INTERNATIONAL
STANDARD

ISO
683-4
Second edition
2016-07- 15

Heat-treatable steels, alloy steels and
free-cutting steels —

Part 4:

Free-cutting steels
Aciers pour traitement thermique, aciers alliés et aciers pour
décolletage —
Partie 4: Aciers pour décolletage

Reference number
ISO 683-4:2016(E)
© ISO 2016


ISO 683-4:2016(E)

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ii

© ISO 2016 – All rights reserved


ISO 683-4:2016(E)

Page

Contents

Foreword ........................................................................................................................................................................................................................................ iv
1
2

3
4


Scope ................................................................................................................................................................................................................................. 1
Normative references ...................................................................................................................................................................................... 1

Terms and definitions ..................................................................................................................................................................................... 2
Classification and designation ............................................................................................................................................................... 2
4. 1

4.2
5

............................................................................................................................................................................................. 2
Designation ................................................................................................................................................................................................ 2
C las s ificatio n

Information to be supplied by the purchaser......................................................................................................................... 2

................................................................................................................................................................... 2
.................................................................................................... 3
5.3 Ordering example ................................................................................................................................................................................. 3
6
Manufacturing process .................................................................................................................................................................................. 3
6.1 General ........................................................................................................................................................................................................... 3
.................................................................................................... 3
f
................................................................................................................................ 3
6.2.2 Particular heat-treatment condition............................................................................................................... 3
..................................................................................................................................................................... 3
f
7
Requirements .......................................................................................................................................................................................................... 4

7.1 Chemical composition, hardness, and mechanical properties ...................................................................... 4
7.1.1 General...................................................................................................................................................................................... 4
7.1.2 Chemical composition ................................................................................................................................................. 4
7.1.3 Mechanical properties ................................................................................................................................................ 4
............................................................................................................................................................................................ 4
.................................................................................................................................................................................................. 4
7.4 Grain size ...................................................................................................................................................................................................... 4
7.5 Internal soundness .............................................................................................................................................................................. 4
......................................................................................................................................................................................... 5
f
7.7 Shape, dimensions, and tolerances ........................................................................................................................................ 5
8
Inspection .................................................................................................................................................................................................................... 5
................................................................................................................ 5
f
f
........................................................................................................................................................................... 6
.................................................................................................................................................. 6
.............................................................. 6
f
8.3.2 Visual and dimensional inspection .................................................................................................................. 6
9
Test methods ............................................................................................................................................................................................................. 6
.................................................................................................................................................................................. 6
9.2 Hardness and mechanical tests ................................................................................................................................................ 6
9.2.1 Hardness ................................................................................................................................................................................. 6
9.2.2 Mechanical tests ............................................................................................................................................................... 6
9.3 Retests ............................................................................................................................................................................................................ 6
10
Marking .......................................................................................................................................................................................................................... 7

Annex A (normative) Ruling sections for mechanical properties ....................................................................................... 14
Annex B (normative) Supplementary or special requirements ............................................................................................ 17
5 .1

M andato ry in fo rmatio n

5 .2

O p tio ns /s up p lementary o r s p ecial requirements

6.2

H eat treatment and s ur ace co nditio n at delivery
6.2 .1

N o rmal co nditio n at delivery

6.3

Traceab ility o

7.2

M achinab ility

7.3

Weldab ility

7.6


S ur ace quality

8.1

Tes ting p ro cedures and typ es o

8.2

Frequency o

8.3

S p ecific ins p ectio n and tes ting
8.3 .1

9.1

the cas t

do cuments

tes ting

Verificatio n o

the hardnes s and mechanical p ro p erties

C hemical analys is


(informative)

Annex C
Designation of steels given in this part of ISO 683 and of comparable
grades covered in various designation systems ................................................................................................................ 19

(informative)

Annex D
Dimensional standards applicable to products complying with this
part of ISO 683 ..................................................................................................................................................................................................... 20
Bibliography ............................................................................................................................................................................................................................. 21

© ISO 2016 – All rights reserved

iii


ISO 683-4:2016(E)

Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work o f 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 o f

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
di fferent types o f ISO documents should be noted. This document was dra fted 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 o f the elements o f this document may be the subject o f
patent rights. ISO shall not be held responsible for identi fying any or all such patent rights. Details o f
any patent rights identified during the development o f 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 in formation given for the convenience o f users and does not

constitute an endorsement.

