Right-angle tear load testing service

Right-Angle Tear Load Testing Service – Accredited ISO/IEC 17025 Tear Strength Assessment for the Croatian Market

Right-angle tear load testing is a critical mechanical evaluation method used to measure the resistance of materials, films, sheets, fabrics, and laminates to tearing forces perpendicular to the material's surface. This property is essential for ensuring the durability, reliability, and safety of products used in packaging, medical devices, automotive interiors, textiles, flexible electronics, and construction membranes, where resistance to propagation of existing tears or sharp notches is a key performance requirement. In the Croatian market, where the Hrvatski zavod za norme (HZN), the Državni inspektorat, the Ministarstvo gospodarstva i održivog razvoja, and the Carinska uprava enforce strict quality, safety, and performance standards aligned with EU directives and HRN EN (Croatian standards based on European norms), the accurate evaluation of right-angle tear load is essential for product certification, supplier qualification, type testing, quality control in manufacturing, and import-export processes. Our laboratory offers a comprehensive right-angle tear load testing service, applying standardized methods such as ASTM D1004, ISO 13937-3, DIN 53363, EN 21974, and HRN EN ISO 13937-3 to measure tear force, tear resistance, and tear propagation characteristics under controlled loading conditions. All tests are performed under our ISO/IEC 17025 (CNAS) accreditation, and the resulting reports are fully accepted by Croatian authorities and notified bodies, making them indispensable for regulatory compliance, product validation, and market access in Croatia and the European Union.

Material and Product Samples We Regularly Test

Our laboratory receives a wide variety of materials and products for right-angle tear load testing. Typical samples include:

• Plastic films and sheets – polyethylene (PE), polypropylene (PP), PVC, polyester (PET), polyamide (PA), and bioplastics for flexible packaging and industrial applications.
• Textiles and nonwovens – woven, knitted, and nonwoven fabrics for automotive interiors, protective clothing, and geotextiles.
• Rubber and elastomeric materials – natural rubber, EPDM, silicone, and neoprene for seals, gaskets, and hoses.
• Paper and paperboard – for packaging, printing, and corrugated board applications.
• Coated fabrics and laminates – for automotive, marine, and construction applications.
• Composite materials – fiber-reinforced plastics and laminates for aerospace and structural applications.
• Flexible electronics and adhesive tapes – for electronic device assembly and bonding applications.
• Prototype and new material formulations – submitted by manufacturers for validation of tear resistance before series production.
• Field-retrieved components – for failure analysis and remaining life assessment.

Right-Angle Tear Load Measurement – Standard Methods and Procedures

Right-angle tear load testing measures the force required to propagate a tear in a material starting from a pre-cut notch. The test specimen is shaped like a "trouser leg" or a "right-angle" configuration, and the tear is initiated and propagated by pulling the two legs of the specimen apart. Our tests follow international standards and the requirements of the Croatian packaging, automotive, and textile industries.

• Right-angle tear test for films and sheets (ASTM D1004 / ISO 13937-3 / NTC 5600 – for plastic films and sheets) – we cut a rectangular specimen (typically 50 mm × 50 mm) with a pre-cut slit (a 20 mm long notch) in the center. The specimen is mounted in a universal testing machine with the two legs of the slit clamped in the upper and lower grips. The specimen is pulled apart at a constant speed (typically 50 mm/min). The maximum force required to propagate the tear is recorded. We report the maximum tear force (in N), the tear resistance (in N/mm or N/μm), and the force-displacement curve.
• Right-angle tear test for textiles and fabrics (ISO 13937-3 / EN 21974 / HRN EN ISO 13937-3 / NTC 5601 – for woven and nonwoven fabrics) – we cut a rectangular specimen (typically 200 mm × 100 mm) with a pre-cut slit. The specimen is placed in a tear tester (or a universal testing machine) and the tear is propagated across the specimen. The force required to propagate the tear is recorded. We report the tearing force (in N) and the tear resistance (in N/mm).
• Trouser tear test (ASTM D1938 / ISO 6383-1 / NTC 5602 – for films and flexible materials) – we cut a specimen in the shape of a trouser leg (with two legs of equal width) and clamp the two legs in the testing machine. The specimen is pulled apart, and the force required to propagate the tear is measured. We report the tear force and the tear resistance.
• Right-angle tear test at different speeds (NTC 5603 – for the speed‑dependence evaluation) – we perform the right-angle tear test at different crosshead speeds (e.g., 10 mm/min, 50 mm/min, 100 mm/min, 500 mm/min) to evaluate the speed‑dependence of the tear resistance. We report the tear force at each speed and the speed‑sensitivity curve.
• Right-angle tear test at different temperatures (NTC 5604 – for the thermal effect) – we perform the right-angle tear test at elevated temperatures (e.g., 40 °C, 60 °C) or at low temperatures (e.g., -10 °C, -20 °C) using a temperature‑controlled chamber, to evaluate the effect of temperature on the tear resistance. We report the tear force at each temperature and the temperature coefficient.

