Adhesive strength testing service

Adhesive Strength Testing Service – Accredited Bond Performance Evaluation for Czech Manufacturers and Importers

Our internationally accredited laboratory provides a dedicated adhesive strength testing service that gives Czech manufacturers, importers, bonding-system suppliers and quality-assurance managers the independent, traceable data they need to validate the mechanical performance of structural bonds, pressure‑sensitive tapes, laminates and sealants. Every test is performed under our ISO/IEC 17025 accreditation, and each report that carries the ILAC mark is unconditionally accepted by the Czech Trade Inspection Authority, customs offices and all notified bodies within the European Union. The adhesive strength testing service covers the full spectrum of loading modes – tension, shear, peel and cleavage – and quantifies the force, stress, fracture energy and failure mode of the bond. For a Czech automotive supplier qualifying a new crash‑durable adhesive, a converter of self‑adhesive labels for the Prague packaging industry, or an importer of construction adhesives for the booming Czech residential market, these measurements provide the legally robust foundation for CE marking under the Construction Products Regulation, for the issue of inspection certificates according to ČSN EN 10204, and for the technical-file documentation required by the relevant harmonised standards and customer specifications.

Product Samples We Regularly Subject to Adhesive Strength Testing

The test frames, environmental chambers and specimen‑preparation tools in our facility can handle everything from small single‑lap‑shear coupons to full‑scale bonded assemblies. The following categories represent the most frequently tested items:

Structural adhesives and metal‑bonding systems – single‑component heat‑cure epoxies, two‑component acrylics and polyurethanes, and toughened adhesives for steel, aluminium and galvanised substrates
Plastic and composite bonded joints – bonded polypropylene, polyamide, carbon‑fibre‑reinforced polymer and glass‑fibre‑reinforced polymer specimens, including plasma‑ or primer‑treated surfaces
Pressure‑sensitive adhesive tapes and films – double‑sided foam tapes, transfer tapes, masking tapes, duct tapes and clear mounting tapes for indoor and outdoor use
Labels, decals and graphic films – self‑adhesive paper and film labels, in‑mould labels and promotional stickers for Czech consumer‑goods packaging
Laminates and multilayer composites – flexible packaging laminates, photovoltaic back‑sheets and automotive interior laminates
Construction and assembly adhesives – cartridge‑dispensed polyurethane and MS‑polymer adhesives for timber, concrete, ceramic and metal, including anchors and dowel‑bonding mortars
Sealants and elastic bond lines – silicone, polyurethane and hybrid sealants for façades, insulating glass units and sanitary applications
Wood adhesives and glued timber joints – urea‑formaldehyde, melamine‑urea‑formaldehyde, phenolic and one‑component polyurethane adhesives for load‑bearing and non‑load‑bearing timber structures

Adhesive Tensile Shear Strength Testing – Lap‑Shear Evaluation According to EN 1465 and ISO 4587

Determination of tensile lap‑shear strength of rigid‑to‑rigid bonded assemblies according to ČSN EN 1465 (ISO 4587): a single‑overlap joint specimen prepared from two rigid adherends – typically aluminium, steel, composite or plastic – is loaded in tension at a constant test speed. The shear stress at failure is calculated from the maximum force and the bonded area, and the type of failure – cohesive within the adhesive, adhesive at the interface, or substrate failure – is visually estimated and reported. This is the most frequently requested adhesive strength testing service for Czech industrial bonding applications, and it directly supports the qualification of adhesives for structural steelwork and transport vehicles.
Shear strength of bonded plastic and composite joints according to ASTM D3163 and internal procedures based on EN 1465: the standard lap‑shear method is adapted for flexible and anisotropic adherends, with special attention to the alignment of the reinforcement direction. The shear strength and the fracture path through the laminate or the adhesive layer are reported, and the data are used by Czech automotive tier‑1 suppliers to validate the bonding of glass‑fibre‑reinforced brackets and spoilers.
Shear stress‑strain behaviour and stiffness of the bond line using extensometry: a non‑contact video extensometer or a clip‑on gauge measures the relative displacement of the adherends during the lap‑shear test. The shear modulus of the adhesive and the elastic limit of the joint are calculated and included in the report, enabling the finite‑element analyst to model the joint with the correct constitutive data.
Temperature‑ and rate‑dependent shear strength: the lap‑shear test is performed inside a thermal chamber at temperatures from -40 °C to +150 °C, and at test speeds from 0.5 mm/min to 500 mm/min. The influence of temperature and loading rate on the failure load and the failure mode is mapped, giving Czech design engineers the envelope of safe operating conditions for bonded components.

Peel Strength Testing – Floating‑Roller, T‑Peel and 180‑Degree Peel According to ISO 4578, ISO 11339 and EN 1939

