Bsi bs en 00658 2 2002 (2003)

BS EN
658-2:2002

BRITISH STANDARD

Advanced technical
ceramics — Mechanical
properties of ceramic
composites at room
temperature —

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Part 2: Determination of compression
properties

The European Standard EN 658-2:2002 has the status of a
British Standard

ICS 81.060.30

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BS EN 658-2:2002

National foreword
This British Standard is the official English language version of
EN 658-2:2002. It supersedes DD ENV 658-2:1993 which is withdrawn.
The UK participation in its preparation was entrusted to Technical Committee
RPI/13, Advanced technical ceramics, which has the responsibility to:
—

aid enquirers to understand the text;

—

present to the responsible international/European committee any
enquiries on the interpretation, or proposals for change, and keep the
UK interests informed;

—

monitor related international and European developments and
promulgate them in the UK.

A list of organizations represented on this committee can be obtained on
request to its secretary.
Cross-references
The British Standards which implement international or European
publications referred to in this document may be found in the BSI Catalogue
under the section entitled “International Standards Correspondence Index”, or
by using the “Search” facility of the BSI Electronic Catalogue or of British
Standards Online.

This publication does not purport to include all the necessary provisions of a
contract. Users are responsible for its correct application.

This British Standard was
published under the authority
of the Standards Policy and
Strategy Committee on
7 March 2003

Summary of pages
This document comprises a front cover, an inside front cover, the EN title page,
pages 2 to 18, an inside back cover and a back cover.
The BSI copyright date displayed in this document indicates when the
document was last issued.

Amendments issued since publication
Amd. No.

Date

Comments

© BSI 7 March 2003

ISBN 0 580 41372 1

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EUROPEAN STANDARD

EN 658-2

NORME EUROPÉENNE
EUROPÄISCHE NORM

December 2002

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ICS 81.060.30

Supersedes ENV 658-2:1993

English version

Advanced technical ceramics - Mechanical properties of ceramic
composites at room temperature - Part 2: Determination of
compression properties
Céramiques techniques avancées - Propriétés mécaniques

des céramiques composites à température ambiante Partie 2: Détermination des propriétés en compression

Hochleistungskeramik - Mechanische Eigenschaften von
keramischen Verbundwerkstoffen bei Raumtemperatur Teil 2: Bestimmung der Eigenschaften unter Druck

This European Standard was approved by CEN on 16 October 2002.
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. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the Management Centre or to any CEN member.
This European Standard exists 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 Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: rue de Stassart, 36

© 2002 CEN

All rights of exploitation in any form and by any means reserved
worldwide for CEN national Members.

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B-1050 Brussels

Ref. No. EN 658-2:2002 E

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EN 658-2:2002 (E)

Contents
page

1

Scope ..............................................................................................................................................................4

2

Normative references ....................................................................................................................................4

3

Principle ..........................................................................................................................................................4

4

Terms, definitions and symbols ...................................................................................................................4

5

5.1
5.2
5.3
5.3.1
5.3.2
5.4
5.5

Apparatus .......................................................................................................................................................6
Test machine ..................................................................................................................................................6
Load train........................................................................................................................................................6
Strain measurement ......................................................................................................................................6
Strain gauges .................................................................................................................................................6
Extensometry .................................................................................................................................................7
Data recording system ..................................................................................................................................7
Dimension measuring devices .....................................................................................................................7

6
6.1
6.2

Test specimens ..............................................................................................................................................7
Compression between platens .....................................................................................................................8
Test specimen used with grips...................................................................................................................10

7
7.1
7.2

Test specimen preparation .........................................................................................................................13

Machining and preparation .........................................................................................................................13
Number of test specimens ..........................................................................................................................13

8
8.1
8.2
8.3
8.4
8.4.1
8.4.2
8.4.3
8.5

Test procedure .............................................................................................................................................13
Displacement rate ........................................................................................................................................13
Measurement of test specimen dimensions .............................................................................................14
Buckling ........................................................................................................................................................14
Testing technique ........................................................................................................................................14
Specimen mounting.....................................................................................................................................14
Extensometers .............................................................................................................................................14
Measurements ..............................................................................................................................................14
Test validity ..................................................................................................................................................15

