Magnetic materials - Part 8-6: Specifications for individual materials - Soft magnetic metallic materials

IEC 60404-8-6:2016 specifies the general requirements, magnetic properties, geometric characteristics and tolerances as well as inspection procedures for pure iron, silicon-iron, nickel-iron and cobalt-iron. The materials are in the form of bar, billet, sheet, strip or wire. The alloys covered correspond to those defined by classes A, C1, C2, E1 to E4 and F1 to F3 in IEC 60404-1. This edition includes the following significant technical changes with respect to the previous edition: Removal of Table 2b).

Matériaux magnétiques - Partie 8-6: Spécifications pour matériaux particuliers - Matériaux métalliques magnétiquement doux

L’IEC 60404-8-6:2016 spécifie les exigences générales, les propriétés magnétiques, les caractéristiques géométriques et leurs tolérances, ainsi que les modes de contrôle pour le fer pur, le fer-silicium, le fer-nickel et le fer-cobalt. Les matériaux se présentent sous forme de barres, billettes, tôles, bandes ou fils. Les alliages concernés correspondent à ceux définis par les classes A, C1, C2, E1 à E4 et F1 à F3 de l’IEC 60404-1. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente: Suppression du Tableau 2b).

General Information

Status
Published
Publication Date
07-Dec-2016
Current Stage
PPUB - Publication issued
Completion Date
08-Dec-2016
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IEC 60404-8-6
Edition 3.0 2016-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Magnetic materials –
Part 8-6: Specifications for individual materials – Soft magnetic metallic
materials
Matériaux magnétiques –
Partie 8-6: Spécifications pour matériaux particuliers – Matériaux métalliques
magnétiquement doux
IEC 60404-8-6:2016-12(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 60404-8-6
Edition 3.0 2016-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Magnetic materials –
Part 8-6: Specifications for individual materials – Soft magnetic metallic
materials
Matériaux magnétiques –
Partie 8-6: Spécifications pour matériaux particuliers – Matériaux métalliques
magnétiquement doux
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.030 ISBN 978-2-8322-3674-1

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – IEC 60404-8-6:2016 © IEC 2016
CONTENTS

FOREWORD ........................................................................................................................... 4

1 Scope .............................................................................................................................. 6

2 Normative references ...................................................................................................... 6

3 Terms, definitions and abbreviations ............................................................................... 7

3.1 Terms and definitions .............................................................................................. 7

3.2 Abbreviations for test specimens ............................................................................ 8

4 Classification ................................................................................................................... 8

4.1 General ................................................................................................................... 8

4.2 Alloy class A (irons) ................................................................................................ 9

4.3 Alloy class C (silicon steels).................................................................................... 9

4.4 Alloy class E (nickel-iron alloys) .............................................................................. 9

4.5 Alloy class F (cobalt-iron alloys) ............................................................................. 9

5 Designation ..................................................................................................................... 9

6 General requirements ...................................................................................................... 9

6.1 Chemical composition and production process ........................................................ 9

6.2 Delivery condition ................................................................................................. 10

6.2.1 General ......................................................................................................... 10

6.2.2 Form of supply ............................................................................................... 10

6.2.3 Surface condition ........................................................................................... 10

7 Technical requirements ................................................................................................. 10

7.1 Magnetic properties .............................................................................................. 10

7.2 Geometric characteristics and tolerances .............................................................. 11

7.2.1 Flat products: sheet, plate and strip ............................................................... 11

7.2.2 Cold-worked bar, rod and wire ....................................................................... 11

7.2.3 Hot-finished bar ............................................................................................. 11

8 Inspection and testing .................................................................................................... 11

8.1 General ................................................................................................................. 11

8.2 Selection of samples ............................................................................................. 12

8.2.1 General ......................................................................................................... 12

8.2.2 Flat products ................................................................................................. 12

8.2.3 Long products ................................................................................................ 12

8.2.4 Wire............................................................................................................... 12

8.3 Magnetic properties .............................................................................................. 12

8.3.1 Magnetic testing, DC measurements .............................................................. 12

8.3.2 Magnetic testing, AC measurements .............................................................. 12

8.3.3 Test specimens ............................................................................................. 12

8.4 Geometric characteristics and tolerances .............................................................. 12

8.4.1 Thickness of flat products .............................................................................. 12

8.4.2 Width of flat products ..................................................................................... 12

8.4.3 Flatness ........................................................................................................ 12

