Advanced technical ceramics - Thermomechanical properties of monolithic ceramics - Part 5: Determination of elastic moduli at elevated temperatures

This part of EN 820 describes methods for determining the elastic moduli, specifically Young's modulus, shear modulus and Poisson's ratio, of advanced monolithic technical ceramics at temperatures above room temperature. The standard prescribes three alternative methods for determining some or all of these three parameters:
A   the determination of Young's modulus by static flexure of a thin beam in three- or four-point bending.
B   the determination of Young's modulus by forced longitudinal resonance, or Young's modulus, shear modulus and Poisson's ratio by forced flexural and torsional resonance, of a thin beam.
C   the determination of Young's modulus from the fundamental natural frequency of a struck bar (impulse excitation method).
This part of EN 820 extends the above-defined room-temperature methods described in EN 843-2 to elevated temperatures. All the test methods assume the use of homogeneous test pieces of linear elastic materials. The test assumes that the test piece has isotropic elastic properties. At high porosity levels all of the methods can become inappropriate. The maximum grain size (see EN 623-3), excluding deliberately added whiskers, should be less than 10 % of the minimum dimension of the test piece.
NOTE 1   Method C in EN 843-2 based on ultrasonic time of flight measurement has not been incorporated into this part of EN 820. Although the method is feasible to apply, it is specialised, and outside the capabilities of most laboratories. There are also severe restrictions on test piece geometries and methods of achieving pulse transmission. For these reasons this method has not been included in EN 820-5.
NOTE 2   The upper temperature limit for this test depends on the properties of the test pieces, and can be limited by softening within the timescale of the test. In addition, for method A there can be limits defined by the choice of test jig construction materials.

Hochleistungskeramik - Thermomechanische Eigenschaften monolithischer Keramik - Teil 5: Bestimmung der elastischen Moduln bei erhöhten Temperaturen

Dieser Teil von EN 820 legt Verfahren zum Bestimmen der elastischen Moduln, insbesondere des Elastizitätsmoduls,
des Schermoduls und der Poissonzahl, von monolithischen Hochleistungskeramiken bei Temperaturen
über Raumtemperatur fest. Die Norm legt drei alternative Verfahren zum Bestimmen aller drei
genannten oder einzelner dieser Parameter fest:
A Bestimmung des Elastizitätsmoduls durch statisches Biegen eines dünnen Balkens in einem Drei-Punktoder
Vier-Punkt-Biegeversuch;
B Bestimmung des Elastizitätsmoduls durch erzwungene Längsresonanz oder des Elastizitätsmoduls, des
Schermoduls und der Poissonzahl durch erzwungene Biege- und Torsionsresonanz eines dünnen
Balkens;
C Bestimmung des Elastizitätsmoduls aus der Grundeigenfrequenz eines durch Schlag angeregten Stabes
(Impulsanregungsverfahren).
Dieser Teil von EN 820 erweitert die bereits definierten Verfahren für Raumtemperatur, die in EN 843-2
festgelegt sind, für die Anwendung bei erhöhten Temperaturen. Jedes dieser Prüfverfahren setzt die
Verwendung homogener Proben aus linear elastischem Werkstoff voraus. Des Weiteren werden für die
Prüfung isotrope elastische Eigenschaften der Probe vorausgesetzt. Bei hohen Porositätsgraden sind
möglicherweise alle diese Verfahren ungeeignet. Die maximale Korngröße (siehe EN 623-3) sollte, mit Ausnahme
der bewusst zugegebenen Haarkristalle, weniger als 10 % des kleinsten Maßes der Probe betragen.
ANMERKUNG 1 Das Verfahren C in EN 843-2, das auf Ultraschall-Laufzeitmessung beruht, wurde in diesem Teil von
EN 820 nicht berücksichtigt. Obwohl das Verfahren zur Anwendung geeignet ist, liegt es aufgrund der Spezialisierung für
die meisten Laboratorien außerhalb der Möglichkeiten. Außerdem gelten strenge Einschränkungen hinsichtlich der
Probengeometrie und der Verfahren zum Erreichen der Impulsübertragung. Aus diesen Gründen wurde das Verfahren
nicht in EN 820-5 aufgenommen.