9
9.1
9.2
9.3
9.4

Calculation of results ..................................................................................................................................15

Test specimen origin ...................................................................................................................................15
Compression strength.................................................................................................................................15
Strain at maximum compression force .....................................................................................................15
Proportionality ratio or pseudo-elastic modulus, elastic modulus ........................................................16

10

Test report ....................................................................................................................................................17

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Foreword......................................................................................................................................................................3


EN 658-2:2002 (E)

Foreword

This document (EN 658-2:2002) has been prepared by Technical Committee CEN /TC 184, "Advanced technical
ceramics", the secretariat of which is held by BSI.
This European Standard shall be given the status of a national standard, either by publication of an identical text or
by endorsement, at the latest by June 2003, and conflicting national standards shall be withdrawn at the latest by

June 2003.
This document supersedes ENV 658-2 :1993.
EN 658 consists of the following parts, under the general title "Advanced technical ceramics – Mechanical
properties of ceramic composites at room temperature"


Part 1 : Determination of tensile properties



Part 2 : Determination of compressive properties



Part 3 : Determination of flexural strength

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

Part 4 : Determination of interlaminar shear strength by compression loading of notched test specimens



Part 5 : Determination of interlaminar shear strength by short span bend test (three-points)



Part 6 : Determination of interlaminar shear strength by double-punch shearing

According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland,
France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain,
Sweden, Switzerland and the United Kingdom.

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EN 658-2:2002 (E)

1

Scope

This part of this European Standard describes a method for determination of compression properties of ceramic
matrix composite materials with continuous fibre reinforcement at room temperature. This method applies to all
ceramic matrix composites with a continuous fibre reinforcement, unidirectional (1D), bidirectional (2D), and
tridirectional (xD, with 2 < x ≤ 3) as defined in ENV 13233, loaded along one principal axis of reinforcement.
Two cases are distinguished:


compression between platens;



compression using grips.

2

Normative references

This European Standard incorporates by dated or undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text, and the publications are listed hereafter. For
dated references, subsequent amendments to or revisions of any of these publications apply to this European
Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the
publication referred to applies (including amendments).
ENV 13233:1998, Advanced technical ceramics - Ceramic composites - Notations and symbols.
EN ISO 7500-1:1999, Metallic materials - Verification of static uniaxial testing machines - Part 1:
Tension/compression testing machines (ISO 7500-1:1999).

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ISO 3611, Micrometer callipers for external measurements

3

Principle

A test specimen of specified dimensions is loaded in compression. The test is performed at a constant crosshead
displacement rate or at a constant deformation rate.
NOTE 1

Constant loading rate is only allowed in the case of linear stress strain behaviour up to failure.

NOTE 2
failure.

When applied, it is recommended to use constant cross head displacement rate when the test is carried out up to

The force and longitudinal deformation are measured and recorded simultaneously.

4

Terms, definitions and symbols

For the purposes of this European Standard, the following terms and definitions and the symbols given in
ENV 13233 apply.
4.1
calibrated length, l
the part of the test specimen which has uniform and minimum cross-section area
4.2
gauge length, Lo
initial distance between reference points on the test specimen in the calibrated length

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EN 658-2:2002 (E)

4.3
initial cross-section area, Ao
initial cross-section of the test specimen within calibrated length
4.4
longitudinal deformation, ∆L
decrease in the gauge length between reference points under a compression force. Its value corresponding to the
maximum force shall be denoted ∆Lc,m
4.5
compression strain, ε
relative change in the gauge length defined as the ratio ∆L/Lo. Its value corresponding to the maximum force shall
be denoted εc,m
4.6
compression stress, σ
the compression force supported by the test specimen at any time in the test divided by the initial cross-section
area
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4.7
maximum compression force, Fc,m
highest recorded compression force in a compression test on the test specimen when tested to failure
4.8
compression strength, σc,m
ratio of the maximum tensile force to the initial cross-section area

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4.9
proportionality ratio or pseudo-elastic modulus Ep, elastic modulus E
the slope of the linear section of the stress-strain curve, if any. 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 characterised by a linear section, the
proportionality ratio Ep is defined as:
 − 1
Ep ( 1,  2 ) = 2

