg><\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<div id=\"elementor-toc__97683da\" class=\"elementor-toc__body\">\n\t\t\t<div class=\"elementor-toc__spinner-container\">\n\t\t\t\t<svg class=\"elementor-toc__spinner eicon-animation-spin e-font-icon-svg e-eicon-loading\" aria-hidden=\"true\" viewBox=\"0 0 1000 1000\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M500 975V858C696 858 858 696 858 500S696 142 500 142 142 304 142 500H25C25 237 238 25 500 25S975 237 975 500 763 975 500 975Z\"><\/path><\/svg>\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-6854051 elementor-widget elementor-widget-spacer\" data-id=\"6854051\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-30dbdc1 elementor-widget elementor-widget-heading\" data-id=\"30dbdc1\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">The central challenge in hybrid lightweight construction<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f563fb9 elementor-widget elementor-widget-text-editor\" data-id=\"f563fb9\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>In modern design concepts for <a href=\"https:\/\/www.linseis.com\/en\/applications\/automotive-aviation-aerospace\/\"><strong>automotive, aerospace<\/strong><\/a> and electronics, hybrid assemblies made of various lightweight materials such as aluminum, steel and carbon fiber reinforced plastics (CFRP) are increasingly being joined using adhesive bonding technology. This joining technology enables two-dimensional force transmission and design-optimized geometries, but faces a central technical challenge: different thermal expansion coefficients between the joining partners and adhesives. This so-called delta-alpha problem (delta-a problem) can lead to internal stresses and critical failure mechanisms, particularly under cyclical or process-related temperature loads (European Aluminum Association 2015; Dietrich 2018).  <\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-89c0869 elementor-widget elementor-widget-spacer\" data-id=\"89c0869\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f89eb30 elementor-widget elementor-widget-heading\" data-id=\"f89eb30\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Material-specific thermal expansion coefficients and their effects<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-36f5a88 elementor-widget elementor-widget-spacer\" data-id=\"36f5a88\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-035f339 elementor-widget elementor-widget-text-editor\" data-id=\"035f339\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>Each material has a characteristic <a href=\"https:\/\/www.linseis.com\/en\/properties\/linear-expansion-coefficient\/\" data-auto-event-observed=\"true\"><strong>coefficient of thermal expansion (\u03b1)<\/strong><\/a>&nbsp;which describes the change in length as a function of temperature. The range of these values varies considerably between the materials used in mixed construction joints: steel has values of \u03b1 \u2248 11.5-13.1 \u00d7 10-\u2076 K-\u00b9, while aluminum has significantly higher expansion coefficients of \u03b1 \u2248 22-25 \u00d7 10-\u2076 K-\u00b9. Epoxy resin adhesives are in the range of \u03b1 \u2248 45-200 \u00d7 10-\u2076 K-\u00b9, and CFRP composites show strongly anisotropic expansion properties with values between -1.0 and 1.5 in fiber orientation and up to 65 \u00d7 10-\u2076 K-\u00b9 transverse to the fiber orientation.<\/p>\n<p>fiber (Dietrich 2018).<br>The resulting relative displacements and stresses that occur during temperature cycles &#8211; for example during production processes or during operation in the temperature range from -40 \u00b0C to +200 \u00b0C &#8211; place considerable strain on the bonded joint. Particularly critical are areas close to the glass transition temperature (Tg), in which adhesives change from viscoelastic to elastic or plastic properties, which can have a significant impact on the joint strength and service life (DFR Solutions n.d.).<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ac9afd3 elementor-widget elementor-widget-spacer\" data-id=\"ac9afd3\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1b982d6 elementor-widget elementor-widget-heading\" data-id=\"1b982d6\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Damage mechanisms and their technical consequences<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5df331d elementor-widget elementor-widget-text-editor\" data-id=\"5df331d\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>The damage to bonded joints caused by different thermal expansion coefficients manifests itself through various mechanisms. Different \u03b1-values result in shear and tensile stresses, which can lead to both interface failure and cohesion fracture in the adhesive itself. Adhesive gap thickness and component dimension are decisive factors for the stress distribution. (European Aluminum Association 2015; NPL 1999).   <br>Particularly with CFRP joints, the anisotropy of the expansion must be taken into account, so that the laminate structure and fiber orientation also significantly influence the stress development. This must be taken into account when designing lightweight structures and composites, as the thermal stress is caused both by the mismatch of the joining partners and by the contraction of the adhesive during curing (Dietrich 2018). <\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-636a704 elementor-widget elementor-widget-spacer\" data-id=\"636a704\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c3e057f elementor-widget elementor-widget-spacer\" data-id=\"c3e057f\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1443f70 elementor-widget elementor-widget-heading\" data-id=\"1443f70\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Moisture as an additional influencing factor<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1dcd72b elementor-widget elementor-widget-spacer\" data-id=\"1dcd72b\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7a2ebce elementor-widget elementor-widget-text-editor\" data-id=\"7a2ebce\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>In combination with temperature, moisture is a decisive additional factor influencing the joint strength. It can significantly change the mechanical properties of adhesives, weaken adhesion to the substrate and accelerate age-related damage such as delamination, cracking or adhesive layer deformation. The interaction with temperature increases diffusion and the hydrolytic degradation process in the adhesive, especially in outdoor applications and electronic components.  <\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ac47d19 elementor-widget elementor-widget-spacer\" data-id=\"ac47d19\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d274b60 elementor-widget elementor-widget-image\" data-id=\"d274b60\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img fetchpriority=\"high\" decoding=\"async\" width=\"800\" height=\"450\" src=\"https:\/\/www.linseis.com\/wp-content\/uploads\/2025\/11\/217-1024x576.png\" class=\"attachment-large size-large wp-image-111255\" alt=\"\" srcset=\"https:\/\/www.linseis.com\/wp-content\/uploads\/2025\/11\/217-1024x576.png 1024w, https:\/\/www.linseis.com\/wp-content\/uploads\/2025\/11\/217-300x169.png 300w, https:\/\/www.linseis.com\/wp-content\/uploads\/2025\/11\/217-768x432.png 768w, https:\/\/www.linseis.com\/wp-content\/uploads\/2025\/11\/217.png 1140w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2c36fea elementor-widget elementor-widget-heading\" data-id=\"2c36fea\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Service life prediction and test methods<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2b2fdfa elementor-widget elementor-widget-text-editor\" data-id=\"2b2fdfa\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>The service life of bonded joints under alternating thermal loads can be reliably estimated using a combination of accelerated ageing tests, cyclic temperature tests and modern prediction models. Time-lapse tests simulate long-term loads under realistic temperature cycles in order to simulate the failure behavior and the development of cracks in the adhesive. Modern short-cycle prediction methods such as the Stepped Isothermal Method (SIM) or Stepped IsoStress Method (SSM) allow the rapid determination of creep behavior and relaxation effects in connection with the thermal mismatch of different joining materials (NPL 1999).  <br>Fatigue and thermal shock tests record the number of fatigue cycles and the occurrence of damage mechanisms, which are crucial for service life assessment. Experimental results are increasingly being combined with numerical simulations and established test methods such as climate change tests in order to enable practical service life predictions. <\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b5ee356 elementor-widget elementor-widget-spacer\" data-id=\"b5ee356\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ba8bbc4 elementor-widget elementor-widget-spacer\" data-id=\"ba8bbc4\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a3201b5 elementor-widget elementor-widget-heading\" data-id=\"a3201b5\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Optimized material combinations and adhesive systems<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-eb315fe elementor-widget elementor-widget-spacer\" data-id=\"eb315fe\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f928c96 elementor-widget elementor-widget-text-editor\" data-id=\"f928c96\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>Combinations of adhesive and substrate materials that have similar thermal expansion coefficients are particularly effective in minimizing the risk of thermally induced cracking, delamination or stress formation. Epoxy resin adhesives in combination with metallic substrates such as aluminium or steel are particularly recommended if the adhesive formulation is specifically modified with fillers or flexibilizers in order to reduce the coefficient of expansion. <a href=\"https:\/\/www.linseis.com\/en\/properties\/linear-expansion-coefficient\/\"><strong>expansion coefficient<\/strong><\/a> to that of the metal (European Aluminium Association 2015; Dietrich 2018).<br>Due to their low modulus of elasticity or high elasticity, silicone adhesives and polyurethane systems offer advantageous properties with widely varying thermal expansion coefficients and reduce thermal cracking and fatigue. <\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1476360 elementor-widget elementor-widget-spacer\" data-id=\"1476360\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-db12fe6 elementor-widget elementor-widget-heading\" data-id=\"db12fe6\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Practical solutions and design recommendations<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-49e1970 elementor-widget elementor-widget-text-editor\" data-id=\"49e1970\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>Several factors are crucial for the successful implementation of reliable bonded joints in hybrid lightweight construction. Optimizing the adhesive system with suitable adhesives and flexibilization helps to reduce stresses. The choice of CFRP laminate structure and the optimization of overlap length, adhesive gap thickness and joining geometry are decisive factors. The process control and temperature management should be selected in such a way that critical areas of the glass transition temperature are avoided (DFR Solutions n.d.; NPL 1999).   <\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-08989f3 elementor-widget elementor-widget-spacer\" data-id=\"08989f3\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f7d71d6 elementor-widget elementor-widget-heading\" data-id=\"f7d71d6\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Implications for practice<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d213245 elementor-widget elementor-widget-spacer\" data-id=\"d213245\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-87cc9b4 elementor-widget elementor-widget-text-editor\" data-id=\"87cc9b4\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>There are concrete practical implications for development engineers in automotive and aerospace, material scientists and quality teams. The analysis and simulation of the delta-alpha problem is essential for the design of reliable, durable bonded joints in hybrid lightweight construction. Test methods such as <g id=\"gid_0\"><g id=\"gid_1\">dilatometry<\/g><\/g>, <g id=\"gid_2\"><g id=\"gid_3\">thermomechanical analysis (TMA)<\/g><\/g> and <g id=\"gid_4\"><g id=\"gid_5\">DSC<\/g><\/g> are key tools for benchmarking and process optimization. The validation of thermal cycles is an integral part of any quality and validation strategy (European Aluminium Association 2015; DFR Solutions n.d.).   <\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-85db9ba elementor-widget elementor-widget-spacer\" data-id=\"85db9ba\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e871ffd elementor-widget elementor-widget-spacer\" data-id=\"e871ffd\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-96597bf elementor-widget elementor-widget-heading\" data-id=\"96597bf\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Conclusion<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-af33c7a elementor-widget elementor-widget-spacer\" data-id=\"af33c7a\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a1083f3 elementor-widget elementor-widget-text-editor\" data-id=\"a1083f3\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>The varying degrees of thermal expansion of adhesives and joining parts is a critical factor for the mechanical integrity of modern mixed construction bonded joints. By specifically modifying the adhesive properties, optimizing the component and joining geometry and using established test methods, development engineers can influence the mechanical performance in a targeted manner and minimize the risk of failure (Dietrich 2018; NPL 1999; DFR Solutions n.d.). <\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-62fc32d elementor-widget elementor-widget-spacer\" data-id=\"62fc32d\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5fd8e5d elementor-widget elementor-widget-spacer\" data-id=\"5fd8e5d\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-efdf12b elementor-widget elementor-widget-heading\" data-id=\"efdf12b\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">List of sources<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-bc5a2c1 elementor-widget elementor-widget-spacer\" data-id=\"bc5a2c1\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7ec0ae5 elementor-widget elementor-widget-text-editor\" data-id=\"7ec0ae5\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>Dietrich, R. (2018).  <em>Analysis of the thermal expansion incompatibility of FRP-metal hybrid structures.<\/em>  Technical University of Munich. Available at: <a href=\"https:\/\/mediatum.ub.tum.de\/1393107\" target=\"_blank\" rel=\"noopener\">https:\/\/mediatum.ub.tum.de\/1393107<\/a> <\/p><p>European Aluminum Association (2015). <em>Joining Dissimilar Materials.<\/em> Available at:<br><a href=\"https:\/\/european-aluminium.eu\/wp-content\/uploads\/2022\/11\/11-joining-dissimilar-materials_2015.pdf\" target=\"_blank\" rel=\"noopener\">https:\/\/european-aluminium.eu\/wp-content\/uploads\/2022\/11\/11-joining-dissimilar-materials_2015.pdf<\/a><\/p><p>NPL (1999). <em>Cyclic Fatigue Testing of Adhesive Joints.<\/em> Available at: <a href=\"https:\/\/www.researchgate.net\/publication\/237635154\" target=\"_blank\" rel=\"noopener\">https:\/\/www.researchgate.net\/publication\/237635154<\/a><\/p><p>DFR Solutions (n.d.). <em>Temperature Cycling and Fatigue in Electronics.<\/em> Available at:<br><a href=\"https:\/\/www.ekwb.com\/wp-content\/uploads\/2020\/05\/1-Temperature-Cycling-and-Fatigue-in-Electronics-White-Paper-1.pdf\" target=\"_blank\" rel=\"noopener\">https:\/\/www.ekwb.com\/wp-content\/uploads\/2020\/05\/1-Temperature-Cycling-and-Fatigue-in-Electronics-White-Paper-1.pdf<\/a><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-cec7d2c elementor-widget elementor-widget-spacer\" data-id=\"cec7d2c\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>In modern design concepts for automotive, aerospace and electronics, hybrid assemblies made of various lightweight materials such as aluminum, steel and carbon fiber reinforced plastics (CFRP) are increasingly being joined using adhesive bonding technology.  <\/p>\n","protected":false},"author":15,"featured_media":111244,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":""},"categories":[106],"tags":[],"class_list":["post-111269","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wiki"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.linseis.com\/en\/wp-json\/wp\/v2\/posts\/111269","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.linseis.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.linseis.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.linseis.com\/en\/wp-json\/wp\/v2\/users\/15"}],"replies":[{"embeddable":true,"href":"https:\/\/www.linseis.com\/en\/wp-json\/wp\/v2\/comments?post=111269"}],"version-history":[{"count":0,"href":"https:\/\/www.linseis.com\/en\/wp-json\/wp\/v2\/posts\/111269\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.linseis.com\/en\/wp-json\/wp\/v2\/media\/111244"}],"wp:attachment":[{"href":"https:\/\/www.linseis.com\/en\/wp-json\/wp\/v2\/media?parent=111269"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.linseis.com\/en\/wp-json\/wp\/v2\/categories?post=111269"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.linseis.com\/en\/wp-json\/wp\/v2\/tags?post=111269"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}