Céramiques techniques avancées - Méthodes d'essai des céramiques monolithiques - Propriétés thermomécaniques - Partie 5: Détermination des modules élastiques à températures élevées

La présente partie de l’EN 820 décrit des méthodes de détermination des modules élastiques, en particulier du
module de Young, du module de cisaillement et du coefficient de Poisson des céramiques techniques avancées
à des températures supérieures à la température ambiante. La norme décrit trois méthodes possibles
permettant de déterminer un ou plusieurs de ces trois paramètres :
A détermination du Module de Young par flexion statique d’une poutre mince en trois ou quatre points.
B détermination du Module de Young par résonance longitudinale forcée ou détermination du module de
Young, du module de cisaillement et du coefficient de Poisson par résonance forcée en flexion et en
torsion d’une poutre mince.
C détermination du module de Young à partir de la fréquence naturelle fondamentale d’une barre que l’on
frappe (méthode d’excitation par impulsion).
La présente partie de l’EN 820 étend aux températures élevées les méthodes à température ambiante
définies ci-dessus et décrites dans l’EN 843-2. Toutes les méthodes d’essai supposent l’utilisation d’éprouvettes
homogènes faites en matériaux élastiques linéaires. L’essai est fait en considérant que l’éprouvette a des
propriétés élastiques isotropes. Toutes ces méthodes peuvent se révéler inappropriées pour des niveaux de
porosité élevés. II convient que la granulométrie maximale (voir l’EN 623-3), qui ne tient pas compte de l’ajout de
« whiskers », représente moins de 10 % de la plus petite dimension de l’éprouvette.
NOTE 1 La méthode C de l’EN 843-2 s’appuie sur le mesurage du temps de vol par ultrasons et n’a pas été
reprise dans cette partie de l’EN 820. Bien qu’il soit possible d’appliquer cette méthode, elle est spécialisée et la plupart
des laboratoires ne sont pas en mesure de l’utiliser. II y a également d’importantes restrictions portant sur la géométrie de
l’éprouvette et sur les méthodes d’obtention de la transmission de l’impulsion.

Sodobna tehnična keramika - Termomehanske lastnosti monolitske keramike - 5. del: Ugotavljanje elastičnih modulov pri povišanih temperaturah

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Publication Date
07-Jul-2009
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30-Jan-2010
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SLOVENSKI STANDARD
01-september-2009
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SIST-TS CEN/TS 820-5:2005
6RGREQDWHKQLþQDNHUDPLND7HUPRPHKDQVNHODVWQRVWLPRQROLWVNHNHUDPLNH
GHO8JRWDYOMDQMHHODVWLþQLKPRGXORYSULSRYLãDQLKWHPSHUDWXUDK
Advanced technical ceramics - Thermomechanical properties of monolithic ceramics -
Part 5: Determination of elastic moduli at elevated temperatures
Hochleistungskeramik - Thermomechanische Eigenschaften monolithischer Keramik -
Teil 5: Bestimmung der elastischen Moduln bei erhöhten Temperaturen
Céramiques techniques avancées - Propriétés thermomécaniques des céramiques
monolithiques - Partie 5: Détermination des modules élastiques à température élevées
Ta slovenski standard je istoveten z: EN 820-5:2009
ICS:
81.060.30 Sodobna keramika Advanced ceramics
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 820-5
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2009
ICS 81.060.30 Supersedes CEN/TS 820-5:2004
English Version
Advanced technical ceramics - Thermomechanical properties of
monolithic ceramics - Part 5: Determination of elastic moduli at
elevated temperatures
Céramiques techniques avancées - Propriétés Hochleistungskeramik - Thermomechanische
thermomécaniques des céramiques monolithiques - Partie Eigenschaften monolithischer Keramik - Teil 5:
5 : Détermination des modules élastiques à température Bestimmung der elastischen Moduln bei erhöhten
élevées Temperaturen
This European Standard was approved by CEN on 12 June 2009.
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 CEN 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 CEN Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 820-5:2009: E
worldwide for CEN national Members.

Contents Page
Foreword . 3
1 Scope. 4
2 Normative references . 4
3 Terms and definitions . 5
4 Method A: Static bending method . 5
4.1 Principle . 5
4.2 Apparatus . 5
4.3 Test pieces . 9
4.4 Procedure . 9
4.5 Calculation of results . 9
4.6 Accuracy and interferences . 11
5 Method B: Resonance method . 12
5.1 Principle . 12
5.2 Apparatus . 12
5.3 Test pieces . 15
5.4 Procedure . 15
5.5 Calculation of results . 16
5.6 Accuracy and interferences . 18
6 Method C: Impulse excitation method . 18
6.1 Principle . 18
6.2 Apparatus . 18
6.3 Test pieces . 21
6.4 Procedure . 21
6.5 Calculation . 21
6.6 Accuracy and interferences . 22
7 Test report . 22
7.1 General . 22
7.2 Method A . 23
7.3 Method B . 23
7.4 Method C . 24
Bibliography . 25

