1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationPD CEN ISO/TR 11811:2012Nanotechnologies Guidance on methods for nano- and microtribology measurementsPD CEN ISO/TR 11811:2012 PUBLISHED DOCUMENTNational forewordThis Published D
2、ocument is the UK implementation of CEN ISO/TR 11811:2012.The UK participation in its preparation was entrusted to T e c h n i c a l C o m m i t t e e N T I / 1 , N a n o t e c h n o l o g i e s .A list of organizations represented on this committee can be obtained on request to its secretary.This p
3、ublication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2012Published by BSI Standards Limited 2012ISBN 978 0 580 61397 5 ICS 07.030 Compliance with a British Standard cannot confer immuni
4、ty from legal obligations.This Published Document was published under the authority of the Standards Policy and Strategy Committee on 30 September 2012.Amendments issued since publicationDate T e x t a f f e c t e dTECHNICAL REPORT RAPPORT TECHNIQUE TECHNISCHER BERICHT CEN ISO/TR 11811 August 2012 I
5、CS 07.030 English Version Nanotechnologies - Guidance on methods for nano- and microtribology measurements (ISO/TR 11811:2012) Nanotechnologies - Directives relatives aux mthodes de mesure en nano- et microtribologie (ISO/TR 11811:2012) Nanotechnologien - Leitfaden fr nano- und mikrotribologische Me
6、ssverfahren (ISO/TR 11811:2012) This Technical Report was approved by CEN on 9 August 2010. It has been drawn up by the Technical Committee CEN/TC 352. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugo
7、slav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN
8、 DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. CEN ISO/TR 11811:2012: EPD CEN ISO/TR 11811:2012 CEN ISO/TR 11811:2012 (E) 3 Fo
9、reword This document (CEN ISO/TR 11811:2012) has been prepared by Technical Committee CEN/TC 352 “Nanotechnologies“, the secretariat of which is held by BSI, in collaboration with Technical Committee ISO/TC 229 “Nanotechnologies“. Attention is drawn to the possibility that some of the elements of th
10、is document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. PD CEN ISO/TR 11811:2012ISO/TR 11811:2012(E) ISO 2012 All rights reserved iiiContents PageForeword ivIntroduction v1 Scope 12 Terms and definitions . 13 Si
11、gnificance and use 14 Principle . 25 Apparatus and materials . 25.1 Test systems . 25.2 Test parameters . 46 Test procedure . 86.1 Different types of test . 86.2 Surface examination techniques . 117 Test reproducibility, repeatability and limits 128 Test report .12Bibliography .13PD CEN ISO/TR 11811
12、:2012ISO/TR 11811:2012(E)ForewordISO (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
13、 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 Commiss
14、ion (IEC) on all matters of electrotechnical standardization.International 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 co
15、mmittees 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.In exceptional circumstances, when a technical committee has collected data of a different kind from that which is normally publish
16、ed as an International Standard (“state of the art”, for example), it may decide by a simple majority vote of its participating members to publish a Technical Report. A Technical Report is entirely informative in nature and does not have to be reviewed until the data it provides are considered to be
17、 no longer valid or useful.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.ISO/TR 11811 was prepared by the European Committee for Standardization (CE
18、N) Technical Committee CEN/TC 352, Nanotechnologies, in collaboration with ISO Technical Committee ISO/TC 229, Nanotechnologies, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).iv ISO 2012 All rights reservedPD CEN ISO/TR 11811:2012ISO/TR 11811:2012(E
19、)IntroductionEvaluation of wear and friction in systems where interactions occur in the nanoscale is becoming increasingly important. There are two main areas of application. The first is in MEMS and NEMS devices, where tribological issues can determine the overall performance of the device. It is a
20、lso true that, in many cases, the tribological performance of macroscale contacts depends on the combination of what occurs at the micro- and nanoscale asperity contacts which actually take place when two surfaces come into contact.The development of nanotribology testing provides a way of generatin
21、g information and understanding these small-scale contacts. This understanding can then be used to model the performance of microscale devices and provide the basis for future models of sliding wear. ISO 2012 All rights reserved vPD CEN ISO/TR 11811:2012PD CEN ISO/TR 11811:2012Nanotechnologies Guida
22、nce on methods for nano- and microtribology measurementsIMPORTANT The electronic file of this document contains colours which are considered to be useful for the correct understanding of the document. Users should therefore consider printing this document using a colour printer.1 ScopeThis Technical
23、 Report establishes techniques for the evaluation of tribological performance of sliding contacts with a lateral size of between a few nanometres (nm) and 10 m, and where the applied load is between 50 N and 100 mN. It describes procedures for undertaking these measurements, and provides guidance on
24、 the effect of parameters on test results. It does not cover existing SPM techniques, such as frictional force microscopy and atomic force microscopy (AFM).2 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.2.1weardamage to a solid surface, generally
25、involving progressive loss of material, due to relative motion between that surface and a contacting substance or substancesASTM G402.2frictional forceresisting force tangential to the interface between two bodies where, under the action of an external force, one body moves or tends to move relative
26、 to the otherASTM G402.3coefficient of friction fdimensionless ratio of the frictional force, F, between two bodies to the normal force, N, pressing these bodies togetherASTM G40)NOTE 1 = F/N.NOTE 2 0.3 Significance and useThis Technical Report provides guidance on how to carry out micro- and nanotr
27、ibology tests, paying particular attention to the likely effect of test conditions and test parameters on the results to be obtained. This Technical Report does not specify a particular set of test conditions which should be used in a test. Appropriate test conditions should be chosen after consider
28、ing the eventual application for the materials being evaluated.TECHNICAL REPORT ISO/TR 11811:2012(E) ISO 2012 All rights reserved 1PD CEN ISO/TR 11811:2012ISO/TR 11811:2012(E)4 PrincipleTribology tests are conducted in test systems, which are designed to press one sample against another with a contr
