ISO 17590:2025

Fine ceramics (advanced ceramics, advanced technical ceramics) - Methods of tests for reinforcements - Determination of the tensile properties of ceramic filaments at elevated temperature in air using the hot grip technique

This document specifies a test method for determination of tensile properties, such as tensile strength, Young’s modulus, and fracture strain of ceramic filaments at elevated temperature in air using the hot grip technique. This document applies to continuous ceramic filaments obtained either from a multifilament bundle or spool. This document does not apply to ceramic filaments with creep behaviour at test temperature. The hot grip technique is limited by the temperature resistance of the current ceramic adhesive.

Céramiques techniques — Méthodes d'essais pour renforts — Détermination des propriétés en traction des filaments à température élevée par la technique des mors chauds

General Information

• Status: Published
• Publication Date: 01-Jul-2025
• ICS: 81.060.30 - Advanced ceramics
• Technical Committee: ISO/TC 206 - Fine ceramics
• Drafting Committee: ISO/TC 206 - Fine ceramics
• Current Stage: 6060 - International Standard published
• Start Date: 02-Jul-2025
• Due Date: 13-Jul-2025
• Completion Date: 02-Jul-2025

Overview

ISO 17590:2025 specifies a standardized test method for determining the tensile properties of continuous ceramic filaments at elevated temperatures in air using the hot grip technique. The standard targets advanced or fine ceramics (advanced technical ceramics) and defines procedures to measure tensile strength, Young’s modulus, and fracture strain of filaments obtained from multifilament bundles or spools. It excludes filaments that exhibit creep at the test temperature and notes that the hot grip technique is limited by the temperature resistance of the adhesive used.

Key topics and technical requirements

• Test principle: Filament ends are bonded into ceramic tubes (hot grips) with high-temperature adhesive, heated in a furnace in air, and loaded under constant displacement until failure. Force and displacement are recorded.
• Specimen preparation:
  • Use continuous ceramic filaments from bundle or spool.
  • Recommended alumina ceramic tubes (typical inner diameter 1–1.5 mm; outer diameter 2.5–3.5 mm) and an oblique cut to facilitate gluing.
  • Define gauge length (L0) and measure initial cross‑section area (S0) at room temperature.
• Apparatus and instrumentation:
  • Tensile testing machine with constant cross‑head displacement and force-measuring system compliant with ISO 7500‑1 (class 1 or better).
  • Cross-head displacement measurement accuracy better than 1 μm.
  • Thermocouples per IEC 60584‑1; furnace temperature resolution ≥1 °C and accuracy ≤5 °C.
  • Furnace heating rate capability 30–100 °C/min and specified temperature uniformity within the gauge length (<10 °C when <300 °C; <20 °C at ≥300 °C).
• Adhesive: Must remain bonded at test temperature and not soften to prevent slippage.
• Calculations & definitions:
  • Tensile strength (σm) = Fm / S0
  • Young’s modulus derived from gauge length, initial area, total compliance (Ct), and load train compliance (Cl).
  • Definitions for maximum tensile force (Fm), total compliance, and fracture strain (εm) are provided.

Applications

• Characterizing high‑temperature mechanical behavior of ceramic filaments used in:
  • Ceramic matrix composites (CMCs)
  • High‑temperature structural reinforcements
  • Aerospace, energy, and industrial components where elevated‑temperature strength and stiffness are critical
• Supporting material selection, quality control, R&D, and supplier verification for advanced ceramic reinforcements.

Who should use ISO 17590:2025

• Materials scientists and engineers testing ceramic filaments
• Accredited testing laboratories (ISO/IEC 17025 conformity)
• Ceramic filament and composite manufacturers
• Product qualification and quality assurance teams

Related standards

• ISO 7500‑1 (tensile machine calibration)
• ISO 11567 (filament diameter and area)
• ISO 19634 (ceramic composite notations)
• ISO/IEC 17025 (laboratory competence)
• IEC 60584‑1 (thermocouples)

Keywords: ISO 17590:2025, fine ceramics, ceramic filaments, hot grip technique, tensile strength, Young’s modulus, elevated temperature testing.

