ISO 4649:2017

INTERNATIONAL ISO
STANDARD 4649
Fourth edition
2017-09
Rubber, vulcanized or
thermoplastic — Determination of
abrasion resistance using a rotating
cylindrical drum device
Caoutchouc vulcanisé ou thermoplastique — Détermination de la
résistance à l'abrasion à l'aide d'un dispositif à tambour tournant
Reference number
ISO 4649:2017(E)
©
ISO 2017

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ISO 4649:2017(E)

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ISO 4649:2017(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Apparatus and materials. 4
6 Calibration . 5
7 Test pieces . 5
7.1 Type and preparation . 5
7.2 Number . 6
7.3 Time interval between vulcanization or forming and testing . 6
7.4 Conditioning . 6
8 Test temperature . 6
9 Procedure. 6
9.1 General test procedure . 6
9.2 Comparison against standard reference compounds or user-defined
reference compounds . 7
9.3 Density . 8
10 Expression of results . 8
10.1 General . 8
10.2 Relative volume loss, ΔV . 8
rel
10.3 Abrasion resistance index . 9
11 Precision . 9
12 Test report . 9
Annex A (normative) Suitable abrasive sheet .10
Annex B (normative) Standard and user-defined reference compounds .11
Annex C (normative) Calibration schedule .16
Annex D (informative) Precision and bias .19
Bibliography .21
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ISO 4649:2017(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following
URL: www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 45, Rubber and rubber products,
Subcommitee SC 2, Testing and analysis.
This fourth edition cancels and replaces the third edition (ISO 4649:2010), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— the normative references have been updated;
— details regarding relative volume loss (3.2) have been added;
— the text has been updated for a better understanding.
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ISO 4649:2017(E)

Introduction
Various types of laboratory test equipment for wear resistance of rubber compound have been developed
depending on the products to which rubber compounds have been applied in the past. Methods and
equipment are briefly introduced in ISO 23794 and the test method using a rotating cylindrical drum
device is described in detail in this document.
Because factors such as the grade of abrasive sheet, the type of adhesive used in the manufacture of the
sheet and contamination and wear caused by previous testing lead to variations in the absolute values
of abrasion loss, all tests are comparative. Runs with a reference compound are included so that the
results can be expressed either as a relative volume loss compared to a calibrated abrasive sheet or as
an abrasion resistance index compared to a reference compound.
This document describes two methods and specifies two standard reference compounds that can
be chosen freely, although some combinations are more frequently used in practice. Considerable
experience has been accumulated using the relative volume loss calculation in 10.2 for method A with
reference compound no. 1 and method B with reference compounds no. 1 and no. 2.
When using standard reference compound no. 1 with a non-rotating test piece, a very important part of
the method is the preparation of the abrasive sheet and its calibration.
Relative volume loss can be calculated for either test method with another reference compound, if the
defined mass loss is known.
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INTERNATIONAL STANDARD ISO 4649:2017(E)
Rubber, vulcanized or thermoplastic — Determination of
abrasion resistance using a rotating cylindrical drum device
WARNING 1 — Persons using this document should be familiar with normal laboratory practice.
This document does not purport to address all of the safety problems, if any, associated with its
use. It is the responsibility of the user to establish appropriate safety and health practices and to
determine the applicability of any other restrictions.
WARNING 2 — Certain procedures specified in this document might involve the use or generation
of substances or the generation of waste, that could constitute a local environmental hazard.
Reference should be made to appropriate documentation on safe handling and disposal after use.
1 Scope
This document specifies two methods for the determination of the resistance of rubber to abrasion by
means of a rotating cylindrical drum device.
The methods involve determination of the volume loss due to the abrasive action of rubbing a test piece
over a specified grade of abrasive sheet. Method A is for a non-rotating test piece and method B is for a
rotating test piece. For each method, the result can be reported as a relative volume loss or an abrasion
resistance index.
These test methods are suitable for comparative testing, quality control, specification compliance
testing, referee purposes and research and development work. No close relation between the results of
this abrasion test and service performance can be inferred.
NOTE The abrasion loss is often more uniform using the rotating test piece because the whole surface of
the test piece is in contact with the abrasive sheet over the duration of the test. However, there is considerable
experience using the non-rotating test piece.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 2230, Rubber products — Guidelines for storage
ISO 2393, Rubber test mixes — Preparation, mixing and vulcanization — Equipment and procedures
ISO 2781, Rubber, vulcanized or thermoplastic — Determination of density
ISO 7619-1, Rubber, vulcanized or thermoplastic — Determination of indentation hardness —
Part 1: Durometer method (Shore hardness)
ISO 9298:2017, Rubber compounding ingredients — Zinc oxide — Test methods
ISO 18899:2013, Rubber — Guide to the calibration of test equipment
ISO 23529, Rubber — General procedures for preparing and conditioning test pieces for physical test methods
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
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ISO 4649:2017(E)

