ISO/PRF 28401
(Main)Light metals and their alloys — Titanium and titanium alloys — Vocabulary
Light metals and their alloys — Titanium and titanium alloys — Vocabulary
This document defines terms and definitions related to titanium and titanium alloys.
Titre manque
General Information
Relations
Buy Standard
Standards Content (Sample)
International
Standard
ISO 28401
Second edition
Light metals and their alloys —
Titanium and titanium alloys —
Vocabulary
PROOF/ÉPREUVE
Reference number
ISO 28401:2024(en) © ISO 2024
ISO 28401:2024(en)
© ISO 2024
All rights reserved. Unless otherwise specified, or required in the context of its implementation, 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
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
PROOF/ÉPREUVE
ii
ISO 28401:2024(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 Material .1
3.2 Classification of phases and related terms .2
3.3 Classification of microstructure by morphology and related terms.2
3.4 Unwrought products .3
3.5 Wrought products.4
3.6 Castings .6
3.7 Methods of processing and treatment .7
3.8 Surface condition .9
3.9 Applications.10
3.10 Types of titanium materials and related terms.10
3.11 Titanium grades and compounds .11
Annex A (normative) Dividing line between unalloyed titanium and titanium alloys .12
Bibliography . 14
Index .15
PROOF/ÉPREUVE
iii
ISO 28401:2024(en)
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 document 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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of 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 www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC79, Light metals and their alloys, Subcommittee
SC 11, Titanium.
This second edition cancels and replaces the first edition (ISO 28401:2010), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— the title was changed from “Classification and terminology” to “Vocabulary”;
— new terms were added;
— some sentences were revised for clarity;
— the notations alpha and beta were changed from English to Greek;
— some abbreviated terms were removed;
— Annex A was revised and tables were added as additional normative text;
— Annex B was removed.
A list of all parts in the ISO 28401 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
PROOF/ÉPREUVE
iv
ISO 28401:2024(en)
Introduction
There are many technical terms related to titanium used in national standards.
Unifying and interpreting these technical terms worldwide, so that specifications can be understood
accurately around the world, is essential for international trade in common titanium products.
There is a need to classify technical terms related to titanium and establish a common interpretation of
each term.
PROOF/ÉPREUVE
v
International Standard ISO 28401:2024(en)
Light metals and their alloys — Titanium and titanium alloys
— Vocabulary
1 Scope
This document defines terms and definitions related to titanium and titanium alloys.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
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 Material
3.1.1
titanium sponge
products of metallic titanium in a porous and sponge-like form, which are applied as titanium metal
melting stock
Note 1 to entry: To produce titanium sponge, oxidized titanium ore is chlorinated to tetrachloride and is condensed
and purified. Then the product is reduced with magnesium or sodium under an inert atmosphere.
3.1.2
alloy
metallic substance consisting of a mixture of the basic metallic element and other elements, such as alloying
elements and impurities
Note 1 to entry: In this document, the most predominant element by mass fraction is titanium.
3.1.3
alloying element
metallic or non-metallic elements intentionally added to, or retained by, base metal to give special properties
3.1.4
impurity
metallic or non-metallic elements which are present but not intentionally added to, or retained by, a metal
3.1.5
wrought alloy
alloy primarily intended for the production of wrought products by hot and/or cold plastic forming
3.1.6
casting alloy
alloy primarily intended for the production of castings
PROOF/ÉPREUVE
ISO 28401:2024(en)
3.1.7
master alloy
alloy intended for alloying elements added to molten or compacted titanium by controlling physical
properties such as melting point, densities and dissolvability
3.1.8
heat-treatable alloy
alloy capable of being strengthened by a suitable thermal treatment
3.1.9
non-heat-treatable alloy
alloy capable of being strengthened only by cold working rather than by thermal treatment
3.2 Classification of phases and related terms
3.2.1
α phase
solid solution at low temperature with a hexagonal closed packed crystal structure
3.2.2
α phase stabilisers
alloy elements such as aluminium, oxygen, nitrogen and carbon that expand the α phase, which is the low
temperature phase of titanium alloy, to high temperature and enhance the stability of the α structure
3.2.3
β phase
solid solution at high temperature with a body centred cubic crystal structure
3.2.4
β phase stabilisers
alloy elements such as iron, manganese, molybdenum and vanadium that expand the β phase, which is the
high temperature phase of titanium alloy, to low temperature and enhance the stability of the β structure
3.2.5
α plus β phase
mixture of the α and β phases
3.2.6
β-transus temperature
temperature above which the crystal structure turns to the β phase
3.3 Classification of microstructure by morphology and related terms
3.3.1
microstructure by morphology
microstructure observed by an optical and/or a scanning microscope characterized by composition,
processing and heat treating
Note 1 to entry: See Reference [2] for detailed classifications of titanium and titanium alloy microstructures, including
microstructure photographs.