For an explanation on the meaning o f ISO specific terms and expressions related to con formity 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.
The committee responsible for this document is ISO/TC 17, Steel, Subcommittee SC 4, Heat treatable and
alloy steels.
This second edition cancels and replaces the first edition (ISO 683-4:2014), o f which it constitutes a

minor revision.
ISO 683 consists of the following parts, under the general title Heat-treatable steels, alloy steels and freecutting steels:
— Part 1: Non-alloy steels for quenching and tempering
— Part 2: Alloy steels for quenching and tempering
— Part 3: Case-hardening steels
— Part 4: Free-cutting steels
— Part 5: Nitriding steels

— Part 14: Hot-rolled steels for quenched and tempered springs
— Part 15: Valve steels for internal combustion engines
— Part 17: Ball and roller bearing steels
— Part 18: Bright steel products

iv

© ISO 2016 – All rights reserved


INTERNATIONAL STANDARD

ISO 683-4:2016(E)

Heat-treatable steels, alloy steels and free-cutting steels —

Part 4:

Free-cutting steels
1 Scope
This part of ISO 683
f
billets, slabs), bars and wire rod, manufactured from the free-cutting steels listed in Table 2 and supplied
f
f
ff
f
Table 1, rows 2 to 4.
This part of ISO 683 covers three groups of free-cutting steels for mechanical purposes as listed in
Table 2

a) not intended for heat treatment,
b) suitable for case-hardening, and
c) suitable for quenching and tempering.
Free-cutting steels are often used as bright bars. For these products, refer to ISO 683-18.
gives the te ch nic al del iver y re qui rements

i n one o

the tre atment condition s given

or the d i

erent typ e s o

or s em i-fi ni she d pro duc ts (e . g. blo om s ,

pro duc ts i n

, namely

I n s p e c i a l c a s e s , va ri ation s i n the s e te ch n ic a l del iver y re qui rements or add ition s to them c an
s ubj e c t o f an agre ement at the ti me o f enqui r y and order (s e e

5.2 and Annex B).

form

the

I n add ition to th i s p ar t o f I S O 6 8 3 , the genera l te ch n ic a l del iver y re qu i rements o f I S O 4 0 4 are appl ic able .


2 Normative references
T he

fol lowi ng

i nd i s p en s able

do c u ments , i n whole or i n p ar t, are normatively re ference d i n th i s do c u ment a nd are

for

its

appl ic ation .

For date d re ference s ,

on ly the

e d ition

cite d appl ie s .

For u ndate d

re ference s , the late s t e d ition o f the re ference d do c u ment (i nclud i ng any amend ments) appl ie s .

ISO 377, Steel and steel products — Location and preparation ofsamples and test pieces for mechanical testing
ISO 404, Steel and steel products — General technical delivery requirements

ISO 643, Steels — Micrographic determination of the apparent grain size
ISO 4885, Ferrous products — Heat treatments — Vocabulary
ISO 4948-1, Steels  —  Classification  —  Part  1:  Classification  of  steels  into  unalloyed  and  alloy  steels  based 
on chemical composition

ISO 4948-2, Steels  —  Classification  —  Part  2:  Classification  of  unalloyed  and  alloy  steels  according  to  main 
quality classes and main property or application characteristics

ISO 6506-1, Metallic materials — Brinell hardness test — Part 1: Test method
ISO 6892-1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature
ISO 6929, Steel products — Vocabulary
ISO 9443, Heat-treatable and alloy steels — Surface quality classes for hot-rolled round bars and wire
rods — Technical delivery conditions

© ISO 2016 – All rights reserved

1


ISO 683-4:2016(E)

ISO 10474, Steel and steel products — Inspection documents
ISO 14284, Steel and iron — Sampling and preparation of samples for the determination of chemical

composition

ISO/TR 9769, Steel and iron — Review of available methods of analysis
ISO/TS 4949, Steel names based on letter symbols
3 Terms and definitions


For the purposes o f this document, the terms and definitions given in ISO 377, ISO 4885, ISO 4948-1,
ISO 4948-2, ISO 6929, ISO 14284 and the following apply.
3.1
ruling section

section for which the specified mechanical properties shall apply
Note 1 to entry: Independent o f the actual shape and dimensions o f the cross-section o f the product, the size o f its
ruling section is always given by a diameter. This corresponds to the diameter o f an “equivalent round bar”. That

is a round bar which will show the same cooling rate as the actual ruling section of the product concerned at its
position for taking the test pieces, when being cooled from austenitizing temperature.
3.2
free-cutting steels

steels characterized by good machinability with high metal removal rate, mostly obtained by higher

than normal contents of sulphur

Note 1 to entry: Other elements besides sul fur can be added for further improving the machinability.

4 Classification and designation
4.1 Classification

The classification o f the relevant steel grades is allocated in accordance with ISO 4948-1 and ISO 4948-2.
All steels covered by this part o f ISO 683 are classified as non-alloy quality steels.
4.2

Designation

For the steel grades covered by this part o f ISO 683, the steel names given in the relevant tables are


allocated in accordance with ISO/TS 4949.
5
5.1

Information to be supplied by the purchaser
Mandatory information

The manu facturer shall obtain the following in formation from the purchaser at the time o f enquiry

and order:

a) the quantity to be delivered;
b) the designation o f the product form (e.g. slab, bloom, billet, round bar, wire rod);

c) either the designation of the dimensional standard and the dimensions and tolerances selected from
this (see 7.7 ) or the designation of the drawing or any other document, covering the dimensions
and tolerances required for the product;

d) a re ference to this part o f ISO 683, i.e. ISO 683-4;
2

© ISO 2016 – All rights reserved


ISO 683-4:2016(E)

e) the designation of the steel grade given in Table 2 ;
f


) standard designation for a test report 2.2 or, i f required, any other type o f inspection document in

accordance with ISO 10474.