Foreword
This document (EN 820-5:2009) 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 January 2010, and conflicting national standards
shall be withdrawn at the latest by January 2010.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such
patent rights.
This document supersedes CEN/TS 820-5:2004.
EN 820 consists of five parts, under the general title "Advanced technical ceramics - Methods of
testing monolithic ceramics - Thermomechanical properties":
 Part 1: Determination of flexural strength at elevated temperatures
 Part 2: Determination of self-loaded deformation
 Part 3: Determination of resistance to thermal shock by water quenching
 Part 4: Determination of flexural creep deformation at elevated temperatures
 Part 5: Determination of elastic moduli at elevated temperatures
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,
Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom.
1 Scope
This part of EN 820 describes methods for determining the elastic moduli, specifically Young's modulus,
shear modulus and Poisson's ratio, of advanced monolithic technical ceramics at temperatures above
room temperature. The standard prescribes three alternative methods for determining some or all of
these three parameters:
A the determination of Young's modulus by static flexure of a thin beam in three- or four-point
bending.
B the determination of Young's modulus by forced longitudinal resonance, or Young's modulus,
shear modulus and Poisson's ratio by forced flexural and torsional resonance, of a thin beam.
C the determination of Young's modulus from the fundamental natural frequency of a struck bar
(impulse excitation method).
This part of EN 820 extends the above-defined room-temperature methods described in EN 843-2 to
elevated temperatures. All the test methods assume the use of homogeneous test pieces of linear elastic
materials. The test assumes that the test piece has isotropic elastic properties. At high porosity levels all
of the methods can become inappropriate. The maximum grain size (see EN 623-3), excluding
deliberately added whiskers, should be less than 10 % of the minimum dimension of the test piece.
NOTE 1 Method C in EN 843-2 based on ultrasonic time of flight measurement has not been incorporated into
this part of EN 820. Although the method is feasible to apply, it is specialised, and outside the capabilities of most
laboratories. There are also severe restrictions on test piece geometries and methods of achieving pulse
transmission. For these reasons this method has not been included in EN 820-5.
NOTE 2 The upper temperature limit for this test depends on the properties of the test pieces, and can be
limited by softening within the timescale of the test. In addition, for method A there can be limits defined by the
choice of test jig construction materials.
NOTE 3 Methods B and C may not be appropriate for materials with significant levels of porosity (i.e. > 15 %)
which cause damping and an inability to detect resonances or natural frequencies, respectively.
NOTE 4 This method does not provide for the effects of thermal expansion, i.e. the measurements are based
on room temperature dimensions. Depending upon the use to which the data are put, it can be necessary to
make a further correction by multiplying each dimensional factor in the relevant equations by a factor (1 + α ∆T)
where α is the mean linear expansion coefficient over the temperature interval ∆T from room temperature.
2 Normative references
The following referenced documents are indispensable for the application 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 820-1, Advanced technical ceramics — Method of testing monolithic ceramics — Thermo-
mechanical properties — Part 1: Determination of flexural strength at elevated temperatures
EN 843-1:2006, Advanced technical ceramics — Mechanical properties of monolithic ceramics at
room temperature — Part 1: Determination of flexural strength
EN 60584-2, Thermocouples — Part 2: Tolerances (IEC 60584-2:1982 + A1:1989)
EN 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 (ISO 7500-1:2004)
EN ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories
(ISO/IEC 17025:2005)
ISO 463, Geometrical Product Specifications (GPS) — Dimensional measuring equipment — Design
and metrological characteristics of mechanical dial gauges
ISO 3611, Micrometer callipers for external measurement
ISO 6906, Vernier callipers reading to 0,02 mm
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
Young's modulus
stress required in a material to produce unit strain in uniaxial extension or compression
3.2
shear modulus
shear stress required in a material to produce unit angular distortion
3.3
Poisson's ratio
negative value of the ratio of lateral strain to longitudinal strain in an elastic body stressed longitudinally
3.4
static elastic moduli
elastic moduli determined in an isothermal condition by stressing statically or quasistatically
3.5
dynamic elastic moduli
elastic moduli determined non-quasistatically, i.e. under adiabatic conditions, such as in the resonant,
ultrasonic pulse or impulse excitation methods
4 Method A: Static bending method
4.1 Principle
Using three- or four-point bending of a thin beam test piece, the elastic distortion is measured, from which
Young's modulus may be calculated according to thin beam equations.
4.2 Apparatus
4.2.1 Test jig, in accordance with that described in EN 820-1 for flexural strength testing at elevated
temperatures in terms of its function, i.e.
...

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