3.3.2
equiaxed α structure
polygonal or globular α structure with approximately equal dimensions in all directions
Note 1 to entry: In some types of α-β titanium alloys, most α structures are observed in a globular rather than equiaxed
form. Therefore, this structure is sometimes called the globular α structure.
PROOF/ÉPREUVE
ISO 28401:2024(en)
3.3.3
acicular α structure
microstructure in which β transforms the selected crystal planes by nucleation and growth or martensitically
Note 1 to entry: This microstructure is also called the Widmansttäten α structure.
Note 2 to entry: Depending on the aspect ratio and the existence state in the colonies, other names for this
microstructure are platelet α structure, blocky α structure, basketweave α structure and lamellar α structure.
3.3.4
grain boundary α structure
α structure formed at prior β grain boundaries during cooling from the single β phase region
3.3.5
elongated α structure
grain microstructure in which the length of one of the three axial directions of the crystal grains is
remarkably elongated
Note 1 to entry: The structure shows that the influence of plastic working remains strong or that it has failed to
become equiaxed and remained elongated.
Note 2 to entry: The string-like elongated structure is sometimes called stringy α structure.
3.3.6
bimodal structure
microstructure composed of equiaxed or elongated α structure embedded in transformed β matrix
3.4 Unwrought products
3.4.1
unwrought product
general term for products obtained by either melting, casting or powder metallurgy processes or a
combination thereof
EXAMPLE Ingots for rolling, ingots for extruding, ingots for forging and ingots for remelting.
3.4.2
electrode for remelting
cylindrical or rectangular semi-product formed from titanium sponge and alloying elements or consolidated
from recycled and processed scrap, to be remelted once or multiple cycles in a vacuum or in inert gas for at
least the final melting
3.4.3
ingot for rolling, extruding and forging
titanium and titanium alloy ingot melted mostly using the vacuum arc remelting (VAR) method applied for
at least the final cycle in a vacuum or in inert gas, suitable for rolling, extruding and forging
Note 1 to entry: The melting method is not necessarily limited to VAR. It also includes cases that involve electron beam
melting (EBM), plasma arc melting (PAM) and others.
Note 2 to entry: The VAR method is the typical method used for melting titanium and titanium alloys. In this method,
the titanium or titanium alloy electrode is dissolved while being consumed itself by an arc generated between a
consumable electrode and a water-cooled copper crucible in a vacuum or in an inert ga
...
© ISO #### – All rights reserved
ISO/DIS28401:2024 (E)PRF 28401
ISO /TC 79/SC 11/WG 5
2024-04-22
Secretariat: JISC
Date: 2024-06-26
Light metals and their alloys — Titanium and titanium alloys —
Vocabulary
DIS stage
Warning for WDs and CDs
This document is not an ISO International Standard. It is distributed for review and comment. It is subject to
change without notice and may not be referred to as an International Standard.
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.
ISO #####-#:####(X)
2 © ISO #### – All rights reserved
ISO/DISPRF 28401:2024(Een)
Published in Switzerland
All rights reserved. Unless otherwise specified, or required in the context of its implementation, 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
CP 401 • Ch,. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel, Phone: + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail: copyright@iso,.org
Website: www.iso.org
Published in Switzerland
www,iso,org
© ISO #### 2024 – All rights reserved
iii
ISO/DISPRF 28401:2024 (E(en)
Contents
Foreword . v
Introduction . vii
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 Material . 1
3.2 Classification of phases and related terms . 2
3.3 Classification of microstructure by morphology and related terms . 2
3.4 Unwrought products . 3
3.5 Wrought products . 4
3.6 Castings . 7
3.7 Methods of processing and treatment . 8
3.8 Surface condition . 10
3.9 Applications . 11
3.10 Types of titanium materials and related terms . 11
3.11 Titanium grades and compounds . 12
Annex A (normative) Dividing line between unalloyed titanium and titanium alloys . 13
Bibliography . 15
Index 18
Foreword . iv
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 Material . 1
3.2 Classification of phases and related terms . 2
3.3 Classification of microstructure by morphology and related terms . 2
3.4 Unwrought products . 3
3.5 Wrought products . 4
3.6 Castings . 7
3.7 Methods of processing and treatment . 8
3.8 Surface condition . 10
3.9 Applications . 11
3.10 Types of titanium materials and related terms . 11
3.11 Titanium grades and compounds . 12
Annex A (normative) Dividing line between unalloyed titanium and titanium alloys . 13
Bibliography . 15
Alphabetical index . 16
iv © ISO #### – All rights reserved
ISO/DISPRF 28401:2024(Een)
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 document 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).www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights
in respect thereof. As of the date of publication of this document, ISO had not received notice of (a) patent(s)
which may be required to implement this document. However, implementers are cautioned that this may not
represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents.www.iso.org/patents. ISO shall not be held responsible for identifying any or all such
patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of 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
www.iso.org/iso/foreword.htmlwww.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC79, Light metals and their alloys, Subcommittee
SC 11, Titanium.