5.2 Options/supplementary or special requirements
A number o f options are specified in this part o f ISO 683 and listed below. I f the purchaser does not
indicate the wish to implement any o f these options, the products will be supplied in accordance with
the basic specification o f this part o f ISO 683 (see 5.1).
a) I f a heat-treatment condition other than the untreated condition is required, the symbol for this

other condition (see Table 1, column 2).

b) Any supplementary requirement that shall comply with the symbol and, where necessary, the
details o f this supplementary requirement (see Annex B).

c) Suitability o f bars and rod for bright drawing (see 7.6.4).

d) Any requirement relating to removal o f sur face de fects (see 7.6.5).

5.3 Ordering example
EXAMPLE 50 hot-rolled round bars according to ISO 1035-1, with a nominal diameter of 40 mm and a
nominal length of 8 000 mm, with diameter tolerance according to class S and with length tolerance according to
ISO 1035-4, class L2, made of steel grade ISO 683-4, 35S20 (see Table 2) in the heat-treatment condition +U (see
Table 1), product analysis/option (see B.5) with a test report 2.2 in accordance with ISO 10474.
50 round bars ISO 1035 – 40,0S × 8 000L2
steel grade ISO 683-4 – 35S20 option B.5
Inspection document ISO 10474 – 2.2

6 Manufacturing process
6.1 General

The manu facturing process o f the steel and o f the products is, with the restrictions given by the

requirements in 6.2 and 6.3, left to the discretion of the manufacturer.
For minimum reduction ratio or minimum thickness deformation ratio of rolled and forged products,
see B.6.
6.2 Heat treatment and surface condition at delivery
6.2.1 Normal condition at delivery

Unless otherwise agreed at the time o f enquiry and order, the products shall be delivered in the
untreated condition that means “as hot-worked”.

6.2.2 Particular heat-treatment condition
I f so agreed at the time o f enquiry and order, the products shall be delivered in one o f the particular

heat-treatment conditions given in Table 1, rows 3 and 4.
6.3 Traceability of the cast

Each product shall be traceable to the cast (see Clause 10).
© ISO 2016 – All rights reserved

3


ISO 683-4:2016(E)

7 Requirements
7.1
7.1.1

Chemical composition, hardness, and mechanical properties

General

Table 1
f
f
f
requirements according to Tables 2 to 6 (chemical composition, maximum hardness, mechanical
properties).
give s a s ur vey o

7.1.2

combi nation s o

u s ua l tre atment cond ition s at del iver y, pro duc t

orm s , and

Chemical composition

T he chem ic a l comp o s ition de term i ne d b y c a s t a na lys i s sh a l l comply with the va lue s i n

Perm i s s ible devi ation s b e twe en the l i m iti ng va lue s

are given in Table 3.

for

c as t ana lys i s and the va lue s


for

Table 2.
pro duc t ana lys i s

T he pro duc t ana lys i s s ha l l b e c a rrie d out when s p e c i fie d at the ti me o f the enqu i r y and order (s e e

B.5).

WARNING — Due to hazardous effects to health and environmental problems of Pb, it is
recommended to instead use steels only with sulfur and other innocuous free-cutting element
additions.
7.1.3

Mechanical properties

Mechanical properties for free-cutting steels are given in Tables 4 to 6.
7.2

Machinability

T he s te el s covere d b y th i s p ar t o f I S O 6 8 3 have go o d mach i nabi l ity a nd ch ip -bre a ki ng ch arac teri s tics .
However, the mach i nabi l ity de cre as e s with i nc re a s i ng c arb on, s i l icon and mangane s e contents , wh i le
cold re duc tion i mprove s the mach i nabi l ity o f the s te el s no t i ntende d

for he at tre atment a nd

NO TE

genera l ly


N o n-le ade d

s te el s

with

comp a rab le

chem ic a l

co mp o s ition

h ave

s te el 10 S2 0 .

identic a l

me ch a n ic a l

pro p er tie s , but o ften lower m ach i n ab i l ity th a n le ade d s te el s .

7.3

Weldability

B e c au s e o f thei r h igh s u l fur and pho s phor us content,

for welding.


fre e - c utti ng s te el s

are norma l ly no t re com mende d

7.4 Grain size
Un le s s o ther wi s e agre e d at the ti me o f enqu i r y and order, the gra i n s i ze sh a l l b e le ft to the d i s c re tion o f
the ma nu fac turer. I f a fi ne grai n s tr uc tu re i s re qu i re d

for

c a s e -h arden i ng s te el s or s te el s

and tempering, the special requirement in B.3 shall be ordered.
I f d i re c t harden i ng tre atment i s u s e d

7.5

for c a s e -h arden i ng s te el s ,

for

quench i ng

a fi ne gra i n s tr uc tu re s hou ld b e ordere d .

