SIST EN ISO 4957:2000

SLOVENSKI STANDARD
SIST EN ISO 4957:2000
01-november-2000
Orodna jekla (ISO 4957:1999)
Tool steels (ISO 4957:1999)
Werkzeugstähle (ISO 4957:1999)
Aciers a outils (ISO 4957:1999)
Ta slovenski standard je istoveten z: EN ISO 4957:1999
ICS:
77.140.35 Orodna jekla Tool steels
SIST EN ISO 4957:2000 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 4957:2000

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SIST EN ISO 4957:2000

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SIST EN ISO 4957:2000

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SIST EN ISO 4957:2000
INTERNATIONAL ISO
STANDARD 4957
Second edition
1999-12-15
Tool steels
Aciers à outils
Reference number
ISO 4957:1999(E)
©
ISO 1999

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SIST EN ISO 4957:2000
ISO 4957:1999(E)
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ii © ISO 1999 – All rights reserved

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SIST EN ISO 4957:2000
ISO 4957:1999(E)
Contents
1 Scope .1
2 Normative references .1
3 Terms and definitions .2
4 Requirements.3
5 Inspection, testing and conformance of products.4
6 Marking .5
7 Ordering and designation .5
Annex A (informative) Hardness-tempering temperature-curves .18
Annex B (normative) Supplementary or special requirements .28
Annex C (informative) Designations of comparable steels.30
Bibliography.32
© ISO 1999 – All rights reserved iii

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SIST EN ISO 4957:2000
ISO 4957:1999(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
Draft International Standards adopted by the technical committees are circulated to the member bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 4957 was prepared by Technical Committee ISO/TC 17, Steel, Subcommittee SC 4,
Heat treatable and alloy steels.
This second edition cancels and replaces the first edition (ISO 4957:1980) which has been technically revised.
Annex B forms a normative part of this International Standard, annexes A and C are for information only.
iv © ISO 1999 – All rights reserved