Evaluation of Tear Propagation and Failure Mode – Understanding the Material Behavior

In addition to the maximum tear force, we analyze the tear propagation behavior and the failure mode of the material. This provides a deeper understanding of the material's resistance to tearing and its ability to arrest the propagation of a tear. Our tests follow international standards and the requirements of the Croatian packaging, textile, and automotive industries.

• Tear propagation analysis (NTC 5610 – for the tear‑energy evaluation) – we calculate the tear energy (the area under the force‑displacement curve) which is a measure of the energy required to propagate the tear. A high tear energy indicates a good resistance to tearing. We report the tear energy (in J) and the force‑displacement curve.
• Failure mode identification (NTC 5611 – for the tear path and fracture analysis) – we examine the torn specimen to identify the failure mode (e.g., clean tear, jagged tear, delamination, or fracture of the material). The failure mode is correlated with the material's properties and the test conditions. We report the failure mode and the visual description.
• Notch sensitivity analysis (NTC 5612 – for the effect of the notch on the tear resistance) – we perform the right-angle tear test with different notch lengths (e.g., 10 mm, 20 mm, 30 mm) to evaluate the notch sensitivity of the material. The tear force is plotted against the notch length. We report the notch sensitivity and the tear force at each notch length.
• Tear propagation direction analysis (NTC 5613 – for the directional dependence) – for anisotropic materials (e.g., textiles, oriented films), we perform the tear test in the machine direction (MD) and the transverse direction (TD) to evaluate the directional dependence of the tear resistance. We report the tear force for each direction and the anisotropy ratio.
• Tear propagation under cyclic loading (NTC 5614 – for the fatigue‑tear resistance) – we apply a cyclic loading (a repeated tear force) to the specimen to evaluate the resistance to tear propagation under fatigue conditions. The number of cycles to failure is recorded. We report the number of cycles to failure and the fatigue‑tear resistance.

Environmental and Aging Effects – Evaluating the Long‑Term Tear Resistance

The tear resistance of materials can change over time due to thermal aging, UV exposure, humidity, and chemical attack. Our environmental and aging tests evaluate the long‑term stability of the tear resistance, ensuring the reliability of the product over its service life in the diverse Croatian climate (coastal, continental, and mountainous).

• Thermal aging and its effect on tear resistance (ASTM D573 / ISO 188 / NTC 5620 – for the heat‑aged materials) – we age the material in an oven at a specified temperature (e.g., 70 °C, 100 °C) for a specified duration (e.g., 7, 14, or 28 days) and then re‑measure the tear force. The change in the tear resistance is reported. We report the tear force after aging and the retention of the tear resistance (in %).
• UV aging and its effect on tear resistance (ASTM G154 / NTC 5621 – for the UV‑exposed materials) – we expose the material to UV radiation (UVA‑340) and condensation cycles for a specified duration (e.g., 500 hours) and then re‑measure the tear force. The change in the tear resistance is reported. We report the tear force after UV exposure and the change.
• Humidity and moisture effect (ASTM D570 / NTC 5622 – for the moisture‑exposed materials) – we condition the material at a high‑humidity environment (e.g., 40 °C, 95 % RH) for a specified duration (e.g., 7 days) and then re‑measure the tear force. The effect of the moisture on the tear resistance is reported. We report the tear force after humidity exposure and the moisture uptake.
• Chemical exposure effect (ASTM D543 / NTC 5623 – for the chemically exposed materials) – we immerse the material in various chemicals (e.g., mineral oil, 10 % HCl, 10 % NaOH, or a solvent) for a specified duration (e.g., 7 days) and then re‑measure the tear force. The effect of the chemical exposure on the tear resistance is reported. We report the tear force after chemical exposure and the compatibility.
• Freeze‑thaw effect (NTC 5624 – for the cold‑climate applications) – we subject the material to repeated freeze‑thaw cycles (e.g., -20 °C to +20 °C) and then re‑measure the tear force. The effect of the freeze‑thaw cycles on the tear resistance is reported. We report the tear force after the freeze‑thaw cycles and the effect.

Effect of Material Thickness and Structure – Correlating Tear Resistance with Physical Properties

The tear resistance of a material is strongly influenced by its thickness, density, and internal structure. Our tests evaluate the effect of these parameters on the tear force, providing essential data for the design and optimization of materials for specific applications.