Internal soundness

Where appropriate, requirements relating to the internal soundness of the products shall be agreed at
B.4).


the ti me o f enqu i r y a nd order (s e e

4

© ISO 2016 – All rights reserved


ISO 683-4:2016(E)

7.6 Surface quality
7.6.1

applied.

All products shall have a smooth surface finish appropriate to the manufacturing processes

Minor surface imperfections, which can occur under normal manufacturing conditions, such as
prints originating from rolled-in scale, are not to be regarded as defects.
7.6.2
7.6.3

Bars and wire rod are delivered with surface class 1za2 according to ISO 9443, unless otherwise

agreed at the time o f enquiry and order.

It is more di fficult to detect and eliminate sur face discontinuities in coiled products than in cut lengths.
This should be taken into account when agreements on sur face quality are made.
I f suitability o f bars and rod for bright drawing is required, this shall be agreed at the time o f
enquiry and order.

7.6.4
7.6.5

The removal o f surface de fects by welding is not permitted.

If surface discontinuities are repaired, the method and maximum depth of removal shall be agreed at

the time o f enquiry and order.
7.7

Shape, dimensions, and tolerances

The shape, dimensions, and tolerances o f the products shall comply with the requirements agreed at
the time o f enquiry and order. The agreements shall, as much as possible, be based on corresponding

International Standards (see Annex D), or otherwise on suitable national standards.
8 Inspection
8.1

Testing procedures and types of documents

Products complying with this part o f ISO 683 shall be ordered and delivered with one o f the
inspection documents specified in ISO 10474. The type o f document shall be agreed upon at the time
o f enquiry and order. I f the order does not contain any specification o f this type, a test report 2.2 shall
8.1.1

be issued.
8.1.2

I f, in accordance with the agreements made at the time o f enquiry and order, a test report 2.2 is


to be provided, this shall cover the following information:

a) confirmation that the material complies with the requirements o f the order;
b) results o f the cast analysis o f the concerned cast for all elements specified in

steel grade.

Table 2 for the

I f in accordance with the agreements in the order an inspection certificate 3.1 or 3.2 is to be
provided, the specific inspections and tests described in 8.2, 8.3, and Clause 9 shall be carried out and the
results shall be confirmed in the inspection certificate.

8.1.3

In addition, the inspection certificate shall cover the following:
a) confirmation that the material complies with the requirements o f the order;
b) results o f the cast analysis o f the concerned cast for all elements specified in
steel grade;

© ISO 2016 – All rights reserved

Table 2 for the
5


ISO 683-4:2016(E)
c) the result o f all inspections and tests ordered by supplementary requirements (see Annex B );
d) the symbol letters or numbers relating the inspection certificate, test pieces and products to


each other.

8.2 Frequency of testing
The amount o f testing, the sampling conditions, and the test methods to be applied for the verification

of compliance with the requirements shall be in accordance with the prescriptions of Table 7.
8.3 Specific inspection and testing
8.3.1

Verification o f the hardness and mechanical properties

The hardness requirements and/or mechanical properties given for the relevant treatment condition
in Table 1 , column 6, sub-column 6.2, shall be verified, with the following exception. The requirements
given in Table 1 , footnote a (mechanical properties of reference test pieces), shall only be verified i f the
supplementary requirement given in B.2, is ordered.
8.3.2 Visual and dimensional inspection
A su fficient number o f products shall be inspected to ensure compliance with the specification.

9 Test methods
9.1 Chemical analysis
The choice o f a suitable physical or chemical analytical method for the analysis shall be at the discretion
o f the manu facturer. In cases o f dispute, the method for product analysis used shall be agreed taking

into account the relevant existing International Standards.

The list o f available International Standards on chemical analysis is given in ISO/TR 9769.

9.2 Hardness and mechanical tests
9.2.1 Hardness


For products in the untreated condition, the hardness shall be measured in accordance with ISO 6506-1.
9.2.2 Mechanical tests

The tensile test shall be carried out in accordance with ISO 6892-1.
For the specified yield strength in the tables o f mechanical properties in this part o f ISO 683, the upper
yield strength (ReH ) shall be determined.
I f a yield phenomenon is not present, the 0,2 % proo f strength (Rp0,2 ) shall be determined.

9.3 Retests
Retests for steels for quenching and tempering and criteria are specified in ISO 404.

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© ISO 2016 – All rights reserved


ISO 683-4:2016(E)

10 Marking

The manufacturer shall mark the products or the bundles or boxes containing the products in a suitable
way, so that the identification o f the cast, the steel name, and the origin o f the delivery is possible
(see B.7).
Table 1 — Combinations of usual heat-treatment conditions at delivery, product forms, and
requirements according to Tables 2 to 6

