oSIST prEN ISO 19634:2021

Fine ceramics (advanced ceramics, advanced technical ceramics) - Ceramic composites - Notations and symbols (ISO 19634:2017)

This document defines the symbols to be used to represent physical, mechanical and thermal characteristics, as determined by methods described in relevant ISO publications, for ceramic matrix composites. It is aimed at avoiding confusion in reporting measurements and characteristics of products.
Where possible, the definitions are in accordance with the relevant parts of ISO 80000. In addition, the symbols used in undertaking measurements of these characteristics are also defined.

Hochleistungskeramik - Keramische Verbundwerkstoffe - Bezeichnungen und Formelzeichen (ISO 19634:2017)

Céramiques techniques - Céramiques composites - Notations et symboles (ISO 19634:2017)

Fina keramika (sodobna keramika, sodobna tehnična keramika) - Keramični kompoziti - Oznake in simboli (ISO 19634:2017)

General Information

• Status: Not Published
• Public Enquiry End Date: 31-May-2021
• ICS: 01.075 - Character symbols
• ICS: 81.060.30 - Advanced ceramics
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 25-Mar-2021
• Due Date: 12-Aug-2021
• Completion Date: 02-Jun-2021
• Ref Project: EN ISO 19634:2021 - Fine ceramics (advanced ceramics, advanced technical ceramics) - Ceramic composites - Notations and symbols (ISO 19634:2017)

RELATIONS

• Revised: SIST-TP CEN/TR 13233:2007 - Advanced technical ceramics - Notations and symbols
• Effective Date: 03-Feb-2021

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN ISO 19634:2021
01-maj-2021
Fina keramika (sodobna keramika, sodobna tehnična keramika) - Keramični
kompoziti - Oznake in simboli (ISO 19634:2017)

Fine ceramics (advanced ceramics, advanced technical ceramics) - Ceramic composites

- Notations and symbols (ISO 19634:2017)
Hochleistungskeramik - Keramische Verbundwerkstoffe - Bezeichnungen und
Formelzeichen (ISO 19634:2017)
Céramiques techniques - Céramiques composites - Notations et symboles (ISO
19634:2017)
Ta slovenski standard je istoveten z: prEN ISO 19634
ICS:
01.075 Simboli za znake Character symbols
81.060.30 Sodobna keramika Advanced ceramics
oSIST prEN ISO 19634:2021 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 19634:2021
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oSIST prEN ISO 19634:2021
INTERNATIONAL ISO
STANDARD 19634
First edition
2017-10
Fine ceramics (advanced ceramics,
advanced technical ceramics) —
Ceramic composites — Notations and
symbols
Céramiques techniques — Céramiques composites — Notations et
symboles
Reference number
ISO 19634:2017(E)
ISO 2017
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oSIST prEN ISO 19634:2021
ISO 19634:2017(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2017, Published in Switzerland

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
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. [phone]
Fax [phone]
[e-mail]
www.iso.org
ii © ISO 2017 – All rights reserved
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oSIST prEN ISO 19634:2021
ISO 19634:2017(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Symbols .......................................................................................................................................................................................................................... 4

5 Significance and use .......................................................................................................................................................................................12

5.1 Significance .............................................................................................................................................................................................12

5.2 Use ..................................................................................................................................................................................................................12

Bibliography .............................................................................................................................................................................................................................13

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oSIST prEN ISO 19634:2021
ISO 19634:2017(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 (see 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 (see 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.

For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to the

World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following

URL: www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 206, Fine ceramics.
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oSIST prEN ISO 19634:2021
INTERNATIONAL STANDARD ISO 19634:2017(E)
Fine ceramics (advanced ceramics, advanced technical
ceramics) — Ceramic composites — Notations and symbols
1 Scope

This document defines the symbols to be used to represent physical, mechanical and thermal

characteristics, as determined by methods described in relevant ISO publications, for ceramic matrix

composites. It is aimed at avoiding confusion in reporting measurements and characteristics of

products.

Where possible, the definitions are in accordance with the relevant parts of ISO 80000. In addition, the

symbols used in undertaking measurements of these characteristics are also defined.

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 80000-4, Quantities and units — Part 4: Mechanics
ISO 80000-5, Quantities and units — Part 5: Thermodynamics
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 80000-4 and ISO 80000-5 and

the following apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
3.1
ceramic matrix composite

ceramic, carbon or glass matrix containing reinforcement distributed in one or more spatial directions

Note 1 to entry: Composites with continuous reinforcements constitute a specific class of these materials. Several

subclasses of ceramic matrix composites with continuous reinforcements can be distinguished.