2 −
1

(1)

where
(ε1, σ1) and (ε2, σ2) lie near the lower and the upper limits of the linear section of the stress-strain curve (see
Figures 1 and 2).
The proportionality ratio or pseudo-elastic modulus is termed the elastic modulus, E, in the single case where
the linearity starts near the origin (see Figure 2);
b) material with non-linear section in the stress-strain curve
In this case only stress-strain couples can be fixed.
4.10
axial strain
average of the longitudinal strain measured at the surface of the test specimen at specified locations

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EN 658-2:2002 (E)

4.11
bending strain
the difference between the longitudinal strain at a given location on the test specimen surface and the axial strain
4.12
percent bending
the bending strain times 100 divided by the axial strain

5

Apparatus

5.1 Test machine
The machine shall be equiped with a system for measuring the force applied to the test specimen which shall
conform to grade 1 or better according to EN ISO 7500-1:1999.

5.2 Load train
The load train is composed of the moveable and fixed crosshead, the loading rods and the grips or platens. Load
train couplers may additionally be used to connect the grips or platens to the loading rods.
The load train shall align the specimen axis with the direction of load application without introducing bending or
torsion in the specimen. The maximum percent bending shall not exceed 5 at an average strain of 500 ⋅ 10 −6 .
There are two alternative means of load application:
a)

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compression platens are connected to the load cell and on the moving cross head. The parallelism of these
platens shall be better than 0,01 mm, in the loading area and they shall be perpendicular to the load direction.

NOTE 2
A compliant interlayer material between the test specimen and platens can be used for testing macroscopically
inhomogeneous materials to ensure uniform contact pressure.

When the dimensions of specimen are such that buckling may occur, it is recommended to use an antibuckling
tool such as one of those which are described in EN ISO 14126. This tool should not induce parasitic stresses
during loading of the specimen;
b) grips are used to clamp and load the test specimen.
The grip design shall prevent the test specimen from slipping.
The grips must align the test specimen axis with that of the applied force.
NOTE

This point should be verified and documented, according to, for example the procedure described in WI 00184136.

5.3 Strain measurement
For continuous measurement of the longitudinal deformation as a function of the applied force either strain gauges
or a suitable extensometer complying with EN 10002-4 may be used. Measurement of longitudinal deformation
over a length as large as possible compatible with the calibrated length of the specimen is recommended.
5.3.1

Strain gauges

Strain gauges are used for the verification of the alignment on the specimen. They may also be used for measuring
longitudinal deformation during testing. In both cases, the length of the strain gauges shall be such that the
readings are not affected by local features on the surface of the specimen such as fibre crossovers. Care shall be

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NOTE 1
The use of platens is not recommended for compression testing of 1D and 2D materials with low thicknesses
because of buckling.


EN 658-2:2002 (E)

taken to ensure that the strain gauge readings are not influenced by the surface preparation and the adhesive
used.
5.3.2

Extensometry

The linearity tolerance of the extensometer shall be lower than 0,15 % of the extensometer range used.
The commonly used type of extensometer is:
5.3.2.1

Mechanical extensometer

For a mechanical extensometer the gauge length corresponds to the initial longitudinal distance between the two

locations where the extensometer rods contact the specimen. The mounting of the rods on the specimen shall
prevent slippage of the extensometer as well as failure initiation under the contact points. The contact forces shall
not introduce bending greater than that allowed in 5.2.
Another type of extensometer which is sometimes used is:
5.3.2.2

Electro-optical extensometer

Electro-optical measurements in transmission require reference marks on the specimen. For this purpose rods or
flags are attached to the specimen surface perpendicular to the longitudinal specimen axis. The gauge length
corresponds to the initial longitudinal distance between the two reference marks.
NOTE
The use of integral flags as part of the specimen geometry is not recommended because of stress concentrations
induced by such features.

5.4 Data recording system

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A calibrated recorder may be used to record force-deformation curves. The use of a digital data recording system
combined with an analogue recorder is recommended.

