1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58ICS 83.060Rubber Determination of frictional propertiesBRITISH STANDARDBS ISO 15113:2005BS ISO 1511
2、3:2005This British Standard was published under the authority of the Standards Policy and Strategy Committee on 18 November 2005 BSI 18 November 2005ISBN 0 580 46833 XCross-referencesThe British Standards which implement international publications referred to in this document may be found in the BSI
3、 Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for it
4、s correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations.Summary of pagesThis document comprises a front cover, an inside front cover, the ISO title page, pages ii to v, a blank page, pages 1 to 20, an inside back cover and a back cover.The
5、BSI copyright notice displayed in this document indicates when the document was last issued.Amendments issued since publicationAmd. No. Date CommentsA list of organizations represented on this committee can be obtained on request to its secretary. present to the responsible international/European co
6、mmittee any enquiries on the interpretation, or proposals for change, and keep UK interests informed; monitor related international and European developments and promulgate them in the UK.National forewordThis British Standard reproduces verbatim ISO 15113:2005 and implements it as the UK national s
7、tandard. It supersedes BS ISO 15113:1999 which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee PRI/22, Physical testing of rubber, which has the responsibility to: aid enquirers to understand the text;Reference numberISO 15113:2005(E)INTERNATIONAL STANDARD I
8、SO15113Second edition2005-10-15Rubber Determination of frictional properties Caoutchouc Dtermination des proprits frictionnelles BS ISO 15113:2005ii iiiContents Page Foreword iv Introduction v 1 Scope . 1 2 Normative references . 1 3 Terms and definitions. 1 4 Principle. 2 5 Apparatus 3 6 Test surfa
9、ces. 3 7 Preparation 4 8 Conditioning 6 9 Test parameters 6 10 Cleaning or renewal of the test track 7 11 Procedure A (initial friction measurements) 7 12 Procedure B (service behaviour) 8 13 Procedure C (tests with added lubricants or contaminants) . 8 14 Stick-slip 9 15 Presentation of results. 9
10、16 Test report . 12 Annex A (informative) Design principles . 13 Annex B (informative) Ball-on-flat geometry . 15 Annex C (informative) Static friction and “stiction” . 16 Annex D (informative) Other parameters . 17 Bibliography . 20 BS ISO 15113:2005iv Foreword ISO (the International Organization f
11、or 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 th
12、e 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. Internat
13、ional Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication
14、 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 document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
15、 ISO 15113 was prepared by Technical Committee ISO/TC 45, Rubber and rubber products, Subcommittee SC 2, Testing and analysis. This second edition cancels and replaces the first edition (ISO 15113:1999), of which it constitutes a minor revision, the main purpose of which was to update the normative
16、references clause. It also incorporates Technical Corrigendum ISO 15113:1999/Cor. 1:2001. BS ISO 15113:2005vIntroduction Various geometrical arrangements can be used when measuring friction, but each is likely to give a different value for , the coefficient of friction. Each may be appropriate in pa
17、rticular circumstances, but it is desirable that some standard method utilizing specified test conditions be employed when comparisons between materials are undertaken. Rubber samples are most readily available in sheet form, and for many practical applications measurement between two planar surface
18、s most nearly approaches service behaviour. Consequently, this is the most widely used geometry. For this geometry, the apparatus used needs careful design in order to ensure reproducible contact between the surfaces, and this is discussed in Annex A. Where rubber moulding facilities are available,
19、some workers prefer to use a hemispherical rubber slider and a planar test track. This gives a more definable contact area and minimizes the errors involved if the friction plane does not contain both the line of action of the load cell and that of the towing force. However, when this geometry is us
20、ed, the frictional force is not proportional to the normal load (see Annex B), and the contact area is estimated from a knowledge of the modulus of the rubber. Hence care should be taken when quoting values for coefficients of friction. The big disadvantage of the method is that special test pieces
21、need to be moulded from unvulcanized rubber, and rubber products cannot be accommodated. Finally, since some degree of wear is inseparable from friction, extended testing will produce a “flat” on the hemispherical test piece. Frequent inspection of the test surface is recommended, therefore, to ensu
22、re that the initial contact geometry is maintained. The alternative “ball-on-flat” geometry where a hard ball slides on a flat rubber surface is not an exact equivalent. The ploughing action of the ball through the rubber results in an energy loss by hysteresis which gives a higher measured coeffici
23、ent of friction. However, in some circumstances this may be an appropriate test procedure. Although there may be some uncertainty in the contact area using plane-on-plane geometry, this International Standard is based on this geometry because of its wide practical applicability. However, it is empha
24、sized that it is necessary to have a well designed apparatus with the line of action of the load cell included in the plane of contact of the test pieces (see Annex A). The method can be adapted to cover other contact geometries to suit particular products, including the ball-on-flat geometry set ou
25、t in Annex B. This International Standard is based on linear motion, and guidance on the experimental arrangement is given in Annex A. Because friction generates heat, it is usual to restrict testing to velocities typically below 1 000 mm/min in order to avoid a large temperature rise at the interfa
26、ce. If service conditions involve high speeds, then an entirely different method based on rotary motion is more appropriate as discussed in Annex A. The method of test set out here enables kinetic friction to be measured at a number of fixed velocities. It can be arranged that the lowest velocity is
27、 such that movement is barely discernible, and this gives an approximation to frictional behaviour close to zero velocity (static friction). This may be different from the starting friction, which may involve some element of adhesion (stiction) as discussed in Annex C. This method is suitable for me
