prEN 15365

SLOVENSKI STANDARD
01-oktober-2024
Sodobna tehnična keramika - Mehanske lastnosti keramičnih vlaken pri visokih
temperaturah v nereaktivnem okolju - Ugotavljanje lezenja po metodi hladnega
spajanja (cold end method)
Advanced technical ceramics - Mechanical properties of ceramic fibres at high
temperature in a non-reactive environment - Determination of creep behaviour by the
cold grip method
Hochleistungskeramik - Mechanische Eigenschaften von Keramikfasern bei hohen
Temperaturen in einer reaktionsfreien Umgebung - Bestimmung des Kriechverhaltens im
Kaltverbindungsverfahren
Céramiques techniques avancées - Propriétés mécaniques des fibres céramiques à
haute température sous environnement non réactif - Détermination du comportement au
fluage par la méthode des mors froids
Ta slovenski standard je istoveten z: prEN 15365
ICS:
81.060.30 Sodobna keramika Advanced ceramics
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2024
ICS 81.060.30 Will supersede EN 15365:2010
English Version
Advanced technical ceramics - Mechanical properties of
ceramic fibres at high temperature in a non-reactive
environment - Determination of creep behaviour by the
cold grip method
Céramiques techniques avancées - Propriétés Hochleistungskeramik - Mechanische Eigenschaften
mécaniques des fibres céramiques à haute température von Keramikfasern bei hohen Temperaturen in einer
sous environnement non-réactif - Détermination du reaktionsfreien Umgebung - Bestimmung des
comportement au fluage par la méthode des mors Kriechverhaltens im Kaltverbindungsverfahren
froids
This draft European Standard is submitted to CEN members for enquiry. 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye 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: Rue de la Science 23, B-1040 Brussels
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 15365:2024 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Principle . 7
5 Significance and use . 9
6 Apparatus . 9
6.1 Test installations . 9
6.2 Load train . 9
6.3 Test chamber . 9
6.4 Set-up for heating. 10
6.5 Temperature measurement . 10
6.6 Control of deformation . 10
6.7 Data recording system . 10
6.8 Determination of fibre cross sectional area . 10
7 Test specimens . 10
7.1 Test specimen preparation . 10
7.2 Number of test specimens . 12
8 Test procedures . 12
8.1 Determination of the temperature profile in the furnace . 12
8.2 Test set-up: Determination of the temperature profile and of the different lengths of
each temperature zone in the furnace . 12
8.3 Test set-up: Loading considerations . 12
8.4 Test technique . 12
8.5 Test validity . 14
9 Calculation of results . 14
9.1 Creep stress . 14
9.2 Creep strain at time t . 15
10 Test report . 16
Bibliography . 17

European foreword
This document (prEN 15365:2024) has been prepared by Technical Committee CEN/TC 184 “Advanced
technical ceramics”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 15365:2010.
EN 15365:2024 includes the following significant technical changes with respect to EN 15365:2010:
— title updated;
— editorial revision.
1 Scope
This document specifies the conditions for the determination of the tensile creep deformation and failure
behaviour of single filaments of ceramic fibres at high temperature and under test conditions that prevent
changes to the material as a result of chemical reaction with the test environment.
This document applies to continuous ceramic filaments taken from tows, yarns, braids and knittings,
which have strains to fracture less than or equal to 5 %.
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.
EN 60584 (all parts), Thermocouples
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
creep
time-dependent increase of gauge length starting from the time when the constant specified level of force
is reached
3.2
creep threshold temperature
T
t
minimum temperature at which creep is detected
3.3
specimen temperature
T
temperature which varies along the fibre length in the cold grips case
Note 1 to entry: See 8.2.
3.4
specimen temperature in the zone
T
i
temperature defined as: T ≤ T ≤ T + i ΔT
t i t
3.5
total length
L
total length of the ceramic filament between the grips
3.6
length
L
i
length of the ceramic filament at temperature T
i
3.7
initial effective cross sectional area
A
initial cross sectional area of the ceramic filament within the gauge length
3.8
applied tensile force
F
constant force applied to the ceramic filament during the test
3.9
applied tensile stress
σ
applied tensile force divided by the initial cross sectional area
3.10
longitudinal deformation
ΔL
change in the total length of the ceramic filament caused by creep
3.11
longitudinal deformation
ΔL
i
change of the filament caused by creep at temperature T
i
3.12
tensile creep strain
ε
cr(T)
relative change in length in the controlled zone at time t, caused by creep at the temperature T
Note 1 to entry: The value corresponding to rupture is denoted ε .
cr,m
3.13
creep rupture time
t
cr,m
time elapsed from the moment when loading is completed until the moment of rupture
3.14
creep strain rate

ε
cr(T)
change in creep strain per unit time at time t at the temperature T
i
3.15
creep type
primary, secondary or tertiary creep
3.16
primary creep
part of the creep strain versus time curve which presents a decreasing creep strain rate
Note 1 to entry: See Figure 1.
3.17
secondary creep
part of the creep strain versus time curve which presents a constant creep strain rate
Note 1 to entry: See Figure 1.
3.18
tertiary creep
part of the creep strain versus time curve which presents an increasing creep strain rate
Note 1 to entry: See Figure 1.

a) Creep strain versus time
b) Creep strain rate versus time
Key
1 Creep strain ε cr
2 Time t
3 Primary creep
4 Secondary creep
5 Tertiary creep
6 
Creep strain rate ε (creep strain with time)
cr
7 Time
8 Primary creep
9 Secondary creep
10 Tertiary creep
Figure 1 — Creep strain and creep strain rate versus time curves
4 Principle
A ceramic filament is heated to the test temperature and loaded in tension until a specified level of force.
This force is maintained at a constant level for a specified time or until rupture. The variation in the
ceramic filament length is recorded in relation to time.
The specimen is held in cold grips and heated by a furnace. This experimental configuration provokes
temperature variations along the filament, which have to be taken into account in order to determine the
creep properties as function of temperature. Prior to testing, the temperature profile inside the furnace
is established over the temperature range. The temperature range is then divided into several
temperature zones defined by the operator, according to the following graph.
Key
T Temperature (°C)
l Length of the furnace
P Position (mm)
En Entrance
Ex Exit
L total length of the ceramic filament between the groups
L = L + 2L
0 2ΔT ΔT
where
L is the furnace length where the temperature T is in the range T + ΔT ≤ T ≤ T + 2 ΔT;
2ΔT t t
L is the furnace length where the temperature T is in the range T ≤ T ≤ T + ΔT.
ΔT t t
Figure 2 — Temperature profile in furnace
If T is considered to be the lowest temperature at which creep is observed, the temperature profile can
t
be divided in several intervals as a function of T and ΔT, where ΔT is the difference in temperature
t
between the different zones, fixed by the operator.
Considering i, the entire number of zones, and L, the total fibre length, the following lengths are defined:
— L is the furnace length where the temperature T is in the range 20 °C ≤ T ≤ T ;
20 t
— L is the furnace length where the temperature T is in the range T ≤ T ≤ T + ΔT;
ΔT t t
— L is the furnace length where the temperature T is in the range T + ΔT ≤ T ≤ T + 2 ΔT;
2ΔT t t
— L is the furnace length where the temperature T is in the range T + (i – 1) ΔT ≤ T ≤ T + i ΔT.
iΔT t t
Then L can be written:
...