5.5 Dimension measuring devices
Devices used for measuring linear dimensions of the test specimen shall be accurate to ± 0,1 mm. Micrometres
shall be in accordance with ISO 3611.

6

Test specimens




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The choice of specimen geometry depends on several parameters:
the nature of the material and of the reinforcement structure;
the type of loading system.

The ratio between the length of the specimen submitted to buckling and the thickness of the test specimen and
also the stiffness of the material will influence the resistance of the test specimen towards buckling.
If buckling occurs, it will be necessary to modify the dimensions of the test specimen or alternatively to use an
antibuckling tool.
The volume in the gauge length shall be representative of the material.
Two types of test specimens can be distinguished:


as fabricated test specimens, where only the length and the width are machined to the specified size. In this
case, the two faces of the test specimen may present an irregular surface;

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EN 658-2:2002 (E)



machined test specimens, where the length and the width and also the two sides of the test specimen have
been machined.

Tolerance on thickness is only for machined test specimens. For as-fabricated test specimens the difference in
thickness taken out of three measurements (at the centre and at each end of the calibrated length) shall not exceed
5 % of the average of the three measurements.

6.1 Compression between platens
The test specimen geometry and/or compliant interlayers may be adapted in order to avoid buckling and damage at
the edges due to contact forces.
Type 1 is commonly used and is represented in Figure 1 below.
Recommended dimensions are given in Table 1.

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EN 658-2:2002 (E)

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Figure 1

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EN 658-2:2002 (E)

Table 1
Dimensions in millimetres
1D, 2D, xD

Tolerance

≥ 15

± 0,5

≥ 1,5 l

± 0,5

d, cylindrical or square section side

length or diameter

≥8

± 0,2

Parallelism of machined parts

0,05

Perpendicularity of machined parts

0,05

Concentricity of machined parts

0,05

l, calibrated length
lt, total length

Type 2, which is sometimes used, is represented in Figure 2 below and recommended dimensions are given in
Table 2.

Figure 2
Table 2
Dimensions in millimetres
1D, 2D, xD

Tolerance

l, calibrated length

≥ 10

± 0,5

d, cylindrical or square section

≥ 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 test specimen of type 1.

6.2 Test specimen used with grips

These test specimens allow testing of low thickness specimens without using an antibuckling tool.
It is however necessary to verify that the chosen L/h ratio does not lead to buckling.
Type 3 is represented in Figure 3 and recommended dimensions are given in Table 3a) and Table 3b).

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For these types of test specimens, the total length lt depends on the gripping system.


EN 658-2:2002 (E)

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Figure 3
Table 3a)
Dimensions in millimetres
1D, 2D, xD

Tolerance

l, calibrated length

≥ 15

± 0,5

h, thickness

≥3

± 0,2

b1, width in the calibrated length

≥8

± 0,2

b2, width

b2 = αb1 with α : 1,2 to 2

± 0,2

r, radius

≥ 30

±2

Plane parallelism of machined parts

0,05

Table 3b)

Dimensions in millimetres
1D, 2D, xD

Tolerance

l, calibrated length

≤ 15

± 0,5

h, thickness

≥3

± 0,2

b1, width in the calibrated length

≥8

± 0,2

b2, width

b2 = αb1 with α : 1,2 to 2

± 0,2

r, radius

≥ 30

±2

Plane parallelism of machined parts

0,05

NOTE
This type of test specimen is recommended in the case of buckling with specimen of Table 3a). With this type of
specimen, it is very difficult to obtain strain measurements.

Type 4 is a straight-sided specimen. It is represented in Figure 4 and dimensions are given in Table 4.

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EN 658-2:2002 (E)

Figure 4
Table 4
Dimensions in millimetres
1D, 2D, xD

Tolerance

lt, total length

≥ 100

± 0,5

l, calibrated length

≥ 40

± 0,2

h, thickness

≥3

± 0,2

b, width

≥ 10

± 0,2

Plane parallelism of machined part

0,05

NOTE
This test specimen is easy to machine and its use allows mainly the determination of modulus; it should not be used
for strength measurement.

