ISO 13586-2018 PDF

Full title and description

ISO 13586:2018 — Plastics — Determination of fracture toughness (GIC and KIC) — Linear elastic fracture mechanics (LEFM) approach. This international standard specifies test methods and principles for measuring mode I fracture toughness of plastics using cracked specimens (three-point-bending and compact-tension/compact-specimen tensile geometries), and gives requirements, validity criteria and guidance for testing a range of rigid and semi-rigid thermoplastic and thermosetting materials (including guidance for short-fibre compounds).

Abstract

This document defines two test methods for determining fracture toughness in mode I (GIC and KIC) for plastics under controlled linear-elastic conditions. It covers specimen types, pre-cracking, test procedures, calculation of fracture parameters, restrictions to ensure plane-strain/linear-elastic conditions, precision and test-report requirements, and includes annexes with calibration factors and guidance for short-fibre reinforced plastics.

General information

• Status: Published (current edition confirmed).
• Publication date: July 2018 (published 25 July 2018 / edition 2, 2018).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 83.080.01 (Plastics — general). (Some national listings may include additional local classifications.)
• Edition / version: Edition 2 (2018).
• Number of pages: 22 pages (ISO published text; national/adopted versions may report additional pages including national forewords).

Scope

Specifies principles and procedures for determining fracture toughness of plastics in crack-opening mode (mode I) using linear-elastic fracture mechanics (LEFM). Two geometries are described — three-point-bending (often single-edge-notch bending variants) and compact-specimen tensile/compact-tension — with requirements for specimen preparation, pre-cracking, data acquisition and calculation of GIc and KIc. The standard sets validity criteria (linearity of load–displacement response, minimum specimen width/thickness to approach plane-strain, and crack sharpness) and provides annexes for calibration factors and guidance on testing injection-moulded plastics containing short discontinuous fibres.

Key topics and requirements

• Definitions and terms related to fracture toughness (GIC, KIC, plane-strain conditions).
• Specification of specimen types and dimensions for three-point-bend and compact-tension tests.
• Pre-cracking procedures and crack-sharpness requirements to ensure representative toughness values.
• Test procedure: loading rate, instrumentation and measurement of load–displacement for LEFM analysis.
• Calculation methods for energy release rate (GIC) and stress intensity factor (KIC) with required formulas and correction/calibration factors (Annex A).
• Validity and acceptance criteria (linearity limits, specimen geometry/thickness to approximate plane-strain, and reporting requirements).
• Guidance for materials containing short discontinuous fibres and related limitations (informative Annex B).
• Precision, repeatability considerations and required content for test reports.

Typical use and users

Used by materials testing laboratories, R&D and product development teams, quality-control and certification bodies, and materials engineers in industries that specify or validate fracture performance of plastics (automotive, aerospace, consumer goods, electrical/electronic housings, and polymer compound suppliers). The standard is applied when fracture-toughness parameters (GIc, KIc) are needed for material selection, design input, failure investigation or comparative testing.

Related standards

ISO 13586:2018 replaces ISO 13586:2000 (withdrawn). Related test standards include ASTM D5045 (Standard Test Methods for Plane‑Strain Fracture Toughness and Strain Energy Release Rate of Plastic Materials), and other ISO mechanical-property standards commonly used alongside fracture testing such as ISO 527 (tensile properties) and ISO 178 (flexural properties). These documents are complementary for a complete mechanical-characterization program for plastics.

Keywords

fracture toughness, GIC, KIC, LEFM, plastics, fracture mechanics, compact tension, three-point bending, pre-cracking, plane-strain, calibration factors, short-fibre plastics.

FAQ

Q: What is this standard?

A: ISO 13586:2018 is an international standard that specifies laboratory methods and requirements for determining mode I fracture toughness (GIC and KIC) of plastics using linear elastic fracture mechanics test procedures.

Q: What does it cover?

A: It covers specimen geometries (three-point-bending and compact-tension types), specimen preparation and pre-cracking, test execution, calculation of GIc and KIc, validity criteria to ensure linear-elastic/plane-strain conditions, calibration factors and guidance for short-fibre reinforced plastics.

Q: Who typically uses it?

A: Materials test laboratories, quality and R&D engineers, manufacturers and certification bodies that need quantified fracture-toughness data for plastics used in design, failure analysis or specification.

Q: Is it current or superseded?

A: ISO 13586:2018 is the current (second) edition published in July 2018; it replaced the 2000 edition. The ISO record shows this edition as published and confirmed (reviewed) in subsequent five-year reviews. Users should check their national adopters for any national amendments or adoption nuances.

Q: Is it part of a series?

A: It is a standalone ISO test method focused on fracture toughness, but it is commonly used with other ISO plastics testing standards (for example ISO 527 for tensile properties and ISO 178 for flexural properties) to build a comprehensive material characterization dataset.

Q: What are the key keywords?

A: fracture toughness, GIC, KIC, LEFM, plastics testing, compact tension, three-point bending, plane-strain, pre-cracking, calibration factors.