ISO 3342:2011

Overview - ISO 3342:2011 (Textile glass mats - Tensile breaking force)

ISO 3342:2011 specifies a standardized laboratory method to determine the tensile breaking force of textile glass mats. The procedure is primarily intended for chopped‑strand mats and is also applicable to certain continuous‑strand mats (typically those used for pultrusion). The standard describes specimen preparation, conditioning, tensile‑testing machine requirements, test procedure, calculation of results and reporting details.

Key topics and technical requirements

• Scope: Determination of maximum force required to break a mat specimen in a tensile test (expressed in newtons).
• Specimen dimensions:
  • Chopped‑strand mat: template 150 mm × 316 mm (major axis parallel to mat longitudinal direction).
  • Continuous‑strand mat (pultrusion): template 75 mm × 316 mm (longitudinal specimens only).
• Tensile‑testing machine:
  • Clamps: 160 mm wide, minimum 25 mm depth; faces plane and parallel; initial clamp separation 200 mm.
  • Recording mechanism with accuracy within ±1% of true force; length error ≤ 2 mm.
  • Reference machine: constant rate of extension. Other machine types may be used by agreement.
• Test speed and setup:
  • Rate of clamp separation: 200 mm/min ± 10 mm/min.
  • Free specimen length: 200 mm; align specimen axis with machine axis.
  • Discard results if specimen breaks within 10 mm of clamp or slips.
• Conditioning and atmosphere:
  • Use ISO 291 standard laboratory atmospheres.
  • Conditioning: 16 h for an elementary unit; 1 h for test specimens/laboratory samples.
• Number of specimens: Default determination based on five specimens or more.
• Results: Report mean tensile breaking force (rounded to nearest 1 N); note non‑clean breaks. Precision statement: not available (no interlaboratory data at publication).

Practical applications and users

ISO 3342:2011 is used by:

• Manufacturers of glass‑reinforcement mats for quality control and specification verification.
• Composite fabricators and pultrusion producers assessing reinforcement strength.
• Materials testing laboratories performing contract or compliance testing.
• R&D teams comparing mat constructions or processing effects (e.g., roll winding vs. pre‑winding differences).

Benefits:

• Provides repeatable test procedure for procurement/specification acceptance.
• Helps ensure consistent mechanical performance of reinforcement mats used in composites.

Related standards

• ISO 291 - Plastics: standard atmospheres for conditioning and testing (referenced for conditioning/test environment).
• ISO 3374 - Reinforcement products: determination of mass per unit area (useful when specimens are taken from mass-per-area tests).

Keywords: ISO 3342:2011, textile glass mats, tensile breaking force, chopped‑strand mat, pultrusion, tensile testing, conditioning, ISO 291, specimen preparation, material testing.