SIST EN ISO 14544:2016

SLOVENSKI STANDARD
kSIST FprEN ISO 14544:2015
01-november-2015
)LQDNHUDPLNDVRGREQDNHUDPLNDVRGREQDWHKQLþQDNHUDPLND0HKDQVNH
ODVWQRVWLNHUDPLþQLKNRPSR]LWRYSULYLVRNLWHPSHUDWXUL8JRWDYOMDQMHODVWQRVWLSUL
VWLVNDQMX,62
Fine ceramics (advanced ceramics, advanced technical ceramics) - Mechanical
properties of ceramic composites at high temperature - Determination of compression
properties (ISO 14544:2013)
Hochleistungskeramik - Mechanische Eigenschaften von keramischen
Verbundwerkstoffen bei hoher Temperatur - Bestimmung der Eigenschaften unter Druck
(ISO 14544:2013)
Céramiques techniques - Propriétés mécaniques des céramiques composites à haute
température - Détermination des caractéristiques en compression (ISO 14544:2013)
Ta slovenski standard je istoveten z: FprEN ISO 14544 rev
ICS:
81.060.30 Sodobna keramika Advanced ceramics
kSIST FprEN ISO 14544:2015 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

kSIST FprEN ISO 14544:2015

---------------------- Page: 2 ----------------------

kSIST FprEN ISO 14544:2015

EUROPEAN STANDARD
FINAL DRAFT
FprEN ISO 14544 rev
NORME EUROPÉENNE

EUROPÄISCHE NORM

September 2015
ICS 81.060.30 Will supersede EN 12290:2005, EN 12291:2003
English Version
Fine ceramics (advanced ceramics, advanced technical
ceramics) - Mechanical properties of ceramic composites at high
temperature - Determination of compression properties (ISO
14544:2013)
Céramiques techniques - Propriétés mécaniques des Hochleistungskeramik - Mechanische Eigenschaften von
céramiques composites à haute température - keramischen Verbundwerkstoffen bei hoher Temperatur -
Détermination des caractéristiques en compression (ISO Bestimmung der Eigenschaften unter Druck (ISO
14544:2013) 14544:2013)
This draft European Standard is submitted to CEN members for unique acceptance procedure. It has been drawn up by the Technical
Committee CEN/TC 184.

If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations which
stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other language
made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.


EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2015 CEN All rights of exploitation in any form and by any means reserved Ref. No. FprEN ISO 14544 rev:2015 E
worldwide for CEN national Members.

---------------------- Page: 3 ----------------------

kSIST FprEN ISO 14544:2015
FprEN ISO 14544:2015 (E)
Contents Page
European foreword .3

2

---------------------- Page: 4 ----------------------

kSIST FprEN ISO 14544:2015
FprEN ISO 14544:2015 (E)
European foreword
The text of ISO 14544:2013 has been prepared by Technical Committee ISO/TC 206 “Fine ceramics” of the
International Organization for Standardization (ISO) and has been taken over as FprEN ISO 14544:2015 by
Technical Committee CEN/TC 184 “Advanced technical ceramics” the secretariat of which is held by DIN.
This document is currently submitted to the Unique Acceptance Procedure.
This document will supersede EN 12291:2003, EN 12290:2005.
Endorsement notice
The text of ISO 14544:2013 has been approved by CEN as FprEN ISO 14544:2015 without any modification.
3

---------------------- Page: 5 ----------------------

kSIST FprEN ISO 14544:2015

---------------------- Page: 6 ----------------------

kSIST FprEN ISO 14544:2015
INTERNATIONAL ISO
STANDARD 14544
First edition
2013-07-01
Fine ceramics (advanced ceramics,
advanced technical ceramics) —
Mechanical properties of ceramic
composites at high temperature —
Determination of compression
properties
Céramiques techniques — Propriétés mécaniques des céramiques
composites à haute température — Détermination des
caractéristiques en compression
Reference number
ISO 14544:2013(E)
©
ISO 2013