3.2
nomenclature
The symbol F/I/M applies usually to ceramic matrix composites:

— F indicates the chemical nature of fibrous reinforcement: C stands for carbon, SiC for silicon carbide,

Al O for alumina, etc.
2 3

— I indicates the chemical nature of fibre/matrix interphase: C stands for carbon, BN for boron nitride,

LaPO for monazite, etc.

— M indicates the chemical nature of matrix: C for carbon, SiC for silicon carbide, Al O for alumina.

2 3

EXAMPLE 1 A ceramic matrix composite composed of a silicon carbide fibre, a carbon interphase and a silicon

carbide matrix is denoted by SiC/C/SiC.
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Note 1 to entry: More complex symbols can be used to describe the constituents with a greater degree of

precision.

EXAMPLE 2 For a composite composed of a carbon fibre, a multi-layered interphase of four alternate layers of

carbon and silicon carbide, and a silicon carbide matrix, the symbol is: C /[C/SiC] /SiC .

f 4 m
3.3
unidirectional ceramic matrix composite
1D material

ceramic matrix composite (3.1), the reinforcement of which is distributed in one single direction

Note 1 to entry: See Figure 1.
Key
1 direction of reinforcement

2 direction of the greater transverse dimension (width), perpendicular to direction 1

3 direction of the smaller transverse dimension (thickness), perpendicular to direction 1

NOTE When the width and the thickness are equal, then directions 2 and 3 are equivalent and can be chosen freely.

Figure 1 — Schematic diagram of a 1D material
3.4
in-plane reinforced ceramic matrix composite
2D material

ceramic matrix composite (3.1), where the reinforcements are placed along at least two directions in a

single plane
Note 1 to entry: See Figure 2.
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oSIST prEN ISO 19634:2021
ISO 19634:2017(E)
Key
1 direction of the greater fraction of reinforcement

2 direction perpendicular to direction 1 in the plane of reinforcement (not necessarily a direction of

reinforcement)
3 direction perpendicular to the plane of reinforcement

NOTE Strictly more than one direction of fibrous reinforcement, all contained within one plane [in the present

case, three directions of reinforcement in plane (1,2)].

When several directions have an equal fraction of reinforcement, it shall be stated which direction is chosen

as direction 1 in relation to the reinforcement structure (for example, orthogonal reinforced fabric: warp in

direction 1, weft in direction 2).
Figure 2 — Schematic diagram of a 2D material
3.5
multidirectional ceramic matrix composite
xD (2 < × ≤3) material

ceramic matrix composite (3.1), where the reinforcement is spatially distributed in at least three

directions not in a single plane
Note 1 to entry: See Figures 3 and 4.
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oSIST prEN ISO 19634:2021
ISO 19634:2017(E)
Figure 3 — Schematic diagram of a xD (2 < × ≤ 3) material
Key
1 direction of the greater fraction of reinforcement
2 direction perpendicular to direction 1
3 direction perpendicular to the plane containing directions 1 and 2

When several directions have equal fraction of reinforcement, it shall be stated which direction is chosen as direction

1, in relation to the reinforcement structure. When it is possible to define a plane of reinforcement, direction 2 will

be chosen in this plane perpendicular to direction 1 (direction 2 is not necessarily a direction of reinforcement), and

direction 3 will be perpendicular to the plane containing directions 1 and 2. When it is not possible to define a plane

of reinforcement, direction 2 is chosen arbitrarily, but perpendicular to direction 1 and shall be clearly identified.

Figure 4 — Schematic diagram of a 3D material
4 Symbols

The symbols used for the various mechanical and thermal quantities are given in Tables 1 to 4.

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Table 1 — Symbols related to physical quantities
Quantity Symbol Definition Unit Remark
Density ρ Ratio of the mass of a body to its volume kg/m
Apparent density ρ Ratio of the mass of the body to its total volume kg/m

Bulk density ρ Ratio of the mass of the dry material of a po- kg/m Bulk volume = sum of volumes of solid ma-

rous body to its volume terial, open pores and closed pores
Ratio of the mass of a multifilament tow to
Linear density t tex Tex is the mass in grams per 1 000 m
its length
Porosity P Ratio of the total volume of pores in a porous —
body to its total volume
Apparent porosity P Ratio of the volume of open pores to total —
volume
Mass m Quantity of matter in a body g
Phase volume fraction V Fractional volume of phase of type j de- —
f,j
termined from micrographs of poli
...