1
2


3
4

1

2

Heattreatment
condition

3

4

5

6

x = applicable for
Applicable requirements
SemiBars Wire rod 6.1
6.2
finished
at delivery
products
Untreated None
x
x
x
Chemical Maximum Brinell hardness or

or +U
composition (in the case of dispute) the
according to tensile strength according to
Tables 2 and 3 Table 4 in the case of steels
not intended for heat
treatment or Table 5 in the
case of case-hardening steels
or Table 6 in the case of steels
for quenching and temperinga
Quenched +QT
—
x
—
Mechanical properties
and
according to Table 6 in the
tempered
case of steels for quenching
and tempering
Others Other treatment conditions, for example, the stress relieved condition, can be agreed at the
Symbol

time o f enquiry and order.

a The mechanical properties specified in Table 6 for the quenched + tempered
appropriate heat treatment i f so agreed at the time o f enquiry and order (see B.2).

condition shall be achievable after

Table 2 — Steel grades and chemical composition (cast analysis)

Steel name

9S20
11SMn30
11SMnPb30
11SMn37
11SMnPb37
10S20
10SPb20

% mass fraction a
C

Si

Mn

P

Steels not intended for heat treatment
0,13
0,05 b
0,60 to 1,20 0,11dc
0,14
0,05 b
0,90 to 1,30 0,11 c
0,14
0,07 to 0,13

0,05 b

1,00 to 1,50
Case-hardening steels
0,40
0,70 to 1,10

S

Pb

0,11 c

0,15 to 0,25
—
0,27 to 0,33 0,20 —
to 0,35
—
0,34 to 0,40 0,20 to 0,35

0,060

0,15 to 0,25 0,20 —
to 0,35

NOTE Elements not quoted shall not be intentionally added to the steel without the agreement o f the purchaser, other
than for the purpose o f finishing the heat. All reasonable precautions shall be taken to prevent the addition o f such elements
from scrap or other materials used in manu facture which a ffect the mechanical properties and applicability. However, i f
agreed, the manu facturer can add elements such as Ca, Se, Te, etc. for the purpose o f improving the machinability. These

elements have to be reported in the inspection document.
a Maximum values unless otherwise indicated.


b Since silicon has an adverse e ffect on machinability, it is not intentionally added to specified limits, but i f the formation
o f special oxides is guaranteed, a Si-content o f 0,10 % to 0,40 % can be agreed.
c At the time o f enquiry and order, it can be agreed that either a grade with 0,06 % to 0,11 % P or a grade with max,
0,05 % P shall be delivered.

© ISO 2016 – All rights reserved

7


ISO 683-4:2016(E)

Table 2 (continued)

% mass fraction a

Steel name

C

15SMn13
17SMn20

Si

Mn

P


0,12 to 0,18
0,40
0,90 to 1,30 0,060
0,14 to 0,20
0,40
1,20 to 1,60 0,060
Steels for quenching and tempering
0,32 to 0,39
0,40
0,70 to 1,10 0,060

35S20
35SPb20
36SMn14
36SMnPb14
35SMn20
35SMnPb20
38SMn28
38SMnPb28
44SMn28
44SMnPb28
46S20
46SPb20

0,32 to 0,39

0,40

1,30 to 1,70


0,060

0,32 to 0,39

0,40

0,90 to 1,40

0,060

0,35 to 0,40

0,40

1,20 to 1,50

0,060

0,40 to 0,48

0,40

1,30 to 1,70

0,060

0,42 to 0,50

0,40


0,70 to 1,10

0,060

S

0,08 to 0,18
0,15 to 0,25

Pb

—
—

0,15 to 0,25 0,15 —
to 0,35
—
0,10 to 0,18 0,15 to 0,35
0,15 to 0,25 0,15 —
to 0,35
0,24 to 0,33 0,15 —
to 0,35
0,24 to 0,33 0,15 —
to 0,35
0,15 to 0,25 0,15 —
to 0,35

NOTE Elements not quoted shall not be intentionally added to the steel without the agreement o f the purchaser, other
than for the purpose o f finishing the heat. All reasonable precautions shall be taken to prevent the addition o f such elements
from scrap or other materials used in manu facture which a ffect the mechanical properties and applicability. However, i f

agreed, the manu facturer can add elements such as Ca, Se, Te, etc. for the purpose o f improving the machinability. These

elements have to be reported in the inspection document.
a Maximum values unless otherwise indicated.

b Since silicon has an adverse e ffect on machinability, it is not intentionally added to specified limits, but i f the formation
o f special oxides is guaranteed, a Si-content o f 0,10 % to 0,40 % can be agreed.
c At the time o f enquiry and order, it can be agreed that either a grade with 0,06 % to 0,11 % P or a grade with max,
0,05 % P shall be delivered.
Table 3 — Permissible deviations between the product analysis and the limiting values for the
cast analysis
Element

C
Si
Mn
P
S
Pb

Permissible maximum content
according to cast analysis

Permissible deviations a

% mass fraction
≤0,30
0,30 < C ≤ 0,50
≤0,05
0,05 < Si ≤ 0,40

≤1,00
1,00 < Mn ≤ 1,70
≤0,06
0,06 < P ≤ 0,11
≤0,33
0,33 < S ≤ 0,40

% mass fraction

≤0,35

−0,02

±0,02
±0,03
±0,01
±0,03
±0,04
±0,06
±0,008
±0,02
±0,03
±0,04
+0,03

a ± means that, in one cast, the deviation can occur over the upper value or under the lower
value o f the specified range in this table, but not both at the same time.
8