---------------------- Page: 7 ----------------------

kSIST FprEN ISO 14544:2015
ISO 14544:2013(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2013
All rights reserved. Unless otherwise specified, 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 the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2013 – All rights reserved

---------------------- Page: 8 ----------------------

kSIST FprEN ISO 14544:2015
ISO 14544:2013(E)

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 3
5 Apparatus . 4
5.1 Test machine . 4
5.2 Load train. 4
5.3 Gastight test chamber . 4
5.4 Set-up for heating . 5
5.5 Extensometer . 5
5.6 Temperature measurement . 5
5.7 Data recording system . 5
5.8 Micrometers . 6
6 Test specimens. 6
6.1 General . 6
6.2 Compression between platens . 6
6.3 Test specimen used with grips . 7
7 Test specimen preparation .10
7.1 Machining and preparation .10
7.2 Number of test specimens .10
8 Test procedures .11
8.1 Test set-up: temperature considerations .11
8.2 Test set-up: other considerations .11
8.3 Testing technique .12
8.4 Test validity .13
9 Calculation of results .13
9.1 Test specimen origin .13
9.2 Compression strength .13
9.3 Strain at maximum compression force .14
9.4 Proportionality ratio or pseudo-elastic modulus, elastic modulus .14
10 Test report .16
Annex A (normative) Buckling: How to proceed when buckling is suspected .17
Bibliography .18
© ISO 2013 – All rights reserved iii

---------------------- Page: 9 ----------------------

kSIST FprEN ISO 14544:2015
ISO 14544:2013(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2. www.iso.org/directives
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any
patent rights identified during the development of the document will be in the Introduction and/or on
the ISO list of patent declarations received. www.iso.org/patents
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
The committee responsible for this document is ISO/TC 206, Fine ceramics.
iv © ISO 2013 – All rights reserved

---------------------- Page: 10 ----------------------

kSIST FprEN ISO 14544:2015
INTERNATIONAL STANDARD ISO 14544:2013(E)
Fine ceramics (advanced ceramics, advanced technical
ceramics) — Mechanical properties of ceramic
composites at high temperature — Determination of
compression properties
1 Scope
This International Standard specifies the conditions for determination of compression properties of
ceramic matrix composite materials with continuous fibre reinforcement for temperatures up to 2 000 °C.
This International Standard applies to all ceramic matrix composites with a continuous fibre
reinforcement, unidirectional (1D), bidirectional (2D), and tridirectional (xD, with 2 < x ≤ 3), loaded
along one principal axis of reinforcement.
Two types of compression are distinguished:
a) compression between platens;
b) compression using grips.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 3611, Geometrical product specifications (GPS) — Dimensional measuring equipment: Micrometers for
external measurements — Design and metrological characteristics
ISO 7500-1, Metallic materials — Verification of static uniaxial testing machines — Part 1: Tension/compression
testing machines — Verification and calibration of the force-measuring system
EN 10002-4, Metallic materials — Tensile test — Part 4: Verification of extensometers used in uniaxial testing
CEN/TS 15867:2009, Advanced technical ceramics — Ceramic composites — Guide to the determination of
the degree of misalignment in unixial mechanical tests
IEC 60584-1:1995, Thermocouples — Part 1: Reference tables
IEC 60584-2:1982, Thermocouples — Part 2: Tolerances
IEC 60584-2:1982,Amendment 1:1989
3 Terms a nd definiti ons
For the purposes of this document, the following terms and definitions apply.
3.1
test temperature
T
temperature of the test piece at the centre of the gauge length
© ISO 2013 – All rights reserved 1

---------------------- Page: 11 ----------------------

kSIST FprEN ISO 14544:2015
ISO 14544:2013(E)