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
abrasion resistance
resistance to wear by mechanical action upon a surface
Note 1 to entry: For the purposes of this document, the abrasion resistance is expressed either as a relative
volume loss (3.2) compared to an abrasive sheet calibrated using a standard reference compound or as an abrasion
resistance index (3.3) compared to a reference compound.
3.2
relative volume loss
ΔV
rel
volume loss of the test rubber after being subjected to abrasion by an abrasive sheet which will cause a
reference compound to lose a defined mass under the same specified conditions of test
Note 1 to entry: Relative volume loss is expressed in cubic millimetres.
3.3
abrasion resistance index
ARI
I
AR
ratio of the volume loss of a reference compound to the volume loss of the test rubber, measured under
the same specified conditions of test
Note 1 to entry: A smaller number indicates a lower abrasion resistance (3.1).
Note 2 to entry: The abrasion resistance index is expressed as a percentage.
4 Principle
A cylindrical rubber test piece is made to slide over an abrasive sheet of specified abrasive grade under
a specified pressure over a given distance. The test piece may be rotating or non-rotating during the
test. The abrasive sheet is attached to a rotating cylindrical rotating drum against which the test piece
is held and across which it traverses.
The loss of mass of the test piece is determined and used together with the density of the test piece
material to calculate the volume loss. The volume loss of the test piece is compared to that of a reference
compound tested under the same conditions.
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ISO 4649:2017(E)

Dimensions in millimetres
Overhead view
Key
1 sledge 6 abrasive sheet
2 swivel arm 7 double-sided adhesive tape
3 test piece holder F vertical force
a
4 test piece Rotational speed 40 r/min ± 1 r/min.
b
5 cylinder, diameter 150 mm ± 0,2 mm, length 500 mm Gap of size ≤ 2 mm.
Figure 1 — Schematic illustration of apparatus
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ISO 4649:2017(E)

5 Apparatus and materials
5.1 Abrasion machine.
The test apparatus (see Figure 1) consists of a laterally movable test piece holder and a rotatable
cylinder to which the abrasive sheet (5.2) is fixed.
The cylinder shall have a diameter of 150 mm ± 0,2 mm and a length of about 500 mm and shall be
rotated at a speed of 40 r/min ± 1 r/min, the direction of rotation being as indicated in Figure 1.
The test piece holder shall have a cylindrical opening, the diameter of which can be adjusted from
15,5 mm to 16,3 mm and a device for adjusting the length of the test piece protruding from the opening
to 2 mm ± 0,2 mm. The holder shall be mounted on a swivel arm that, in turn, is attached to a sledge that
can be moved laterally on a spindle. The lateral displacement of the holder shall be 4,20 mm ± 0,04 mm
per revolution of the drum (see Note 1). Suitable attachments may be provided to rotate the test piece
during the test run by rotation of the test piece holder (method B), preferably at the rate of 1 revolution
per 50 revolutions of the drum.
NOTE 1 With this lateral movement, the test piece passes over any one area of the abrasive sheet four times.
The swivel arm and test piece holder shall be free from vibration during operation and so disposed
that the test piece is pressed against the drum with a vertical force of 10 N ± 0,2 N. For investigation of
extremely soft or hard materials, the force may be changed to 5 N ± 0,1 N or 20 N ± 0,4 N, respectively
(see Note 2). The force is generated by adding masses to the top of the test piece holder.
NOTE 2 A force of 5 N is typically used for rubbers softer than approximately 40 IRHD and a force of 20 N is
used for hard rubbers of 80 IRHD and above.
The abrasive sheet shall be attached to the drum using three evenly spaced strips of double-sided
adhesive tape extending along the complete length of the drum. The width of the margins that are not
touched by the test piece shall be equal. Care shall be taken to ensure that the abrasive sheet is firmly
held so as to present a uniform abrasive surface over the whole area of the cylinder. One of the strips
shall be placed where the ends of the abrasive sheet meet. Ideally, the ends should meet exactly, but any
gap left between them shall not exceed 2 mm. The adhesive tape shall be about 50 mm wide and not
more than 0,2 mm thick.
The abrasion run starts by bringing the test piece into contact with the abrasion sheet.
Placement of the test piece on the sheet at the beginning of a test run and its removal after an abrasion
run of 40 m ± 0,2 m (equivalent to 84 revolutions) shall be automatic. In special cases of very high volume
loss of the test piece, the abrasion distance may be reduced to 20 m ± 0,1 m (equivalent to 42 revolutions).
In that case, a revolution counter or automatic stopping device should preferably be used.
NOTE 3 For rubbers with very high mass loss, a distance of 10 m has been used.
To protect the abrasive sheet from damage by the test piece holder, a device for switching off the
apparatus just before the lower edge of the test piece holder touches the sheet is recommended.
The test machine may be equipped with a vacuum hose and a brush to aid in the removal of debris from
the machine.
5.2 Abrasive sheet.
An abrasive sheet made with aluminium oxide of grain size 60, at least 400 mm wide, 474 mm ± 1 mm
long and 1 mm average thickness, shall be used as the abrasive medium.
In a test using a non-rotating test piece (method A) of standard reference compound no. 1 (see Table B.1),
this abrasive sheet shall cause a mass loss of between 180 mg and 220 mg for an abrasion distance of 40 m.
When each new sheet is first used, the direction of motion shall be indicated on the sheet, as it is
important that the same direction be used for all subsequent test runs.
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ISO 4649:2017(E)

