Overview
ISO 6237:2017 - Adhesives - Wood-to-wood adhesive bonds - Determination of shear strength by tensile loading specifies a laboratory method to determine the shear strength of wood-to-wood adhesive bonds using standard tensile-loaded specimens. The third edition (2017) covers specimen preparation, conditioning, testing apparatus, test procedure, result expression and reporting. It is intended for adhesives bonding wood-to-wood in parallel-laminated or cross-laminated constructions and is not intended for testing finished manufactured products.
Key Topics and Requirements
- Scope and purpose: Measures shear strength of adhesive bonds with a standard specimen under defined preparation, conditioning and test conditions.
- Specimen types: Two-ply (grain parallel to long axis) and three-ply/cross-laminated constructions (face plies parallel; center ply perpendicular). Dimensions and notch details are specified.
- Apparatus:
- Mixing, spreading and pressing equipment with specified tolerances (e.g., adhesive mix balance ±1 %, spread uniformity ±5 %).
- Test machine capable of ≥5 kN tensile force, accuracy ±2 %, and controlled loading rate.
- Measuring devices: analytical balance, calipers to 0.05 mm.
- Loading and speed: Force applied as a uniformly increasing rate of 2.5 kN/min to 6 kN/min or crosshead speed of 0.5–1.0 mm/min (unless otherwise agreed).
- Conditioning: Panels conditioned at (23 ± 2) °C and (50 ± 5) % RH for 7 days or until constant mass.
- Wood failure assessment: Estimate percentage wood failure using oblique lighting (10°–15°) and report to nearest 10 %.
- Results and statistics: Record force (kN) or stress (kPa) at break; calculate mean and standard deviation per panel and overall.
- Test report requirements: Comprehensive reporting including adhesive ID, timber species and moisture, specimen type/dimensions, conditioning, test speed, number of specimens, individual results, means and standard deviations, and any procedural modifications.
- Annexes: Annex A lists information manufacturers should provide (moisture, spread rate, pressing conditions); Annex B addresses timber species, thickness, surfaces, quality and moisture content.
Applications and Users
Who uses ISO 6237:2017:
- Adhesive manufacturers - product development and quality control.
- Timber and panel producers - comparative evaluation of bonding performance for plywood, laminated timber and other wood assemblies.
- Independent test laboratories - standardized bond strength testing and certification.
- R&D teams and QA/QC departments - validating formulations, process conditions and supplier verification.
Practical uses:
- Benchmarking adhesive bond performance.
- Establishing process parameters (spread rate, press conditions, conditioning).
- Supporting product specifications and technical datasheets.
Related Standards
- ISO 472 - Plastics - Vocabulary (terms and definitions referenced by ISO 6237)
- ISO/IEC Directives referenced for editorial and standards development practices
Keywords: ISO 6237:2017, wood-to-wood adhesive bonds, shear strength, tensile loading, adhesive testing, bond strength, specimen preparation, conditioning, test report.