3.2
calibrated length
l
part of the test specimen that has uniform and minimum cross-section area
3.3
gauge length
L
o
initial distance between reference points on the test specimen in the calibrated length
3.4
controlled-temperature zone
part of the calibrated length, including the gauge length, where the temperature is within a range of
50 °C of the test temperature
3.5
initial cross-section area
A
o
initial cross-section area of the test specimen within the calibrated length, at test temperature
Note 1 to entry: Two initial cross-section areas of the test specimen can be defined as follows.
3.5.1
apparent cross-section area
total area of the cross section, A
o,a
3.5.2
effective cross-section area
total area corrected by a factor, to account for the presence of an antioxidant protection, A
o,e
3.6
longitudinal deformation
ΔL
decrease in the gauge length L between reference points under a compression force
3.7
compression strain
ε
relative change in the gauge length defined as the ratio ΔL/L
o
Note 1 to entry: Its value corresponding to the maximum force shall be denoted as ε .
c,m
3.8
compression stress
σ
compression force supported by the test specimen at any time in the test divided by the initial cross-
section area (A )
o
Note 1 to entry: Two compression stresses can be distinguished:
— apparent compression stress, σ , when the apparent cross-section area (or total cross-section area) is used;
a
— effective compression stress, σ , when the effective cross-section area is used
e
3.9
maximum compression force
F
m
highest recorded compression force in a compression test on the test specimen when tested to failure
2 © ISO 2013 – All rights reserved

---------------------- Page: 12 ----------------------

kSIST FprEN ISO 14544:2015
ISO 14544:2013(E)

3.10
compression strength
σ
c,m
ratio of the maximum compression force (F ) to the initial cross-section area (A )
m o
Note 1 to entry: Two compression strengths can be distinguished:
— apparent compression strength, σ , when the apparent cross-section area (or total cross-section area) is used;
c,m,a
— effective compression strength, σ , when the effective cross-section area is used.
c,m,e
3.11
proportionality ratio or pseudo-elastic modulus, E
p
slope of the linear section of the stress-strain curve, if any
Note 1 to entry: Examination of the stress-strain curves for ceramic matrix composites allows definition of the
following cases:
a)  Material with a linear section in the stress-strain curve.
For ceramic matrix composites that have a mechanical behaviour characterized by a linear section, the
proportionality ratio is defined as:
σσ−
21
Ep(σσ,)= (1)
12
εε−
22
where (ε , σ ) and (ε , σ ) lie near the lower and upper limits of the linear section of the stress-strain curve.
1 1 2 2
The proportionality ratio or pseudo-elastic modulus is termed the elastic modulus, E, in the single case where the
material has a linear behaviour from the origin.
b)  Material with no-linear section in the stress-strain curve.
In this case only stress-strain couples can be fixed.
Two proportionality ratios or pseudo-elastic moduli can be distinguished:
— apparent proportionality ratio, Ep , when the apparent compression stress is used;
a
— effective proportionality ratio, Ep , when the effective compression stress is used.
e
4 Principle
A test specimen of specified dimensions is heated to the test temperature, and loaded in compression.
The test is performed at constant crosshead displacement rate, or constant deformation rate. Force and
longitudinal deformation are measured and recorded simultaneously.
NOTE 1 The test duration is limited to reduce creep effects.
NOTE 2 Constant loading rate is only allowed in the case of linear stress-strain behaviour up to failure.
NOTE 3 In order to protect fixtures, it is recommended to use constant crosshead displacement rate when the
test is carried out until rupture.
© ISO 2013 – All rights reserved 3

---------------------- Page: 13 ----------------------

kSIST FprEN ISO 14544:2015
ISO 14544:2013(E)