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SIST EN ISO 4957:2000
INTERNATIONAL STANDARD ISO 4957:1999(E)
Tool steels
1 Scope
1.1 This International Standard covers the following grades of wrought tool steels:
a) non-alloy cold-work tool steels;
b) alloy cold-work tool steels;
c) alloy hot-work tool steels;
d) high-speed tool steels.
If not stated otherwise, this International Standard applies to all types of hot-rolled, forged, cold-drawn or cold-rolled
products which are supplied in one of the surface and heat-treatment conditions given in 4.1.2 and Table 1.
Products according to this International Standard may be produced by powder metallurgy.
NOTE 1 The Tables 2, 4, 6 and 8 cover only those steels which have gained certain international importance, which does not
mean however, that they are available in all industrial countries. In addition, a number of other steels for tools are specified in
regional, national or company standards.
NOTE 2 Where the heat resistance of the tools is of particular importance, as for example in the case of tools for hot forming
glass, the material selection should be based on ISO 4955 or ISO 9722.
1.2 In addition to this International Standard, the general technical delivery requirements of ISO 404 are
applicable.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this International Standard. For dated references, subsequent amendments to, or revisions of, any of these
publications do not apply. However, parties to agreements based on this International Standard are encouraged to
investigate the possibility of applying the most recent editions of the normative documents indicated below. For
undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC
maintain registers of currently valid International Standards.
ISO 377:1997, Steel and steel products — Location and preparation of samples and test pieces for mechanical
testing.
ISO 404:1992, Steel and steel products — General technical delivery requirements.
ISO 1035-1:1980, Hot-rolled steel bars — Part 1: Dimensions of round bars.
ISO 1035-3:1980, Hot-rolled steel bars — Part 3: Dimensions of flat bars.
ISO 1035-4:1982, Hot-rolled steel bars — Part 4: Tolerances.
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SIST EN ISO 4957:2000
ISO 4957:1999(E)
ISO 4948-1:1982, Steels — Classification — Part 1: Classification of steels into unalloyed and alloy steels based
on chemical composition.
1)
ISO 6506:1981 , Metallic materials — Hardness test — Brinell test.
2)
ISO 6508:1986 ,Metallic materials— Hardness test—Rockwelltest(scalesA-B-C-D-E-F-G-H-K).
ISO 6929:1987, Steel products — Definitions and classification.
ISO/TR 9769:1991, Steel and iron — Review of available methods of analysis.
ISO 10474:1991, Steel and steel products — Inspection documents.
ISO 14284:1996, Steel and iron — Sampling and preparation of samples for the determination of chemical
composition.
3 Terms and definitions
For the purposes of this International Standard, the terms and definitions given in ISO 4948-1 and ISO 6829 as well
as the following apply.
3.1
product forms
[ISO 6929]
3.2
unalloyed and alloyed steel
[ISO 4948-1]
3.3
tool steels
special steels suitable for working or processing of materials, for handling and measuring workpieces and, for this
purpose, exhibiting high hardness and wear resistance and/or toughness
3.3.1
cold-work tool steels
non-alloy or alloy tool steels for applications in which the surface temperature is generally below 200 °C
3.3.2
hot-work tool steels
alloy tool steels for applications in which the surface temperature is generally over 200 °C
3.3.3
high-speed tool steels
steels used mainly for machining and for forming processes and which, because of their chemical composition,
have the highest high-temperature hardness and temper resistance up to about 600 °C
1) To be replaced by ISO 6506-1, ISO 6506-2 and ISO 6506-3.
2) To be replaced by ISO 6508-1, ISO 6508-2 and ISO 6508-3.
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SIST EN ISO 4957:2000
ISO 4957:1999(E)
4 Requirements
4.1 Manufacturing process
4.1.1 General
The manufacturing process of the steel and the products is left to the discretion of the manufacturer, with the
restrictions given in 4.1.2.
When he so requests, the purchaser shall be informed what steel making process is being used.
4.1.2 Heat-treatment condition and surface condition on delivery
The heat-treatment and surface conditions of the products shall comply with the agreements when ordering.
4.1.2.1 Heat-treatment condition
The heat-treatment conditions are given in Table 1.
Unless otherwise specified in the order, the tool steels (except C45U, Table 2, 35CrMo7, X38CrMo16 and
40CrMnNiMo8-6-4, Table 4, 55NiCrMoV7, Table 6) are delivered in the annealed condition.
4.1.2.2 Surface condition
Usual surface conditions are:
a) the hot-rolled or forged condition ( = as hot worked);
b) the machined (ground, polished, turned, peeled or milled) condition;
c) the cold-reduced condition.
4.2 Chemical composition and mechanical properties
4.2.1 Table 1 gives a survey of combinations of usual heat-treatment conditions at delivery and requirements
according to Tables 2 to 9 (chemical composition, hardness).
4.2.2 For hardness-tempering temperature-curves of the steels see annex A.
4.2.3 For hardness penetration depth of non-alloy cold-work tool steels, see Table 2, footnote d.
4.3 Surface quality
4.3.1 All products shall have a workmanlike finish and shall be clean and free from surface imperfections likely to
have an adverse effect on their processing or designated application.
4.3.2 Ground, polished or finished-machined products shall be free from surface imperfections and surface
decarburization.
4.3.3 Hot-rolled, forged, cold-drawn or rough-machined products shall be ordered with sufficient material to be
removed from all surfaces by machining or grinding to allow for
a) surface decarburization and
b) surface imperfections.
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SIST EN ISO 4957:2000
ISO 4957:1999(E)
As long as no International Standard for the machining allowances of tool steels is available, the allowances shall
be agreed at the time of enquiry and order.
4.4 Shape, dimensions and tolerances
The shape, dimensions and tolerances of the products shall comply with the requirements agreed upon at the time
of enquiry and order. The agreements shall, as far as possible, be based on corresponding International Standards
or otherwise, on suitable national standards.
For rolled flat and round bars, the following International Standards cover dimensions and/or tolerances for
products included in this International Standard: ISO 1035-1, ISO 1035-3 and ISO 1035-4.
NOTE By agreement, the tolerances can be all plus or other disposition than equal plus/minus.
5 Inspection, testing and conformance of products
5.1 Inspection and testing procedures and types of inspection documents
5.1.1 For each delivery, the issue of any inspection document in accordance with ISO 10474 may be agreed
upon at the time of enquiry and order.
5.1.2 If, in accordance with the agreements made at the time of enquiry and order, a test report is to be provided,
this shall cover:
a) the statement that the material complies with the requirements of the order;
b) the results of the cast analysis for all elements specified for the type of steel supplied.
5.1.3 If, in accordance with the agreements in the order, an inspection certificate 3.1.A, 3.1.B or 3.1.C or an
inspection report 3.2 (see ISO 10474) is to be provided, the specific inspections and tests described in 5.2 shall be
carried out and their results shall be certified in the document.
In addition the document shall cover
a) the results of the cast analysis provided by the manufacturer for all elements specified for the steel type
concerned;
b) the results of all inspections and tests ordered by supplementary requirements (see annex B);
c) the symbol letters of numbers connecting the inspection documents, the test pieces and products to each
other.
5.2 Specific inspection and testing
5.2.1 Number of sample products
5.2.1.1 Chemical composition
The cast analysis is given by the manufacturer. For product analysis see B.2 in annex B.
5.2.1.2 Mechanical properties
One sample product per test unit shall be tested.
5.2.1.2.1 For material delivered in the annealed or annealed and cold rolled or annealed and cold drawn
condition, the test unit shall consist of products from the same cast and the same heat-treatment batch.
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SIST EN ISO 4957:2000
ISO 4957:1999(E)
In the case of material heat treated in a continuous furnace, a heat-treatment batch is regarded as that quantity of
products (of the same cast and dimensions) which without any interruptions, was under constant treatment
conditions (same furnace temperature, atmosphere and transportation speed) through the furnace.
5.2.1.2.2 For material delivered in the quenched and tempered condition, the test unit shall consist of products
from the same cast, heat-treatment and thickness.
However, if the manufacturer verifies that the thickness has no significant effect on the hardness in the quenched
and tempered condition, then different thicknesses may be covered in a test unit.
5.2.1.3 Inspection of the surface quality
Unless otherwise agreed when ordering (see B.5), the number of products to be inspected for surface quality is left
to the discretion of the inspector.
5.2.1.4 Dimensional inspection
Unless otherwise agreed when ordering (see B.6) the number of products to be inspected for their shape and
dimensions is left to the discretion of the inspector.
5.2.2 Sampling
5.2.2.1 The general conditions for selection and preparation of samples and test pieces shall be in accordance
with ISO 377 and ISO 14284.
5.2.2.2 For the Brinell hardness test the surface of the sample product or of a test piece taken from the sample
product in the delivery condition shall be prepared in accordance with the requirements of ISO 6506.
5.2.3 Test methods
5.2.3.1 The Brinell hardness test shall be made in accordance with ISO 6506.
5.2.3.2 Unless otherwise agreed (see B.5), the surface quality shall be inspected visually.
5.2.4 Retests
For retests, ISO 404 shall apply.
6 Marking
The manufacturer shall mark the products or the bundles or boxes containing the products in a suitable way, so
that the i
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