29、olled relative force, while also imposing controlled relative motion. Conventionally, sliding/rolling tests are carried out with samples where the nominal contact areas have dimensions of several millimetres or more, and with test loads of the order of 1 N or greater. The focus of this Technical Rep
30、ort is on tribological tests where the contact areas have dimensions of between a few nanometres (nm) and 100 mN, and the loads are between 50 N and 100 mN.Both friction and wear can be measured using these tests. A major aim of the tests is to provide information on the tribological performance of
31、materials at the micro- and nanoscale. This information can be used to develop an understanding of the nanoscale mechanisms, which determine the wear and friction performance of the materials and the dependence of these mechanisms on the structure of the material.Application areas for these measurem
32、ents are micro- and nanoscale devices where there are sliding/rolling contacts, and the simulation of micro- and nanoscale contacts, which underlie all macroscale tribological contacts.5 Apparatus and materials5.1 Test systems5.1.1 Typical probe and sample geometriesTypically, a probe with a well-de
33、fined geometry is used to contact a flat sample (see 5.2.11). It is often important to simulate real contacts in these tests, where features such as the shape of the contact and geometrical parameters, such as the radius of curvature of the tip that is in contact in the real application are reproduc
34、ed. The assumed contact geometry, such as a pointed cone, cannot always be assumed to be correct at the contact scales experienced in the tests described in this Technical Report. The real contact geometry almost always has a rounded form at the very end of the contact probe. If a series of tests is
35、 to be carried out, it is also important to consider the repeatability of the probe geometry so that contact conditions can be repeated from one test to the next. Other details of the samples are given in this Technical Report.Although the words “probe” and “sample” are used in this subclause and in
36、 many places throughout this Technical Report, it should be emphasized that wear and damage to both probe and sample can take place.5.1.2 Holding samplesThe sample and probe need to be held firmly and in a well-defined way so that only intended motion of the samples can take place. Mechanical clampi
37、ng of samples is often preferable, but in some cases, an adhesive may be used to hold samples in place, e.g. where balls are used as the probe and need to be attached to a probe holder. If adhesives are used, it is important that the thickness of the adhesive be minimized to reduce the effect of any
38、 time-dependent flow in the adhesive and also to reduce the effect of the reduced stiffness introduced by the adhesive. Furthermore, if adhesives are used, sufficient time should be allowed for some adhesives to fully cure, develop maximum bond strength, as well as allow for dissipation of any exoth
39、ermal effects prior to the start of test.5.1.3 Motion generationThe relative motion generated between the probe and the sample can be achieved by either moving the sample or moving the probe. In either case, the motion that is generated should be well defined and reproducible so that repeated pass t
40、ests can be achieved. The small vertical displacements and applied loads which are applicable in tests mean that particular care is needed so that irregularities in the motion itself do not cause artefacts in the load that is applied.2 ISO 2012 All rights reservedPD CEN ISO/TR 11811:2012ISO/TR 11811
41、:2012(E)Additional care should be taken in order to minimize motion fluctuations and other effects due to ground motion, ambient thermal variations and air flow current (caused by ventilation systems, operator and laboratory equipment, to mention a few possible sources).Motion can be generated in se
42、veral ways. Piezoelectric actuators can be used, but these have limited range (normally about 100 m). Servo electric actuators, voice coils or stepper motors can also be used with gearing to give the requisite precision of motion. In all cases, it is important to have an independent measure of displ
43、acement.It is also important to design the sample stage and drive systems so that artefacts in either the z-motion and the x-y motion, such as hysteresis or backlash, are minimized.Three axes of motion are required to give the necessary x-y motion and also coarse z-motion to enable the probe to be b
44、rought close to the sample. The z-axis motion should be orthogonal to the motion in the x-y plane.Different types of motion can be used in tests. The most common is reciprocating motion in a back and forth manner in a single linear direction. A variant of this type of motion is where unidirectional
45、motion is required, such that movement takes place in a single direction with lift-off before return motion, followed by repeated contact to give multiple contact in the same direction. Circular motion is also quite common where the flat sample is simply spun by a motor drive.5.1.4 Application of no
46、rmal forceThe applied normal force can be generated by several different mechanisms.The simplest method is to use dead-weight loading. This is a passive technique, but care needs to be taken that load artefacts, such as parasitic friction, are not generated in the loading mechanism. Parasitic fricti
47、on is friction generated in the elements of the loading mechanism such that the actual applied force is different from the required force.Another common method for generating the applied normal force is to use the compression of a compliant element to generate a force, with the normal force determin
48、ed by measurement of the dimensional compression of the compliant element. The dimensional compression of the compliant element can be measured by displacement transducers such as fibre optic sensors, light deflection sensing or capacitance devices. It is important that the range and precision of th
49、e displacement transducers be matched to the deflection of the compliant element in the loading system so that the resolution and load range that are required can be achieved. Systems can be designed so that interchangeable compliant elements can be used to give different load resolutions and ranges.In both open and closed-loop control, the force magnitude is directly controlled, and the controlled data needs to be filtered appropriately for noise and spikes in values.Loading systems that use a compliant element to generate the applied load