28、asuring the initial friction only if the machine has a constant-rate-of-load facility and a sufficiently compliant load cell. A discussion on static friction and the correct approach to its measurement is given in Annex C. Rubber friction is complex, and the coefficient of friction is dependent on t
29、he contact geometry, normal load, velocity and temperature, as well as the composition of the rubber. A discussion of the influence of these parameters and some other factors which affect measurement is presented in Annex D. BS ISO 15113:2005blank1Rubber Determination of frictional properties 1 Scop
30、e This International Standard outlines the principles governing the measurement of coefficient of friction and describes a method suitable for measuring the coefficient of friction of a rubber against standard comparators, against itself, or against any other specified surface. 2 Normative reference
31、s The following referenced documents are indispensable for the application 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 5893:2002, Rubber and plastics test equipme
32、nt Tensile, flexural and compression types (constant rate of traverse) Specification 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. 3.1 coe
33、fficient of friction ratio of the frictional force opposing motion between two surfaces to the normal force between the surfaces under specified test conditions NOTE Coefficient of friction is dimensionless and its value is not restricted to numbers less than unity. 3.2 area of contact whole of the
34、apparent area made between the two test surfaces (test track and test piece) NOTE The real area of contact (see 3.3) may well be less than this. 3.3 real area of contact sum total of the minute contact areas at which the two test surfaces touch 3.4 velocity of test velocity with which one surface is
35、 driven relative to the other NOTE If stick-slip (see 3.5) occurs, this will then be the mean velocity with which one surface moves relative to the other. BS ISO 15113:20052 3.5 stick-slip condition in which the actual velocity between the surfaces oscillates between two extremes about the test velo
36、city, resulting in corresponding oscillations in the measured frictional force 3.6 test track surface against which the rubber is to be tested NOTE The test track may be made of the same material as the rubber under test or it may be different. 3.7 temperature of test temperature of the test apparat
37、us and its environment NOTE Since friction generates heat, this may differ from the actual temperature of one or both of the test surfaces. 3.8 lubricant substance introduced between two surfaces to lower the coefficient of friction NOTE A lubricant is usually a liquid, but in some circumstances sol
38、id powders are used, e.g. talc. Usually, lubricants are introduced deliberately. 3.9 contaminant any substance present on either test surface not of the same composition as that surface NOTE A contaminant may act as a lubricant. Usually, in service, contaminants are introduced inadvertently. 3.10 st
39、iction force needed to move one surface over another when the external normal load is reduced to zero NOTE This is an apparent frictional force, but no coefficient of friction can be calculated since the normal force is zero. See Annex C. 3.11 static friction frictional force needed to start motion
40、(i.e. the frictional force at zero velocity) NOTE Where there is an external normal load, a coefficient of static friction can be calculated. Static friction often involves some element of stiction. See Annex C. 4 Principle Two test surfaces are brought together under the action of a measured normal
41、 load. A mechanism slides one of the surfaces over the other at a measured velocity, and the force opposing motion is monitored and recorded. The ratio of this frictional force to the normal load at any instant is the coefficient of friction at that time. Since the test itself will alter the surface
42、s and may change the temperature at the interface, the measured coefficient of friction may change as the test proceeds. In an ideal apparatus, the line of action of the force-measuring equipment will lie in the plane of the two contacting surfaces. This may be either a horizontal or a vertical plan
43、e. BS ISO 15113:200535 Apparatus 5.1 Device, with provision for attaching two friction surfaces and capable of providing linear motion between the surfaces for a distance of typically 100 mm at a number of fixed velocities, typically between 0,5 mm/min and 1 000 mm/min. This may be a dedicated devic
44、e or, alternatively, a tensile-testing machine may be adapted for the purpose. 5.2 Means of providing several measured normal loads between the surfaces within the range 1 N to 200 N. When the test track is horizontal, suitable weights may be used directly to provide the normal load, but on a machin
45、e with a vertical test track it will be necessary to use a bell crank lever system to convert the vertical gravitational force into a horizontal normal force. 5.3 Series of load cells or, alternatively, a load cell with multiple ranging, conforming to at least class 1 as defined in ISO 5893:2002, fi
46、tted with a means of recording the output and fastened to one of the friction surfaces, with ranging or other means of indicating the frictional force to an accuracy of 1% throughout the range of measurement. NOTE Corresponding to the range of normal loads stated in 5.2, the measured frictional forc
47、es are likely to be within the range 0,1 N to 1 kN. 5.4 Environmental cabinet (if the effects of temperature are to be studied), to contain the apparatus and the two surfaces under test (but not the load cell), with a means of measuring and recording the temperature to an accuracy of 0,5 C. The envi
48、ronmental chamber shall not make physical contact with any moving parts. NOTE 1 The exclusion of a condensation-forming atmosphere from the test environment is extremely difficult, and the formation of ice crystals or particles or films on the test surfaces can only be assessed visually. NOTE 2 To a
49、void the formation of ice when testing at temperatures at or below 0 C, a very dry atmosphere (e.g. 5 % to 10 % r.h.) is needed. 5.5 Means of avoiding stick-slip, as the whole apparatus (including the load cell) needs to be as stiff as possible. All connections shall be made with rods and not with wire. Where an apparatus is designed to be attached to a tensile-testing machine, then a machine with a high degree of stiffness shall be chosen. In practice, this means a tensile-testing machine with a load capacity some 20 times gr