© ISO 2016 – All rights reserved



ISO 683-4:2016(E)
Table 4 — Mechanical properties of free-cutting steels not intended for heat treatment
Steel name b

Diameter

Hardness a

mm

HBW max.
154
154
154
140
169
169
169
169
154

d ≤ 16

9S20

16 < d ≤ 4 0
40 < d ≤ 63
6 3 < d ≤ 10 0


11SMn30
11SMnPb30
11SMn37
11SMnPb37
a
b

5 ≤ d ≤ 10
10 < d ≤ 16
16 < d ≤ 4 0
40 < d ≤ 63
6 3 < d ≤ 10 0

Untreated
Tensile strength
Rm

MPa
330 to 520
330 to 520
320 to 520
310 to 470
380 to 570
380 to 570
380 to 570
370 to 570
360 to 520

In cases of dispute, the tensile strength values are the decisive factor.

I n th i s tab le , g rade s a l lo ye d wi th

fu r ther

e le me nts

fo r

b e tte r m ach i n ab i l i t y a re no t

e x p l ic itl y me ntio ne d , b ut the me ch a n ic a l p ro p er tie s a re a l s o va l id

fo r

the m (s e e

Table 2).

Table 5 — Mechanical properties of case-hardening free-cutting steels
Steel name b

Untreated
Tensile strength
Hardness a

Diameter

mm

HBW max

156
156
156
156
146
181
178
178
172
160
181
178
178
172
160

5 ≤ d ≤ 10

10S20
10SPb20

10 < d ≤ 16
16 < d ≤ 4 0
40 < d ≤ 63
6 3 < d ≤ 10 0
5 ≤ d ≤ 10

15SMn13

10 < d ≤ 16

16 < d ≤ 4 0
40 < d ≤ 63
6 3 < d ≤ 10 0
5 ≤ d ≤ 10

17SMn20

10 < d ≤ 16
16 < d ≤ 4 0
40 < d ≤ 63
6 3 < d ≤ 10 0

a
b

Rm

MPa
360 to 530
360 to 530
360 to 530
360 to 530
350 to 490
430 to 610
430 to 600
430 to 600
430 to 580
420 to 540
430 to 610
430 to 600

430 to 600
430 to 580
420 to 540

In cases of dispute, the tensile strength values are the decisive factor.
In

th i s

tab le ,

g rade s

a l lo ye d

wi th

fu r ther

e le ments

fo r

b e tter

e x p l ic i tl y me ntio ne d , b ut the me ch a n ic a l p ro p e r tie s a re a l s o va l id

© ISO 2016 – All rights reserved

fo r


m ach i n ab i l it y a re
them (s e e

Table 2).

no t

9


ISO 683-4:2016(E)
Table 6 — Mechanical properties of free-cutting steels for quenching and tempering
Steel name b

Diameter

mm
5 ≤ d ≤ 10

35S20
35SPb20

10 < d ≤ 16
16 < d ≤ 4 0
40 < d ≤ 63
6 3 < d ≤ 10 0
5 ≤ d ≤ 10

36SMn14

36SMnPb14

10 < d ≤ 16
16 < d ≤ 4 0
40 < d ≤ 63
6 3 < d ≤ 10 0
5 ≤ d ≤ 10

35SMn20
35SMnPb20

10 < d ≤ 16
16 < d ≤ 4 0
40 < d ≤ 63
6 3 < d ≤ 10 0
5 ≤ d ≤ 10

38SMn28
38SMnPb28

10 < d ≤ 16
16 < d ≤ 4 0
40 < d ≤ 63
6 3 < d ≤ 10 0
5 ≤ d ≤ 10

44SMn28
44SMnPb28

10 < d ≤ 16

16 < d ≤ 4 0
40 < d ≤ 63
6 3 < d ≤ 10 0
5 ≤ d ≤ 10

46S20
46SPb20

10 < d ≤ 16
16 < d ≤ 4 0
40 < d ≤ 63
6 3 < d ≤ 10 0

a
b

Untreated
Tensile
Hardness a
strength

HBW max.
210
204
198
196
190
225
225
219

216
216
225
225
219
216
216
228
219
213
213
204
(266)
(252)
241
231
228
234
228
222
213
207

Rm

MPa
550 to 720
550 to 700
520 to 680
520 to 670

500 to 650
580 to 770
580 to 770
560 to 750
560 to 740
550 to 740
580 to 770
580 to 770
560 to 750
560 to 740
550 to 740
580 to 780
580 to 750
560 to 730
560 to 730
550 to 700
630 to 900
630 to 850
630 to 820
620 to 790
610 to 780
590 to 800
590 to 780
590 to 760
580 to 730
560 to 710

In cases of dispute, the tensile strength values are the decisive factor.
I n th i s tab le , g rade s a l lo ye d wi th


fu r ther

e le ments

fo r

mechanical properties are also valid for them (see Table 2).