This second edition cancels and replaces the first edition (ISO 28401:2010), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— — the title was changed from “Classification and terminology” to “Vocabulary”;
— — new terms were added;
— — some sentences were revised for clarity;
— — the notations alpha and beta were changed from English to Greek;
— — some abbreviated terms were removed;
— — Annex AAnnex A was revised and tables were added as additional normative text;
— — Annex B was removed.
A list of all parts in the ISO 28401 series can be found on the ISO website.
© ISO #### 2024 – All rights reserved
v
ISO/DISPRF 28401:2024 (E(en)
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.htmlwww.iso.org/members.html.
vi © ISO #### – All rights reserved
ISO/DISPRF 28401:2024(Een)
Introduction
There are many technical terms related to titanium used in national standards.
Unifying and interpreting these technical terms worldwide, so that specifications can be understood
accurately around the world, is essential for international trade in common titanium products.
There is a need to classify technical terms related to titanium and establish a common interpretation of each
term.
© ISO #### 2024 – All rights reserved
vii
ISO/DISPRF 28401:2024(Een)
Light metals and their alloys — Titanium and titanium alloys —
Vocabulary
1 Scope
This document defines terms and definitions related to titanium and titanium alloys.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— — ISO Online browsing platform: available at https://www.iso.org/obphttps://www.iso.org/obp
— — IEC Electropedia: available at http://www.electropedia.org/https://www.electropedia.org/
3.1 Material
3.1.1
titanium sponge
products of metallic titanium in a porous and sponge-like form, which are applied as titanium metal melting
stock
Note 1 to entry: To produce titanium sponge, oxidized titanium ore is chlorinated to tetrachloride and is condensed
and purified. Then the product is reduced with magnesium or sodium under an inert atmosphere.
3.1.2
alloy
metallic substance consisting of a mixture of the basic metallic element and other elements, such as alloying
elements and impurities
Note 1 to entry: In this document, the most predominant element by mass fraction is titanium.
3.1.3
alloying element
metallic or non-metallic elements intentionally added to, or retained by, base metal to give special properties
3.1.4
impurity
metallic or non-metallic elements which are present but not intentionally added to, or retained by, a metal
3.1.5
wrought alloy
alloy primarily intended for the production of wrought products by hot and/or cold plastic forming
3.1.6
casting alloy
alloy primarily intended for the production of castings
© ISO #### 2024 – All rights reserved
ISO/DISPRF 28401:2024 (E(en)
3.1.7
master alloy
alloy intended for alloying elements added to molten or compacted titanium by controlling physical properties
such as melting point, densities and dissolvability
3.1.8.
heat-treatable alloy
alloy capable of being strengthened by a suitable thermal treatment
3.1.9
non-heat-treatable alloy
alloy capable of being strengthened only by cold working rather than by thermal treatment
3.2 Classification of phases and related terms
3.2.1
α phase
solid solution at low temperature with a hexagonal closed packed crystal structure
3.2.2
α phase stabilisers
alloy elements such as aluminium, oxygen, nitrogen and carbon that expand the α phase, which is the low
temperature phase of titanium alloy, to high temperature and enhance the stability of the α structure
3.2.3
β phase
solid solution at high temperature with a body centred cubic crystal structure
3.2.4
β phase stabilisers
alloy elements such as iron, manganese, molybdenum and vanadium that expand the β phase, which is the
high temperature phase of titanium alloy, to low temperature and enhance the stability of the β structure
3.2.5
α plus β phase
mixture of the α and β phases
3.2.6
β-transus temperature
temperature above which the crystal structure turns to the β phase
3.3 Classification of microstructure by morphology and related terms
3.3.1
microstructure by morphology
microstructure observed by an optical and/or a scanning microscope characterized by c
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.