Plastics - Determination of tensile properties - Part 4: Test conditions for isotropic and orthotropic fibre-reinforced plastic composites (ISO 527-4:2021, Corrected version 2022-02)

This document specifies the test conditions for the determination of the tensile properties of isotropic and orthotropic fibre-reinforced plastic composites, based upon the general principles given in ISO 527-1. NOTE 1   Unidirectional reinforced materials are covered by ISO 527-5. The methods are used to investigate the tensile behaviour of the test specimens and for determining the tensile strength, tensile modulus, Poisson's ratios and other aspects of the tensile stress-strain relationship under the defined conditions. The test method is suitable for use with the following materials: —    fibre-reinforced thermosetting and thermoplastic composites incorporating non-unidirectional reinforcements such as mats, woven fabrics, woven rovings, chopped strands, combinations of such reinforcements, hybrids, rovings, short or milled fibres or preimpregnated materials (prepregs); NOTE 2   Injection moulded specimens are covered by ISO 527-2. —    combinations of the above with unidirectional reinforcements and multidirectional reinforced materials constructed from unidirectional layers, provided such laminates are symmetrical; NOTE 3   Materials with completely or mainly unidirectional reinforcements are covered by ISO 527-5. —    finished products made from materials mentioned above. The reinforcement fibres covered include glass fibres, carbon fibres, aramid fibres and other similar fibres.