Type 5 is a straight sided specimen equipped with tabs. The tabs are metallic or composite, bonded or cured onto
the test specimen. The dimensions are given in Table 5 and the specimen is represented in Figure 5. This type of
specimen is mainly used for 1D, 2D and xD (with 2 < x < 3) materials.
Table 5
Dimensions in millimetres
1D, 2D, xD

Tolerance

lt, total length

≥ 100

± 0,5

l, calibrated length

≥ 40

± 0,2

Tab length

≥ 30

± 0,2

h, thickness

≥3

± 0,2

b, width

≥ 10

± 0,2

Plane parallelism of machined parts and
of tabs faces

0,05

NOTE

The thickness of the tabs is generally between 1 mm and 3 mm.

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EN 658-2:2002 (E)

Figure 5
Type 6 test specimens:
All test specimens designed for high temperature testing (see ENV 12290 and ENV 12291) can be used for room
temperature testing.
NOTE
It is customary to obtain results at room temperature when testing a material at high temperature and to do so the
same specimens are used. However, the costs of specimens for high temperature tests are generally much higher and these
types are not used when only room temperature properties are required.

7

Test specimen preparation

7.1 Machining and preparation
During cutting out, care shall be taken to align the test specimen axis with the desired fibre related loading axis.
Machining parameters which avoid damage to the material shall be established and documented. These
parameters shall be adhered to during test specimen preparation.

7.2 Number of test specimens

NOTE

8

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At least five valid test results (8.5) are required.
If statistical evaluation is required, the number of test specimens should be in accordance with ENV 843-5.

Test procedure

8.1 Displacement rate
Use a displacement or deformation rate which allows specimen failure within 1 min.

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EN 658-2:2002 (E)

8.2 Measurement of test specimen dimensions
The cross-section area is determined at the centre of the specimen and at each end of the calibrated length. The
arithmetic means of the measurements shall be used for calculations.
Necessary dimensions to calculate cross-section area are measured with an accuracy of ± 0,01 mm.

8.3 Buckling
During a compression test, the test specimen may be subjected to buckling. To be sure of the validity of the test, it
is necessary to verify that no buckling occurs in the conditions of the test.
This verification shall be carried out every time there is a change in material, in specimen geometry, in gripping

configuration, etc.
The bucking is acceptable if the difference between strain measured in the middle of calibrated lengths on the
opposite width faces on the verification specimen for the values of stress comprised between (0,1 σc,m - 0,9 σc,m)
remains such that:

ε' −ε"
ε' + ε"

≤ 0,05

where
ε’

is the compression strain measured on the width face;

ε’’

is the compression strain measured on the opposite face for the same strain in the same
cross-section.

If this is not the case, another test specimen shall be defined with a different ratio l/h.
NOTE
One possibility is to place on opposite sides of the test specimen and test according 8.4. Difference in extensometer
responses will indicate buckling.

8.4 Testing technique
8.4.1

Specimen mounting

Install the test specimen in the gripping system or loading system with its longitudinal axis coinciding with that of
the test machine.
Care shall be taken not to induce flexural or torsional loads.
8.4.2

Extensometers

If used, install the extensometer centrally within the calibrated length.
8.4.3

Measurements



Zero the load cell;



zero the extensometer (or strain gauges if used);

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In the case of circular specimen, the verification shall be measured at opposite circonferential position in the same
cross-section.


EN 658-2:2002 (E)



record the force versus longitudinal deformation;



load the test specimen;



note the position of fracture location relative to the mid-point, to the nearest 1 mm.

8.5 Test validity



failure to specify and record test conditions;



failure to meet specified test conditions;



failure to meet buckling criteria according to 8.3;



specimen slippage;



extensometer slippage or strain gauge failure;



fracture in an area outside the calibrated length.

9

Calculation of results

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The following circumstances invalidate a test:

9.1 Test specimen origin
A diagram illustrating the reinforcement directions of the material with respect to the longitudinal axis of the test
specimen shall always accompany the test results.

9.2 Compression strength
Calculate the compression strength using the following equation:
 c,m =

Fm

(2)

Ao

where
σc,m

is the compressive strength, in megapascal (MPa);

Fm

is the maximum compressive force, in newton (N);

Ao

is the initial cross-section area of the specimen, in square millimetre (mm2).