The characteristics of a suitable abrasive sheet are specified in Annex A.
5.3 Hollow drill.
The drill shown in Figure 2 is an example of a tool suitable for the preparation of test pieces that are not
moulded (see 7.1). The speed of rotation of the drill needs to be at least 1 000 r/min for most rubbers,
and even higher for rubbers with a hardness of less than 50 IRHD. A sufficient cooling of the tool is
necessary to prevent an undesired heating of the drill.
Dimensions in millimetres
Figure 2 — Example of a hollow drill for test piece preparation
5.4 Balance.
The balance shall be of sufficient accuracy to enable the mass loss of a test piece to be determined
to ±1 mg.
5.5 Standard reference compounds.
Specifications for standard reference compounds are given in detail in Annex B.
6 Calibration
The test apparatus shall be calibrated in accordance with the schedule given in Annex C.
7 Test pieces
7.1 Type and preparation
The test pieces shall be cylindrical in shape, of diameter 16 mm ± 0,2 mm, with a minimum height of 6 mm.
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ISO 4649:2017(E)

Test pieces are normally prepared from moulded sheets using the hollow drill (5.3) or other rotating
cutting tools. During cutting, the cutting edge shall be lubricated with water to which a wetting agent
has been added. Punching of the test pieces is not permitted.
NOTE 1 If the cut sample is not satisfactory, cylinder vibration occurs.
Alternatively, test pieces may be vulcanized or formed in a mould.
NOTE 2 It is sufficient to rub off only one side of the test piece.
If test pieces of the required thickness are not available, the necessary thickness may be obtained by
bonding a piece of the test rubber to a base element of hardness not less than 80 IRHD. The thickness of
the test rubber shall be not less than 2 mm.
7.2 Number
A minimum of three test runs shall be carried out for each rubber being tested. A new test piece shall be
used for each test run. For referee purposes, use 10 test pieces.
In the case of the standard reference compounds no. 1 (see Table B.1) and no. 2 (see Table B.4), three
test runs may be carried out on one test piece in order to reduce wastage.
7.3 Time interval between vulcanization or forming and testing
Unless otherwise specified, the time interval between the date the material was formed and testing
shall be in accordance with ISO 23529.
7.4 Conditioning
Condition all test pieces at standard laboratory temperature, in accordance with ISO 23529, for a
minimum period of 16 h immediately before testing.
For rubbers which are sensitive to moisture, the humidity should also be controlled.
8 Test temperature
The test shall be carried out at standard laboratory temperature (see ISO 23529).
During a test run, there can be a considerable increase in temperature at the abrading interface, which
can lead to temperature rises within the test piece. For the purposes of this document, such temperature
rises are to be disregarded, the temperature of test being that of the ambient atmosphere and of the test
piece before commencing the test.
9 Procedure
9.1 General test procedure
Before each test, any rubber debris left on the abrasive sheet from a previous abrasion test shall be
removed with a brush. A brush of about 55 mm diameter with hard nylon or similar bristles and
about 70 mm in length is recommended for this purpose. In some cases, a blank test with a reference
compound (see Note 1) will effectively clean the abrasive sheet (see Note 2).
Brushes with metal bristles are not recommended as they shorten the life of the abrasive sheet.
NOTE 1 The reference compound used only for cleaning purposes does not necessarily have to meet the
stringent requirements of the reference compound used for test purposes.
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ISO 4649:2017(E)

