ISO 527-1:2019 pdf download – Plastics — Determination of tensile properties — Part 1: General principles.
1 Scope 1.1 This document specifies the general principles for determining the tensile properties of plastics and plastic composites under defined conditions. Several different types of test specimen are defined to suit different types of material which are detailed in subsequent parts of ISO 527. 1.2 The methods are used to investigate the tensile behaviour of the test specimens and for determining the tensile strength, tensile modulus and other aspects of the tensile stress/strain relationship under the conditions defined. 1.3 The methods are selectively suitable for use with the following materials: — rigid and semi-rigid moulding, extrusion and cast thermoplastic materials, including filled and reinforced compounds in addition to unfilled types; rigid and semi-rigid thermoplastics sheets and films; — rigid and semi-rigid thermosetting moulding materials, including filled and reinforced compounds; rigid and semi-rigid thermosetting sheets, including laminates; — fibre-reinforced thermosets and thermoplastic composites incorporating unidirectional or non- unidirectional reinforcements, such as mat, woven fabrics, woven rovings, chopped strands, combination and hybrid reinforcement, rovings and milled fibres; sheet made from pre-impregnated materials (prepregs); — thermotropic liquid crystal polymers. The methods are not normally suitable for use with rigid cellular materials, for which ISO 1926 is used, or for sandwich structures containing cellular materials.
5.1.5.1 Extensometers Contact extensometers shall comply with ISO 9513, class 1. The accuracy of this class shall be attained in the strain range over which measurements are being made. Non-contact extensometers may also be used, provided they meet the same accuracy requirements. The extensometer shall be capable of determining the change in the gauge length of the test specimen at any time during the test. It is desirable, but not essential, that the instrument should record this change automatically. The instrument shall be essentially free of inertia lag at the specified speed of testing. For the determination of tensile modulus, the instrument shall be capable of measuring the change in the gauge length of the specimen with an accuracy of 1 % of the relevant value or better for all gauge lengths of 50 mm or higher, corresponding to a requirement of absolute accuracy of ±1 μm for a gauge length of 50 mm and to ±1,5 μm, in case a gauge length of 75 mm is used. For smaller gauge lengths between 20 mm and 50 mm an absolute accuracy of ±1 μm is sufficient (see Figure 2 and Annex C.)