9.3 Strain at maximum compression force
Calculate the strain using the following equation:

c,m =

 c,m

(3)

Lo

where

εc,m

is the strain at the maximum compression force;

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EN 658-2:2002 (E)

∆Lc,m

is the longitudinal deformation at the maximum compression force in millimetres measured by the
extensometer;

Lo

is the gauge length, in millimetre (mm).

9.4 Proportionality ratio or pseudo-elastic modulus, elastic modulus
Calculate the proportionality ratio or pseudo-elastic modulus Ep defined between two points ( ∆L1 ,F1) and
( ∆L2 ,F2) measured near the lower and upper limits of the linear part of the force-deformation record, according to
the following equation:
9.4.1

E p (σ 1 ,σ 2 )=

Lo ( F2 − F1 )
⋅ 10 −3
Ao (∆L2 −∆L1 )

(4)

where
Ep

is the pseudo-elastic modulus, in gigapascal (GPa);

F

is the tensile force at the defined point on the force-longitudinal deformation curve, in newton (N);

Ao

is the initial cross-section area of the specimen, in square millimetre (mm2);

Lo

is the gauge length, in millimetre (mm);

∆L

is the longitudinal deformation corresponding to F, in millimetre (mm).

9.4.2 Where the material has a linear behaviour at the origin, calculate the elastic modulus according to the

following equation:
E =

F Lo
⋅ 10 −3
Ao ∆L

(5)

where
E

is the elastic modulus, in gigapascal (GPa);

F

is the tensile force at a point in the linear part of the force-longitudinal deformation curve, in
newton (N);

Ao

is the initial cross-section area of the specimen, in square millimetre (mm2);

Lo

is the gauge length, in millimetre (mm);

∆L

is the longitudinal deformation corresponding to F, in millimetre (mm).

Any point (∆L, F) on the linear section of the force-deformation record may be used for its determination.
9.4.3 For materials with no linear section in the stress strain curve, it is recommended to use the couples of
stress strain values corresponding to stresses of 0,1σc,m and 0,5σc,m unless other couples are fixed by agreement
between parties.
NOTE
In the case where a type 5 test specimen intended for use at high temperature is tested at room temperature and
where the test specimen is protected by a coating intended for specific environmental conditions, the calculation procedure of
ENV 12291 should be used. Two cross sections are defined: effective cross section and apparent cross section.

16
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EN 658-2:2002 (E)

10 Test report
The test report shall contain at least the following information:
a)

name and address of the testing establishment;

b)

date of the test, unique identification of report and of each page, customer name and address and signatory;

c)

a reference to this European standard, i.e. "determined in accordance with EN 658-2";

d)

test piece drawing or reference;

e)

description of test material (material type, manufacturing code, batch number);

f)

description of test set-up (gripping system or loading system, extensometer or gauge type, load cell);

g)

displacement rate or deformation rate or loading rate;

h)

number of tests carried out and the number of valid results obtained;

i)

force-longitudinal deformation record;

j) valid results, mean value and standard deviations (for Gaussian distribution) of the compression strength, the
compression strain at maximum compression force, the (pseudo-)elastic modulus and proportionality ratio (if
applicable);
k)

failure location of all the test specimens used to obtain the above results.
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EN 658-2:2002 (E)

Bibliography

EN 10002-4, Metallic materials - Tensile test - Part 4: Verification of extensometers used in uniaxial testing.

[2]

ENV 843-5, Advanced technical ceramics - Monolithic ceramics - Mechanical tests at room temperature Part 5: Statistical analysis

[3]

ENV 12290, Advanced technical ceramics - Mechanical properties of ceramic composites at high
temperature under inert atmosphere - Determination of compression properties.

[4]

ENV 12291, Advanced technical ceramics - Mechanical properties of ceramic composition at high
temperature in air at atmosphere pressure - Determination of compression properties.

[5]

EN ISO 14126, Fibre-reinforced plastic composites - Determination of compressive properties in the inplane direction (ISO 14126:1999).

[6]

WI 00184136 1, Code of practice for the measurement of bending in uniaxially loaded tension-compression
test specimens

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[1]

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