Floating‑roller peel resistance of adhesives according to ČSN EN 1464 (ISO 4578): a flexible adherend is peeled from a rigid one at a constant angle maintained by a floating‑roller fixture. The steady‑state peel force per unit width is reported in newtons per millimetre. This test is the standard method for evaluating the peel performance of structural adhesives on metal skins, and it is widely specified by Czech rail‑vehicle and trailer manufacturers.
T‑peel test for flexible‑to‑flexible bonded assemblies according to ČSN EN ISO 11339: two flexible strips bonded face‑to‑face are pulled apart in a T‑configuration, and the peel force is recorded. The test simulates the loading on a flexible packaging seal, a textile laminate or a shoe‑sole bond, all of which are important product groups for Czech converters and footwear producers.
180‑degree peel test for pressure‑sensitive adhesive tapes and films according to ČSN EN 1939: the tape is applied to a standard stainless‑steel panel with a controlled roller, conditioned for a defined dwell time, and then peeled back upon itself at 180° and a constant speed of 300 mm/min. The average peel adhesion and the pattern of any adhesive transfer or jerky slip‑stick behaviour are reported. This adhesive strength testing service is the primary quality‑control tool for Czech importers of mounting tapes and for label converters serving the Czech retail market.
90‑degree and variable‑angle peel for specific design geometries: using a motorised sliding‑stage peel fixture, the peel angle can be set to any value between 30° and 180° to replicate the actual loading on a bonded bracket or an automotive trim strip. The peel force as a function of angle is measured, and the data are fed into the design validation of the joint.
Loop‑tack and quick‑stick measurement for pressure‑sensitive adhesives: a loop of tape is brought into contact with a substrate and immediately withdrawn without a dwell period. The maximum force recorded during debonding is reported as the loop tack. The test simulates the initial grab of a label or a tape on a production line and is widely used by Czech converters to check the batch‑to‑batch consistency of the adhesive.

Tensile Bond Strength, Pull‑Off and Cleavage Testing – Through‑Thickness and Butt‑Joint Evaluation

Determination of the tensile strength of butt joints according to ČSN EN 15870 (ISO 6922): two cylindrical adherends are bonded end‑to‑end, and the assembly is pulled in pure tension until failure. The tensile strength of the bond and the fracture surface are reported. This test is particularly important for adhesives used to bond threaded studs, inserts and stand‑offs in Czech electronic and furniture manufacturing.
Pull‑off adhesion of coatings, sealants and repair mortars according to ČSN EN 1542 and ČSN EN ISO 4624: a dolly is glued to the surface of the cured adhesive or the coating, and a portable pull‑off tester applies a tensile force perpendicular to the surface until detachment occurs. The pull‑off strength in megapascals and the nature of the fracture – within the adhesive, at the interface or within the substrate – are recorded. Czech construction‑site inspectors and repair‑mortar manufacturers use this test to verify the bond of overlays, screeds and protective coatings.
Cleavage strength under wedge impact according to ISO 11343: a wedge is driven into the bond line of a lap‑joint specimen at high speed, and the energy required to propagate the crack is measured. The test characterises the crash resistance of toughened structural adhesives and is specified by Czech automotive OEMs for the qualification of adhesives used in energy‑absorbing body joints.
Bond strength of wood adhesives in shear by compressive loading according to ČSN EN 205 and ČSN EN 302-1: a small lap‑shear specimen cut from a bonded beech or spruce joint is loaded in compression to shear the glue line. The shear strength and the percentage of wood failure are determined and compared with the minimum values required for the durability class. Czech glulam and window manufacturers use this test to certify their adhesives for load‑bearing and exterior applications.

Durability, Ageing and Fatigue – Adhesive Strength Testing After Environmental Exposure

Residual strength after exposure to heat, humidity and water immersion: bonded specimens are conditioned in a climatic chamber at elevated temperature and humidity – for example, 40 °C and 95 % relative humidity – or immersed in water at 23 °C or boiling water for prescribed periods. The lap‑shear, peel or tensile strength is then measured and compared with the unaged value. The retention factor is reported, and the data are used by Czech specifiers to assess the long‑term durability of the bond in Central European service environments.
Strength after salt‑spray exposure and cyclic corrosion testing: specimens are exposed to a neutral salt spray according to ČSN EN ISO 9227 or to the cyclic corrosion test of ČSN EN ISO 11997-1 before the mechanical test. This adhesive strength testing service is mandatory for adhesives used in automotive under‑bonnet and exterior applications and for bonded aluminium profiles in Czech architectural façades.
Creep rupture and static load resistance of adhesive bonds: a constant shear load – typically a percentage of the short‑term failure load – is applied to a lap‑joint specimen for 1 000 hours or longer. The time to rupture or the accumulated creep displacement is recorded, and the results are used to determine the safe working stress for a bonded joint that must support a permanent load, such as a bonded glass fin or a structural silicone seal on a Czech office building.
Fatigue strength under cyclic loading according to ISO 9664: lap‑shear or butt‑joint specimens are subjected to a sinusoidal tensile‑tensile or tensile‑shear load at a defined frequency and load ratio. The number of cycles to failure is recorded at several load levels, and an S‑N curve is constructed. Czech manufacturers of bonded bicycle frames, machine guards and railway interior panels use the fatigue data to define the inspection interval and the design life of the bonded assembly.
Bond durability after UV radiation and artificial weathering: transparent and semi‑transparent adhesive joints are exposed to xenon‑arc or fluorescent‑UV radiation combined with moisture cycles according to ČSN EN ISO 4892-2. The change in appearance, the loss of adhesion and the reduction in mechanical strength are quantified, providing the Czech façade and signage industry with the evidence that the bond will remain functional under years of direct sunlight.

Report Acceptance and Regulatory Compliance for the Czech Republic

All measurements performed within our adhesive strength testing service are executed under the fully accredited scope of our ISO/IEC 17025 quality management system. Each test report that carries the ILAC mark is therefore automatically recognised by the Czech Trade Inspection Authority, the Technical Inspection of the Czech Republic, customs offices and all notified bodies in the European Union. For Czech bonding‑system suppliers, adhesive importers, construction‑product manufacturers and automotive component producers, the report constitutes legally robust evidence that the bonded joint meets the strength and durability requirements of the applicable harmonised standards, customer specifications and the essential requirements of the Construction Products Regulation. The documentation can be directly used to issue inspection certificates according to ČSN EN 10204, to support CE marking, to compile the technical file for type examination, and to provide an indisputable basis in warranty claims and commercial disputes concerning the performance of adhesives and bonded products.