ISO 4606:1995

Overview

ISO 4606:1995 - "Textile glass - Woven fabric - Determination of tensile breaking force and elongation at break by the strip method" - specifies a standardized laboratory method to measure the tensile breaking force and elongation at break of frayed strips of woven textile glass. This second edition (1995) cancels ISO 4606:1979. The method applies to unimpregnated glass fabrics and those impregnated with sizing or stiffening agents, but excludes fabrics coated with rubber or plastics. Tests are performed on specimens conditioned in a standard atmosphere.

Key topics and technical requirements

• Specimen types: Two test specimen types are defined:
  • Type I (stiff fabrics) - specimen length 350 mm, gauge length 200 mm; template/strip width before unravelling typically 65 mm, unraveled width 50 mm.
  • Type II (pliable fabrics) - specimen length 250 mm, gauge length 100 mm; template/strip width before unravelling typically 40 mm, unraveled width 25 mm.
• Specimen preparation: Ends are bonded to backing (bonded tabs) and edges are frayed to produce specified unraveled widths; adhesives and impregnation methods for end-tabs are described.
• Conditioning and atmosphere: Condition specimens for 16 hours (or agreed time) in a standard laboratory atmosphere per ISO 139 / ISO 291; test in the same atmosphere.
• Test machine and settings:
  • Reference method: constant-rate-of-extension (CRE) machine.
  • Required extension rates: 100 mm/min for Type I and 50 mm/min for Type II (with allowed tolerances).
  • Clamps must hold the specimen without slippage or damage; clamp faces wider than the unraveled specimen and flat/parallel.
  • Instrument accuracy: force indication within 1% and extension within 1% (as specified).
• Measurements and reporting:
  • Record breaking force (maximum) and elongation at break.
  • Report arithmetic mean for warp and weft directions (breaking force in newtons to two decimals; elongation as percent to two significant figures).
  • Reject results when rupture initiates within 10 mm of clamps; record number of rejected specimens.

Applications and users

ISO 4606 is used by:

• Manufacturers of textile glass (glass cloth, rovings) for quality control and acceptance testing.
• Composite fabricators and laminators specifying reinforcement performance.
• Materials testing laboratories and R&D teams assessing tensile properties of woven glass fabrics.
• Procurement and standards compliance teams requiring traceable test data for design or certification.

Practical uses include material specification, incoming inspection, production control, and data for engineering calculations of reinforced composites.

Related standards

• ISO 1421:1977 - Fabrics coated with rubber or plastics (related exclusion).
• ISO 5081:1977 and ISO 5082:1982 - Textile strip and grab methods for breaking strength and elongation.
• ISO 139 / ISO 291 - Standard atmospheres for conditioning and testing.

Keywords: ISO 4606, textile glass, woven fabric, strip method, tensile breaking force, elongation at break, gauge length, tensile-testing machine.