8.4.4 Edge camber ................................................................................................. 13

8.4.5 Dimensions of long products .......................................................................... 13

8.4.6 Straightness of long products ........................................................................ 13

8.5 Retests ................................................................................................................. 13

9 Complaints .................................................................................................................... 13

10 Ordering information ...................................................................................................... 13

---------------------- Page: 4 ----------------------
IEC 60404-8-6:2016 © IEC 2016 – 3 –

11 Certification ................................................................................................................... 13

Bibliography .......................................................................................................................... 20

Table 1 – Chemical composition of the alloy classes in accordance with IEC 60404-1 .......... 14

Table 2 – Minimum amplitude permeability requirements for sheet and strip – AC

measurement (50 Hz or 60 Hz), sine flux conditions, thickness 0,05 mm to 0,38 mm ............ 15

Table 3 – DC magnetic property requirements for bar, billet, rod, sheet, strip and wire,

thickness or diameter greater than 0,05 mm – S.R., L.R. or E.S. specimen ........................... 16

Table 4 – Maximum permeability rise factor for sheet and strip – L.R. test specimen,

AC measurement (50 Hz or 60 Hz) ....................................................................................... 17

Table 5 – Dimensional requirements for toroidal strip-wound cores ....................................... 17

Table 6 – Tolerances on thickness of cold-rolled sheet and strip ........................................... 18

Table 7 – Tolerances on width of sheet and strip .................................................................. 18

Table 8 – Tolerances on dimensions of cold-worked bar, rod and wire .................................. 19

---------------------- Page: 5 ----------------------
– 4 – IEC 60404-8-6:2016 © IEC 2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MAGNETIC MATERIALS –
Part 8-6: Specifications for individual materials –
Soft magnetic metallic materials
FOREWORD

1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

all national electrotechnical committees (IEC National Committees). The object of IEC is to promote

international co-operation on all questions concerning standardization in the electrical and electronic fields. To

this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,

Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC

Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested

in the subject dealt with may participate in this preparatory work. International, governmental and non-

governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely

with the International Organization for Standardization (ISO) in accordance with conditions determined by

agreement between the two organizations.

2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international

consensus of opinion on the relevant subjects since each technical committee has representation from all

interested IEC National Committees.

3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

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Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

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5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

services carried out by independent certification bodies.

6) All users should ensure that they have the latest edition of this publication.

7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and

members of its technical committees and IEC National Committees for any personal injury, property damage or

other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and

expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC

Publications.

8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

indispensable for the correct application of this publication.

9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of

patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

International Standard IEC 60404-8-6 has been prepared by IEC technical committee 68:

Magnetic alloys and steels.
This third edition cancels and replaces the second edition published in 1999 and
Amendment 1:2007. This edition constitutes a technical revision.

This edition includes the following significant technical changes with respect to the previous

edition:
Removal of Table 2b).
---------------------- Page: 6 ----------------------
IEC 60404-8-6:2016 © IEC 2016 – 5 –
The text of this standard is based on the following documents:
CDV Report on voting
68/528/CDV 68/552/RVC

Full information on the voting for the approval of this International Standard can be found in

the report on voting indicated in the above table.

This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

A list of all parts in the IEC 60404 series, published under the general title Magnetic

materials, can be found on the IEC website.

The committee has decided that the contents of this publication will remain unchanged until

the stability date indicated on the IEC website under "http://webstore.iec.ch" in the data

related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
---------------------- Page: 7 ----------------------
– 6 – IEC 60404-8-6:2016 © IEC 2016
MAGNETIC MATERIALS –
Part 8-6: Specifications for individual materials –
Soft magnetic metallic materials
1 Scope

This part of IEC 60404 specifies the general requirements, magnetic properties, geometric

characteristics and tolerances as well as inspection procedures for pure iron, silicon-iron,

nickel-iron and cobalt-iron. The materials are in the form of bar, billet, sheet, strip or wire. The

alloys covered correspond to those defined by classes A, C1, C2, E1 to E4 and F1 to F3 in

IEC 60404-1.

Magnetic materials used primarily for relays, iron and steel products, classified only by

coercivity, are covered in IEC 60404-8-10. IEC 60404-8-10 is less restrictive in terms of

magnetic properties than the irons (class A) and the silicon steels (classes C21 and C22)

specified in this standard, but it gives more comprehensive dimensional tolerances.

Non-oriented and oriented silicon steels (C21 and C22) for industrial power frequency

applications, classified by specific total loss, are covered in IEC 60404-8-3, IEC 60404-8-4

and IEC 60404-8-7.