10

Quenched and tempered
Tensile properties
Re min

MPa
430
430
380
320
320
480
460
420
400
360
—
420
365
335
—

480
460
420
400
380
520
480
420
410
400
490
490
430
370
370

Rm

MPa
630 to 780
630 to 780
600 to 750
550 to 700
550 to 700
700 to 850
700 to 850
670 to 820
640 to 790
570 to 720
—

620 to 820
590 to 790
540 to 740
—
700 to 850
700 to 850
700 to 850
700 to 850
630 to 800
700 to 850
700 to 850
700 to 850
700 to 850
700 to 850
700 to 850
700 to 850
650 to 800
630 to 780
630 to 780

A min
%

15
15
16
17
17
14
14

15
16
17
—
14
16
17
—
15
15
15
16
16
16
16
16
16
16
12
12
13
14
14

b e tter m ach i n ab i l i ty a re no t e x p l ic i tl y me ntio ne d , b ut the

© ISO 2016 – All rights reserved


ISO 683-4:2016(E)


T

a

b

l

e



7



—



T
e

s

t


c


o

n

d

i

t

i

o

n

s

f



o

1
No.




v
e

r

i

2

Requirements

f
i

c

a

t

3

i

o

n




o

f


c

o

m

p

l

4

i

a

n

c

e



w


i

t

h



t

h

e



v

a

r

i

o

u

s




r

e

q

u

i

r

e

m

e

n

t

s

5

6


Samplingb

Test method

Amount of testing
Sample
Tests
products
per
per test sample
unit
product

See
tables

Test
unit a

1 Chemical
composition
2 Hardness
in the
untreated
condition
(as rolled)

Tables 2
and 3

Tables 4,
5, and 6

C
C+D

1

1

3 Mechanical
properties
of products
in the
untreated
or quenched
and
tempered
condition

Tables 4,
5, and 6

C+D
+T

1c

1


NO TE

a

r

( T he c a s t a n a l ys i s i s gi ven b y the m a nu fac tu rer;

B.5)
The hardness shall
be measured, if
possible, at the
circumference of the
product at a distance
of 1 × diameter from
one end and, in cases
of products with
square or rectangular
cross-section, at a
distance of 0,25 × w
(width of the product)
from one longitudinal
edge. In cases of
dispute, the tensile
test is to be done.
The test pieces for
the tensile test shall
be taken in
accordance with
Figure 1.

a n a l ys i s , s e e

fo r

p ro duc t

According to
ISO 6506-1

The tensile test
shall be carried out
in accordance with
ISO 6892-1 on
proportional test
pieces having a
gauge length of
0
(S0 = area of the
cross-section of the
test piece.)
L 0 = 5 , 6 5 √S

Ver i fic atio n o f the re qu i reme nts i s o n l y ne ce s s a r y i f a n i n s p e c tio n cer ti fic ate i s o rde re d .

T he te s ts s h a l l b e c a r r ie d o ut s ep a rate l y

fo r

e ach c a s t a s i nd ic ate d b y “C ”, e ach d i me n s io n a s i nd ic ate d b y “D ”, a nd e ach


he at- tre atme nt b atch a s i nd ic ate d b y “T ”.

Products with different thicknesses can be grouped if the thicknesses lie in the same dimensional range for mechanical
properties and if the differences in thickness do not affect the properties. In case of doubt, the thinnest and the thickest
product shall be tested.
b The general conditions for selection and preparation of test samples and test pieces shall be in accordance with ISO 377
and ISO 14284.
c

I f the p ro duc ts a re co nti nuo u s l y he at tre ate d , o ne s a mp le p ro duc t s h a l l b e ta ke n

least one sample product for each cast.

© ISO 2016 – All rights reserved

fo r

e ach 2 5 t o r p a r t, the re o f, b ut at

11


ISO 683-4:2016(E)

Table 8 — Conditions for heat treatment of case-hardening free-cutting steels a

Steel name e

Carburizing
temperature b


°C

10S20
10SPb20
15SMn13
17SMn20

Corehardening
temperature

Casehardening
temperature

Quenching
agent

830 to 870

880 to 920

780 to 820

Water, oil,
emulsionc

°C

880 to 980


Double hardening

Direct and
simple
hardening
temperature

°C

Temperingd

°C

°C
150 to 200

The temperatures given for carburizing, direct and simple hardening, core hardening, case hardening, and tempering

a

a re

fo r

g u id a nce; the ac tu a l temp eratu re s cho s e n s h a l l b e tho s e th at wi l l g i ve the p ro p er tie s re qu i re d .

The carburizing temperature will depend on the chemical composition of the steel, the mass of the product, and the
carburizing medium. If the steels are direct hardened, in general a temperature of 950 °C is not exceeded. For special
procedures, for example under vacuum, higher temperatures, for example 1 020 °C to 1 050 °C, are not unusual.


b
c

T he ki nd o f que nch i ng agent de p e nd s ,

of

d
e

fu r n ace

fo r e xa mp le ,

o n the s h ap e o f the p ro duc ts , the co o l i n g co nd itio n s a nd the qu a nti t y

fi l l i n g.

