Abstract

This document outlines methods for measuring the strain distribution for randomly oriented chopped strand- or fibre-reinforced plastic composites, based upon the general principles given in ISO 527-4. The methods are used to statistically evaluate the inherent variation of strain-based properties. The main purpose of this document compared to existing standards is to evaluate the strain distribution due to the random orientation of chopped fibres, while ISO 527-4 is sufficient for evaluating only the bulk elastic modulus. This standard provides two methods for evaluating an inherent strain distribution of the material, Method A as using DIC analysis system and Method B as using several strain gauges with a short gauge length. The methods are suitable for use with fibre-reinforced thermosetting and thermoplastic composites incorporating discontinuous or chopped reinforcements such as mats, chopped strands or tapes, long-fibre injection or combination of such reinforcements. The methods are not normally suitable for continuous fibre-reinforced materials which generate homogeneous strain distribution on the surface of the test specimen.

Begin

2025-01-27

WI

00249A79

Planned document number

DIN EN ISO 527-6

Project number

05402387

Responsible national committee

NA 054-02-02 AA - Reinforced plastics and thermosetting materials  

Responsible european committee

CEN/TC 249 - Plastics  

Responsible international committee

ISO/TC 61/SC 13/WG 2 - Laminates and moulding compounds