Non-oriented and oriented thin magnetic materials for use at medium frequencies, classified

by specific total loss, are covered in IEC 60404-8-8.
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.

IEC 60050-121, International Electrotechnical Vocabulary – Part 121: Electromagnetism

IEC 60050-131, International Electrotechnical Vocabulary – Part 131: Circuit theory

IEC 60050-221, International Electrotechnical Vocabulary – Chapter 221: Magnetic materials

and components
IEC 60404-1, Magnetic materials – Part 1: Classification
IEC 60404-2, Magnetic materials – Part 2: Methods of measurement of the magnetic
properties of electrical steel sheet and strip by means of an Epstein frame

IEC 60404-4, Magnetic materials – Part 4: Methods of measurement of d.c. magnetic

properties of iron and steel
IEC 60404-6, Magnetic materials – Part 6: Methods of measurement of the magnetic

properties of magnetically soft metallic and powder materials at frequencies in the range

20 Hz to 200 kHz by the use of ring specimens
---------------------- Page: 8 ----------------------
IEC 60404-8-6:2016 © IEC 2016 – 7 –

IEC 60404-7, Magnetic materials – Part 7: Method of measurement of the coercivity of

magnetic materials in an open magnetic circuit

IEC 60404-8-3, Magnetic materials − Part 8-3: Specifications for individual materials − Cold-

rolled electrical non-alloyed and alloyed steel sheet and strip delivered in the semi-processed

state

IEC 60404-8-4, Magnetic materials – Part 8-4: Specifications for individual materials – Cold-

rolled non-oriented electrical steel strip and sheet delivered in the fully-processed state

IEC 60404-8-7, Magnetic materials – Part 8-7: Specifications for individual materials – Cold-

rolled grain-oriented electrical steel strip and sheet delivered in the fully-processed state

IEC 60404-8-8, Magnetic materials – Part 8: Specifications for individual materials –

Section 8: Specification for thin magnetic steel strip for use at medium frequencies

IEC 60404-8-10, Magnetic materials – Part 8-10: Specifications for individual materials –

Magnetic materials (iron and steel) for use in relays

IEC 60404-9, Magnetic materials – Part 9: Methods of determination of the geometrical

characteristics of magnetic steel sheet and strip
IEC 60635, Toroidal strip-wound cores made of magnetically soft material
ISO 404, Steel and steel products – General technical delivery requirements
ISO 10474, Steel and steel products – Inspection documents
3 Terms, definitions and abbreviations
3.1 Terms and definitions

For the purpose of this document, the terms and definitions given in IEC 60050-121,

IEC 60050-131, IEC 60050-221 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 http://www.iso.org/obp
3.1.1
bar
solid product of uniform cross-section supplied in straight lengths

Note 1 to entry: The cross-section can be round, square, rectangular or regular polygonal.

Note 2 to entry: Flat: A bar of rectangular cross-section, rolled on the four faces, whose thickness is generally

5 mm or greater and whose width is not greater than 150 mm.

Note 3 to entry: Round: A bar of circular cross-section whose diameter is generally 8 mm or greater.

3.1.2
billet

solid product of uniform cross-section, which may be square, round or rectangular, with a

width less than twice the thickness
---------------------- Page: 9 ----------------------
– 8 – IEC 60404-8-6:2016 © IEC 2016
3.1.3
heat

product of a furnace melt or of a number of melts that are mixed prior to casting

3.1.4
lot

material from the same heat, of the same form, produced at the same time and, if annealed,

heat-treated together or sequentially in a continuous furnace
3.1.5
rod

cold-drawn product of uniform rectangular or round cross-section, supplied in straight lengths

3.1.6
sheet and plate

flat-rolled product of uniform cross-section, supplied in coils or cut lengths where the width is

over 600 mm

Note 1 to entry: Sheets have a thickness under 5 mm and plates have a thickness over 5 mm.

3.1.7
straightness of long products
greatest distance between the bar and the line joining the two ends of the bar
3.1.8
strip

flat-rolled product of uniform cross-section, supplied in coils or cut lengths where the width is

under 600 mm and the thickness under 5 mm
3.1.9
wire

rolled or drawn product of uniform round or rectangular cross-section, supplied in coils

3.2 Abbreviations for test specimens

Type E.S.: Elongated specimen for test samples, of circular, rectangular or polygonal cross-

section, with a length to diameter ratio of at least 5/1, according to IEC 60404-7.