NOTE 2 Some laboratories have found that blowing removes the debris left by some test rubbers better than
brushing. Safety blow guns which give a maximum pressure of 0,2 MPa at the nozzle when the nozzle is blocked
off, used with a supply air pressure between 0,5 MPa and 0,9 MPa, have given good results.
For method A, the non-rotating test piece shall be used. For method B, the rotating test piece shall
be used. Standard reference compound no. 1 (see Table B.1) or no. 2 (see Table B.4) or a user-defined
reference compound shall be used as the reference compound. The method and the reference compound
used shall be stated in the test report because the results obtained can differ. For measurements
intended to be comparable, the same conditions shall be used for all test rubbers and the reference
compound.
Weigh the test piece to the nearest 1 mg. Fix the test piece in the test piece holder in such a way that a
length of 2,0 mm ± 0,2 mm protrudes from the opening. This length shall be checked by means of a gauge.
The test piece shall normally be pressed against the drum with a vertical force of 10 N ± 0,2 N. If, for
special cases, the vertical force is reduced to 5 N ± 0,1 N or increased to 20 N ± 0,4 N, this shall be stated
in the test report.
Turn on the suction, if it is provided. Move the test piece holder and sledge to the starting point and
start the automatically controlled test run. Check for vibration in the test piece holder. This test method
does not yield meaningful results if there is abnormal vibration in the test piece holder. The test run is
stopped automatically after an abrasion distance of 40 m. When relatively large mass losses (usually
more than 400 mg in 40 m) occur, the test run may be stopped after 20 m and the length of exposed
test piece reset to 2,0 mm ± 0,2 mm so that the remaining 20 m of the run can be completed. At no time
shall the height of the test piece be less than 5 mm. If the mass loss is greater than 600 mg in 40 m, the
abrasion distance shall be reduced to 20 m and this shall be stated in the test report. The results shall
be multiplied by 2 so that the mass loss can still be given for an abrasion distance of 40 m.
For non-rotating test pieces that are removed during the test, care shall be taken to ensure that the test
piece is always replaced in the test piece holder in the same way.
For bonded test pieces, care shall be taken that the test pieces are not abraded down to the bond line or
if a sample with a fabric reinforcement is used in fabric line (if necessary, use a 20 m run).
Weigh the test piece to the nearest 1 mg after the test run. Sometimes a small edge hanging from the
test piece has to be pulled off before weighing, especially if a non-rotating test piece is used.
Carry out all test runs on the same rubber consecutively.
9.2 Comparison against standard reference compounds or user-defined reference
compounds
The test rubbers are compared against one of the two standard reference compounds specified in
Annex B or a user-defined reference compound.
The mass loss of the reference compound shall be determined by carrying out a minimum of three test
runs both before and after each test series with the test rubber following the procedure in 9.1. There
shall be a maximum of 10 runs of test rubber test pieces in each test series. Do not split the runs on a
test rubber between series. When repeat runs are made on the same test piece of one of the standard
reference compounds, allow sufficient time between such runs for the temperature of the whole of the
test piece to return to standard laboratory temperature.
For rubbers which have a tendency to smear, determine the mass loss of the reference compound after
each run with the test rubber. In extreme cases of smearing, there is a considerable reduction in mass
loss of the reference compound measured after the test run compared to that measured before the test
run. This is due to the fact that the abrasive sheet is being “cleaned” by the reference compound, as
opposed to the reference compound being abraded by the sheet. If the reduction in mass loss of the
reference compound is greater than 10 %, then the method is not valid.
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ISO 4649:2017(E)

Variations in the test method have been proposed to overcome this problem, including the use of
a 40 grit abrasive sheet. Any such variations used shall be agreed upon by all parties involved and
carefully noted in the test report [see Clause 12, c) 3)].
9.3 Density
Determine the density of the test material by one of the methods specified in ISO 2781.
10 Expression of results
10.1 General
The results may be expressed either as a relative volume loss or as an abrasion resistance index.
Calculate the mean value of the mass losses of the test rubber, Δm , and of the reference compound, Δm ,
t r
from the separate determinations.
A value for Δm of 200 mg has been established as the mid-point of the calibration range (see B.2.4.3)
const
for the abrasive sheet (see Annex A) using method A with standard reference compound no. 1 and a
value of 250 mg using method B with standard ref
...