5 Apparatus
5.1 Test machine
The machine shall be equipped with a system for measuring the force applied to the test specimen which
shall conform to grade 1 or better according to ISO 7500-1.
NOTE This should prevail during actual test conditions of, e.g. gas pressure and temperature.
5.2 Load train
The load train configuration shall ensure that the load indicated by the load cell and the load experienced
by the test specimen are the same.
The load train performance including the alignment system and the force transmitting system shall not
change because of heating.
The load train shall align the specimen axis with the direction of load application without introducing
bending or torsion in the specimen. The misalignment of the specimen shall be verified and documented
according to the procedure described in CEN/TS 15867:2009 The maximum percent bending shall not
−6
exceed 5 at an average strain of 500×10 .
NOTE 1 The alignment should be verified and documented in accordance with, for example, the procedure
described in CEN/TS 15867:2009.
There are two alternative means of load application.
a) Compression platens are connected to the load cell and on the moving crosshead. The parallelism of
these platens shall be better than 0,01 mm, in the loading area, at room temperature and they shall
be perpendicular to the load direction.
NOTE 1 The use of platens is not recommended for compression testing of 1D and 2D materials with low
thickness due to buckling.
NOTE 2 A compliant interlayer material between the test specimen and platens may be used for testing
macroscopically inhomogeneous materials to ensure even contact pressure. This material should be
chemically compatible with both test specimen and platen materials.
b) Grips are used to clamp and load the test specimen.
The grip design shall prevent the test specimen from slipping. The grips shall align the test specimen
axis with that of the applied force.
NOTE 3 Conformity with this requirement should be verified and documented according to, for example, the
[1]
procedure described in Reference.
NOTE 4 The grips or the platens may either be in the hot zone of the furnace or outside the furnace.
NOTE 5 When grips or platens are outside the furnace, a temperature gradient exists between the centre
of the specimen, which is at the prescribed temperature, and the ends that are at the same temperature as the
grips or platens.
5.3 Gastight test chamber
A gastight chamber could be used in this case.
The gastight chamber shall allow proper control of the test specimen environment in the vicinity of
the test specimen during the test. The installation shall be such that the variation of load due to the
variation of pressure is less than 1 % of the scale of the load cell being used.
4 © ISO 2013 – All rights reserved

---------------------- Page: 14 ----------------------

kSIST FprEN ISO 14544:2015
ISO 14544:2013(E)

Where a gas atmosphere is used, the gas atmosphere shall be chosen depending on the material to be
tested and on test temperature. The level of pressure shall be chosen depending: on the material to be
tested, on temperature, on the type of gas, and on the type of extensometry.
Where a vacuum chamber is used, the level of vacuum shall not induce chemical and/or physical
instabilities of the test specimen material, and of extensometer rods, when applicable.
5.4 Set-up for heating
The set-up for heating shall be constructed in such a way that the temperature gradient within the gauge
length is less than 20 °C at test temperature.
5.5 Extensometer
The extensometer shall be capable of continuously recording the longitudinal deformation at test temperature.
NOTE 1 The use of an extensometer with the greatest possible gauge length is recommended.
The linearity tolerance shall be less than or equal to 0,15 % of the extensometer range used.
The extensometer shall conform to class 1 or better of EN 10002-4. Two commonly used types of
extensometer are the mechanical extensometer and the electro-optical extensometer.
If a mechanical extensometer is used, the gauge length shall be the initial longitudinal distance between
the two locations where the extensometer rods contact the test specimen.
The rods may be exposed to temperatures higher than the test specimen temperature. Temperature and/or
environment induced structural changes in the rod material shall not affect the accuracy of deformation
measurement. The material used for the rods shall be compatible with the test specimen material.
NOTE 2 Care should be taken to correct for changes in calibration of the extensometer that may occur as a
result of operating under conditions different from calibration.
NOTE 3 Rod pressure onto the test specimen should be the minimum necessary to prevent slipping of the
extensometer rods.
If an electro-optical extensometer is used, electro-optical measurements in transmission require
reference marks on the test specimen. For this purpose rods or flags shall be attached to the surface
perpendicular to its axis. The gauge length shall be the distance between the two reference marks. The
material used for marks (and adhesive if used) shall be compatible with the test specimen material and
the test temperature and shall not modify the stress field in the specimen.
NOTE 4 The use of integral flags as parts of the test specimen geometry is not recommended because of stress
concentration induced by such features.
NOTE 5 An electro-optical extensometer is not recommended in the case where it’s impossible to distinguish
the colour of the reference marks and the test specimen.
5.6 Temperature measurement
For temperature measurement, either thermocouples conforming to IEC 60584-1 and IEC 60584-2 shall
be used or, where thermocouples not conforming to IEC 60584-1 and IEC 60584-2 or pyrometers are
used, calibration data shall be annexed to the test report.
5.7 Data recording system
A calibrated recorder may be used to record the force-deformation curve. However, the use of a digital
data recording system combined with an analogue recorder is recommended.
© ISO 2013 – All rights reserved 5