Type L.R.: Laminated rings stamped or etched from flat products (for magnetic head ring, a

core with 10 mm outside diameter and 6 mm inside diameter can be used).

Type S.R.: Solid rings or square frames, formed or machined from solid material. The outside

diameter of the ring shall be between 30 mm and 50 mm, with an outside/inside diameter ratio

from 1,2 to 1,4.
NOTE Types L.R. and S.R. are only applicable to essentially isotropic materials.

Type S.W.: Strip-wound cores as defined by IEC 60635. For dimensional restrictions, see

Table 5. The outside diameters of test cores are between 30 mm and 80 mm.
4 Classification
4.1 General

The materials covered by this document are classified according to the main alloying element

and the content of this element. The subclassification takes into account the different uses of

the alloys.
---------------------- Page: 10 ----------------------
IEC 60404-8-6:2016 © IEC 2016 – 9 –
4.2 Alloy class A (irons)
This material is classified according to the maximum value of coercivity.
4.3 Alloy class C (silicon steels)

Alloy C1, in which the main alloying element is silicon with a content up to approximately 5 %

, is classified according to the maximum value of coercivity.

Alloys C2, in which the main alloying element is silicon with a content up to approximately

5 %, are classified according to the shape of the hysteresis loop and the minimum amplitude

permeability in an AC measurement (50 Hz or 60 Hz) with a L.R. specimen made of material

with a thickness of 0,35 mm; the measuring point is H = 1,6 A/m.
4.4 Alloy class E (nickel-iron alloys)

These alloys are classified according to the shape of the hysteresis loop and the minimum

amplitude permeability in an AC measurement (50 Hz or 60 Hz), under sine flux conditions,

with a S.W. specimen made of material with a thickness of 0,10 mm.
4.5 Alloy class F (cobalt-iron alloys)

These alloys are classified according to the shape of the hysteresis loop and to the maximum

value of coercivity.
5 Designation

The conventional designation of the materials comprises the following in the order given:

a) the letter for the alloy class: A, C, E or F (see Table 1);

b) the number according to the content of the main alloying element (see Table 1);

c) for alloy classes C, E and F, the number 1 or 2 according to the shape of the hysteresis

loop:
1) = round (non-oriented)
2) = rectangular (oriented by texture or by thermomagnetic treatment);
d) a dash;

e) depending on the alloy class, either the maximum value for the coercivity in amperes per

metre or the peak value of the minimum permeability divided by 1 000 for a given

magnetic field strength ( H = 0,4 A/m or 1,6 A/m) and a given thickness measured with a

certain test specimen (see above under classification).
EXAMPLE:

E31-10: nickel-iron with 40 % to 51 % weight of nickel, a round hysteresis loop, and a minimum amplitude

permeability of 10 000 at the peak value of the magnetic field strength H of 0,4 A/m at 50 Hz or 60 Hz for a strip-

wound core made of a sheet with a thickness of 0,10 mm.
6 General requirements
6.1 Chemical composition and production process

The typical composition of each of the alloy classes covered by this document is given in

Table 1.

The actual composition and production process are left to the discretion of the manufacturer,

unless otherwise agreed between the manufacturer and purchaser, and specified in the order.

---------------------- Page: 11 ----------------------
– 10 – IEC 60404-8-6:2016 © IEC 2016
6.2 Delivery condition
6.2.1 General

The materials covered by this standard may be delivered in the hot-finished, cold-worked or

annealed condition. The condition required shall be specified in the order.
6.2.2 Form of supply
Coils shall be of constant width and wound in such a manner that the edges are

superimposed in a regular manner and the side faces of the coil are substantially flat. Coils

shall be sufficiently tightly wound that they do not collapse under their own weight.

Coils can occasionally present welds or interleaves resulting from the removal of defective

zones, subject to prior agreement between the parties. The value of the additional thickness

due to the weld is subject to special agreement. If necessary, the marking of welds or

interleaves may form the subject of a special agreement. For coils containing repair welds or

interleaves, each part of the strip shall be of the same quality material.

The edges of parts welded together shall not be so much out of alignment as to affect the

further processing of the material.
The mass of coils shall be agreed upon at the time of ordering.
6.2.3 Surface condition

The surface condition of sheets or strips shall be uniform, clean, and free from grease and

rust.

Isolated imperfections such as scratches, blisters, etc. may be tolerated if the thickne

...

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