EN ISO 527-4:2023 PDF

Overview

EN ISO 527-4:2023 (ISO 527-4:2023) specifies test conditions for determining the tensile properties of isotropic and orthotropic fibre‑reinforced plastic composites, based on the general principles in ISO 527-1. It is applicable to non‑unidirectional reinforced composites (mats, woven fabrics, woven rovings, chopped strands, hybrids, prepregs, short/milled fibres), symmetrical laminates that combine unidirectional layers, and finished products. Reinforcement fibres include glass, carbon, aramid and similar fibres. Note: unidirectional materials are covered by ISO 527-5; injection‑moulded specimens by ISO 527-2.

Key topics and requirements

• Test objective: determine tensile strength, tensile modulus, Poisson’s ratios and full tensile stress–strain behaviour under defined test conditions.
• Specimen types: includes traditional geometries and a new type 4 tapered specimen designed to be tested without end tabs (introduced to improve testing of thermoplastic‑matrix materials).
• Specimen preparation and dimensions: requirements for shape, preparation, end tabs (for type 3), gauge marks, alignment checks and anisotropy considerations.
• Apparatus and gripping: guidance on test machines, grip design, grip faces and unbonded tab / fine‑grip options (Annexes cover grip configurations and tab use).
• Measurement and instrumentation: use and placement of extensometers, strain gauges and gauge marks for accurate modulus and Poisson’s ratio measurements.
• Test conditions and procedure: conditioning, test atmosphere, clamping, prestress control, testing speeds (differentiated for specimen types such as type 1B vs types 2–4), data recording and failure location criteria.
• Calculations and reporting: methods for calculating properties for parallel‑sided specimens and failure‑location related strength calculations (Annex E), plus precision and required test report content.
• Supporting annexes: alignment, tapered geometry details, gripping alternatives, specimen preparation norms.

Practical applications and users

EN ISO 527-4:2023 is intended for:

• Composite material manufacturers for material characterization and specification.
• Test laboratories and quality‑control departments performing routine tensile testing and batch verification.
• R&D and design engineers needing reliable tensile modulus, strength and Poisson’s ratio data for structural analysis and simulation.
• Certification bodies and procurement teams verifying supplier claims or performing product qualification.
• Failure analysis teams assessing tensile failure modes and material performance.

Typical uses include generating design allowables, comparing materials or suppliers, validating processing changes (e.g., thermoplastic vs thermoset behavior), and providing traceable test data for product compliance.

Related standards

• ISO 527-1 - general principles for tensile testing of plastics
• ISO 527-2 - injection‑moulded specimens
• ISO 527-5 - unidirectional reinforced materials
• EN ISO 527-4:2023 - official CEN endorsement of ISO 527-4:2023

Keywords: tensile properties, fibre‑reinforced plastic composites, tensile test, ISO 527-4, EN ISO 527-4:2023, tensile strength, tensile modulus, Poisson’s ratio, composite testing.