---------------------- Page: 15 ----------------------

kSIST FprEN ISO 14544:2015
ISO 14544:2013(E)

5.8 Micrometers
Micrometers used for the measurement of the dimensions of the test specimen shall conform to IS O3611.
6 Test specimens
6.1 General
The choice of specimen geometry depends on several factors, such as:
— nature of the material and of the reinforcement structure;
— type of heating system;
— type of loading system.
The volume in the gauge length shall be representative of the material and calibrated length shall be
chosen such as to avoid buckling failure.
NOTE A test piece volume of a minimum of 5 representative volume elements is recommended
6.2 Compression between platens
A Type 1 specimen is commonly used and is represented on Figure 1.
Recommended dimensions are given in Table 1.
0,05 A
B
0,05
A
d
B
Figure 1 — Type 1 specimen geometry
6 © ISO 2013 – All rights reserved
l
t
l

---------------------- Page: 16 ----------------------

kSIST FprEN ISO 14544:2015
ISO 14544:2013(E)

Table 1 — Recommended dimensions for a Type 1 specimen
Dimensions in millimetres
2D and xD Tolerance
l, calibrated length ≥ 15 ±0,5
l , total length ≥ 1,5 l ±0,5
t
d, circular or square section diameter or side length ≥ 8 ±0,2
r, radius of shoulder ≥ 10 ≥ 2
Parallelism of machined parts 0,05
Perpendicularity of machined parts 0,05
Concentricity of machined parts 0,05
A Type 2 specimen is sometimes used and is represented in Figure 2.
Recommended dimensions are given in Table 2.
d Ø d
Figure 2 — Type 2 specimen geometry
Table 2 — Recommended dimensions for a Type 2 specimen
Dimensions in millimetres
1D, 2D and xD Tolerance
l, calibrated length ≥ 10 ±0,5
d, circular or square section diameter or side length ≥ 10 ±0,2
Parallelism of machined parts 0,05
Perpendicularity of machined parts 0,05
NOTE This specimen is mainly used when the thickness of the part is not sufficient to machine a specimen of
type 1.
6.3 Test specimen used with grips
For these types of specimens, the total length l depends on furnace and gripping system.
t
A Type 3 specimen is represented in Figure 3.
Recommended dimensions are given in Tables 3 and 4.
© ISO 2013 – All rights reserved 7
l
l

---------------------- Page: 17 ----------------------

kSIST FprEN ISO 14544:2015
ISO 14544:2013(E)

A
b
2
b
1
A-A
h
A
l
l
t
Figure 3 — Type 3 specimen geometry
Table 3 — Recommended dimensions for a Type 3 specimen
Dimensions in millimetres
2D and xD Tolerance
l, calibrated length ≥ 15 ±0,5
h, thickness ≥ 2 ±0,2
b , width in the calibrated length ≥ 8 ±0,2
1
b , width b = αb with α = 1,2 to 2 ±0,2
2 2 1
r, radius of shoulder ≥ 30 ±2
Parallelism of machined parts 0,05
Table 4 — Alternative recom
...