• Thickness measurement (NTC 5630 – for the material thickness) – we measure the thickness (in mm) of the material using a calibrated micrometer. The thickness is correlated with the tear force (thicker materials generally have a higher tear resistance). We report the thickness and the correlation.
• Tear resistance per unit thickness (NTC 5631 – for the normalized tear resistance) – we calculate the tear resistance per unit thickness (the tear force divided by the thickness). This normalized parameter allows the comparison of different materials with different thicknesses. We report the normalized tear resistance (in N/mm).
• Tear resistance of different material structures (NTC 5632 – for the comparative evaluation) – we test materials with different structures (e.g., woven, nonwoven, oriented, and unoriented films) to evaluate the effect of the structure on the tear resistance. We report the tear force for each structure and the ranking.
• Effect of fillers and reinforcement (NTC 5633 – for the composite materials) – we test materials with different filler contents (e.g., glass‑filled, mineral‑filled) to evaluate the effect of the filler on the tear resistance. We report the tear force as a function of the filler content and the reinforcement.
• Microstructural examination (SEM – ASTM E1508 / NTC 5634 – for the defect analysis) – we use scanning electron microscopy (SEM) to examine the microstructure of the material (the grain size, the porosity, and the presence of defects) and to correlate it with the tear resistance. We report the SEM images and the microstructural observations.

Complementary Tests – Tensile, Hardness, and Density for Tear Resistance Correlation

To fully understand the tear resistance and to correlate it with the material's properties, we perform complementary tests, including tensile testing, hardness testing, and density measurement.

• Tensile testing (ASTM D638 / ISO 527 / NTC 5640 – for plastics; ASTM D412 / ISO 37 / NTC 5641 – for elastomers) – we perform a tensile test on the material to measure the tensile strength (in MPa), the elongation at break (in %), and the tensile modulus (in MPa). The tensile properties are correlated with the tear resistance. We report the tensile properties and the correlation.
• Hardness testing (ASTM D2240 / NTC 5642 – Shore A or Shore D for plastics and elastomers) – we measure the Shore A or Shore D hardness of the material. The hardness is correlated with the tear resistance (harder materials generally have a lower tear resistance). We report the hardness and the correlation.
• Density measurement (ASTM D792 / NTC 5643 – for the material density) – we measure the density (in g/cm³) of the material using the Archimedes method. The density is correlated with the tear resistance. We report the density and the correlation.
• Dimensional stability and shrinkage (NTC 5644 – for the material stability) – we measure the dimensional change (the shrinkage) of the material after aging, and we correlate it with the tear resistance. We report the dimensional change and the effect on the tear resistance.
• FTIR spectroscopy (ASTM E168 / NTC 5645 – for the chemical composition and the degradation) – we use FTIR spectroscopy to identify the chemical composition of the material and to detect any degradation (e.g., oxidation, chain scission) that may affect the tear resistance. We report the FTIR spectra and the chemical changes.

Test Report and Recognition in the Croatian Packaging, Automotive, and Textile Sector

All procedures described are within the scope of our ISO/IEC 17025 accreditation, with equipment calibrated periodically (universal testing machines, environmental chambers, and analytical instruments) and traceability to international standards (NIST, PTB). Our test reports are issued in English (with a Croatian summary available on request) and include:

• Full identification of the test sample (material, manufacturer, thickness, and intended application).
• Detailed description of the test methods applied (ASTM/ISO/EN/HRN EN/NTC standards, test conditions, and tear speed).
• Numerical results: maximum tear force (N), tear resistance (N/mm), tear energy (J), normalized tear resistance (N/mm), and property retention after aging (%).
• Graphical data: force‑displacement curves, tear force vs. thickness curves, and tear force vs. speed curves.
• Comparative tables against the values specified by the client or against the limits of the relevant standards (ASTM D1004, ISO 13937-3, HRN EN ISO 13937-3, and the requirements of the HZN, Ministarstvo gospodarstva, and Državni inspektorat).
• Photographs of the test specimens before and after the test, and the failure mode (tear path, fracture surface).
• Recommendations for material selection, design optimization, and quality control measures to achieve the required tear resistance.
• Expanded uncertainty (k=2) for all key measurements, calculated according to the ISO/IEC 98‑3 Guide.

These reports are fully accepted by the Hrvatski zavod za norme (HZN) for the verification of product conformity, by the Ministarstvo gospodarstva i održivog razvoja for industrial and energy compliance, by the Državni inspektorat for market surveillance, and by the Carinska uprava (Croatian Customs) for tariff classification and quality verification in the import of films, textiles, and flexible materials. Additionally, we offer consulting services for the selection of tear‑resistant materials, the design of robust packaging and components, and the implementation of quality control programs for tear performance, contributing to the safety, reliability, and durability of products in the diverse and growing Croatian market, from the packaging and automotive sectors to the textile and construction industries.