Time for tempering as a guide: 1 h minimum.

I n th i s tab le , g rade s a l lo ye d wi th

fu r the r

e le ments

fo r

treatment conditions are also valid for them (see Table 2).


b e tter m ach i n ab i l it y a re no t e xp l ic i tl y mentio ne d , b ut the he at-

Table 9 — Conditions for heat treatment of free-cutting steels for quenching and temperinga
Quenchingb

Steel name d

35S20
35SPb20
36SMn14
36SMnPb14
35SMn20
35SMnPb20
38SMn28
38SMnPb28
44SMn28
44SMnPb28
46S20
46SPb20

Temperingc

°C
860 to 890

Water or oil

°C
540 to 680


850 to 880

Water or oil

540 to 680

840 to 870

Water or oil

540 to 680

Medium

The temperature are for guidance, but the actual temperatures chosen shall be those that
will give the properties required.
b Time for austenitizing as a guide: 0,5 h minimum.
c Time for tempering as a guide: 1 h minimum.
a

d

In

th i s

tab le ,

g rade s


a l lo ye d

wi th

fu r the r

e leme nts

fo r

b e tter

e x p l ic i tl y me ntio ne d , b ut the he at- tre atme nt co nd itio n s a re a l s o va l id

12

m ach i n ab i l it y

fo r

the m (s e e

a re

no t

Table 2).

© ISO 2016 – All rights reserved



ISO 683-4:2016(E)

Dimensions in millimetres

1

a

2

3
4

a) Round and similar shaped sections
a

b) Rectangular and square sections
Key

1
2
3
4
a

tensile test piece
sample
rough specimen
test piece

For small products (d or w

≤ 2 5 mm) , the tes t p iece s hall, i f p o s s ib le, co ns is t o f an un- machined p art o f the b ar.

Figure 1 — Location of the test pieces in bars and rods

© ISO 2016 – All rights reserved

13


ISO 683-4:2016(E)

Annex A

(normative)
Ruling sections for mechanical properties

A

.

1



D

e


f
i

n

i

t
i

o

n

See 3.1.
A.2 Determination of the diameter of the equivalent ruling section
A.2.1

If the test pieces are taken from products with simple cross-sections and from positions with
A.2.1.1 to A.2.1.3

quas i two - dimens io nal heat flo w,

s hall ap p ly.

A.2.1.1 For rounds, the nominal diameter of the product (not comprising the machining allowance)
shall be taken as the diameter of the ruling section.
A.2.1.2 For hexagons and octagons, the nominal distance between two opposite sides of the crosssection shall be taken as the diameter of the ruling section.
A.2.1.3 For square and rectangular bars, the diameter of the ruling section shall be determined in
accordance with the example shown in Figure A.1.


14

© ISO 2016 – All rights reserved


ISO 683-4:2016(E)

Dimensions in millimetres

Y

1

Key

X width
Y thickness
1 diameter of the ruling cross-section
EXAMPLE For a rectangular bar with a section of 40 mm × 60 mm, the diameter of the ruling section is 50 mm.
Figure A.1 — Diameter of the equivalent ruling section for square and rectangular sections for
quenching in oil or water
A.2.2

Fo r o ther p ro duct

fo rms ,

the ruling s ectio n s hall b e agreed at the time o f enquiry and o rder.


NOTE For this purpose, the following procedure can serve as a guideline. The product is hardened in
accordance with usual practice. It is then cut so that the hardness and structure at the position of the ruling
s e c tion pro vide d

fo r

ta ki n g te s t pie ce s c a n b e de ter m i ne d . From a no ther p ro duc t o f the typ e u nder co n s ideration

a nd o f the s a me c a s t, a n end- quench pie ce i s ta ken

fro m

the pre s c rib e d p o s ition a nd te s te d i n the u s u a l way.

Then, the distance is determined at which the end-quench test piece shows the same hardness and structure as
the ruling section at the position provided for taking test pieces. On the basis of this distance, the diameter of the
ruling section is then estimated using Figures A.2 and A.3.

© ISO 2016 – All rights reserved

15


ISO 683-4:2016(E)

Dimensions in millimetres

Y
1


3

2

Key

X distance from the quenched end
Y bar diameter
1 surface
2 3/4 radius
3 centre
NOTE Source: Reference [10]
.

Figure A.2 — Relationship between the cooling rates in end-quench test pieces (Jominy test
pieces) and in quenched round bars in mildly agitated water

Dimensions in millimetres

Y
1

2

3

Key

X distance from the quenched end
Y bar diameter

1 surface
2 3/4 radius
3 centre
NOTE Source: Reference [10]
.

Figure A.3 — Relationship between the cooling rates in end-quench test pieces (Jominy test
pieces) and in quenched round bars in mildly agitated oil

16

© ISO 2016 – All rights reserved