Standards Content (Sample)

International
Standard
ISO 17590
First edition
Fine ceramics (advanced ceramics,
2025-07
advanced technical ceramics) —
Methods of tests for reinforcements
— Determination of the tensile
properties of ceramic filaments at
elevated temperature in air using
the hot grip technique
Céramiques techniques — Méthodes d'essais pour renforts
— Détermination des propriétés en traction des filaments à
température élevée par la technique des mors chauds
Reference number
© ISO 2025
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
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or ISO’s member body in the country of the requester.
ISO copyright office
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Published in Switzerland
ii
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Apparatus . 3
5.1 Tensile testing machine .3
5.2 Grip system .3
5.3 Specimen holding device .3
5.4 Adhesive .4
5.5 Thermocouples .4
5.6 Heating device .4
6 Test specimen gauge length . 5
7 Test specimen preparation . 5
7.1 Size removal .5
7.2 Test specimen assembly .5
7.3 Filament selection . .6
7.4 Filament gluing . .7
7.5 Filament initial cross-section area determination.7
7.6 Number of test specimens .7
8 Test procedure . 7
8.1 Load cell .7
8.2 Specimen mounting . .7
8.3 Specimen adjusting .7
8.4 Furnace heating .7
8.5 Displacement rate setting .8
8.6 Measurement .8
8.7 Test validity .8
9 Calculation of results . 8
9.1 Tensile strength .8
9.2 Total compliance .8
9.3 Load train compliance .9
9.4 Young’s modulus.10
9.5 Fracture strain .10
10 Test report .11
Bibliography .12

iii
Foreword
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This document was prepared by Technical Committee ISO/TC 206, Fine Ceramics.
Any feedback or questions on this document should be directed to the user’s national standards body. A
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iv
International Standard ISO 17590:2025(en)
Fine ceramics (advanced ceramics, advanced technical
ceramics) — Methods of tests for reinforcements —
Determination of the tensile properties of ceramic filaments
at elevated temperature in air using the hot grip technique
1 Scope
This document specifies a test method for determination of tensile properties, such as tensile strength,
Young’s modulus, and fracture strain of ceramic filaments at elevated temperature in air using the hot grip
technique. This document applies to continuous ceramic filaments obtained either from a multifilament
bundle or spool. This document does not apply to ceramic filaments with creep behaviour at test temperature.
The hot grip technique is limited by the temperature resistance of the current ceramic adhesive.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 7500-1, Metallic materials — Calibration and verification of static uniaxial testing machines — Part 1:
Tension/compression testing machines — Calibration and verification of the force-measuring system
ISO 10548, Carbon fibre — Determination of size content
ISO 11567, Carbon fibre — Determination of filament diameter and cross-sectional area
ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories
ISO 19634, Fine ceramics (advanced ceramics, advanced technical ceramics) — Ceramic composites — Notations
and symbols
IEC 60584-1, Thermocouples — Part 1: EMF specifications and tolerances
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 19634 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
gauge length
L
initial inner distance between tubular grips glued to fibre ends at room temperature

3.2
initial cross-section area
S
initial area of the cross section of the filament within the gauge length (3.1) determined at room temperature
[SOURCE: ISO 19630:2017, 3.3, modified — “determined at room temperature” added to definition.]
3.3
maximum tensile force
F
m
highest recorded tensile force on the test specimen when tested to failure
[SOURCE: ISO 19630:2017, 3.4.]
3.4
tensile strength
σ
m
ratio of the maximum tensile force (3.4) to the initial cross-section area (3.2)
[SOURCE: ISO 19630:2017, 3.6]
3.5
total compliance
C
t
inverse of the slope in the linear part of the force/displacement curve
[SOURCE: ISO 19630:2017, 3.8]
3.6
load train compliance
C
l
ratio of the displacement, excluding any test specimen contribution, to the corresponding force during the
tensile test
[SOURCE: ISO 19630:2017, 3.9]
3.7
strain
ε
ratio of the longitudinal deformation to the gauge length (3.1)
[SOURCE: ISO 19630:2017, 3.10]
3.8
fracture strain
ε
m
strain at failure of the test specimen
[SOURCE: ISO 19630:2017, 3.11]
3.9
elastic modulus
E
slope of the linear part of the tensile stress-strain curve
[SOURCE: ISO 19630:2017, 3.12]
4 Principle
For the hot-grip technique, the ends of a ceramic filament are bonded to two ceramic tubes by using adhesive
with high temperature resistance. The ceramic filament specimen is heated to the test temperature in air

and loaded in tension at a constant displacement rate by a suitable mechanical testing machine until failure.
[5]-[9]
The tensile force and cross-head displacement are measured and recorded.
[1]-[4]
The tensile strength is calculated from the force (F ) and the initial cross-section area (S ).
m 0
The Young’s modulus is calculated from the ga
...