ASTM_G_99_-_17.pdf

Designation:G9917Standard Test Method forWear Testing with a Pin-on-Disk Apparatus1This standard is issued under the fixed designation G99;the number immediately following the designation indicates the year of originaladoption or,in the case of revision,the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers a laboratory procedure fordetermining the wear of materials during sliding using apin-on-disk apparatus.Materials are tested in pairs undernominally non-abrasive conditions.The principal areas ofexperimental attention in using this type of apparatus tomeasure wear are described.The coefficient of friction mayalso be determined.1.2 This test method standard uses a specific set of testparameters(load,sliding speed,materials,etc.)that were thenused in an interlaboratory study(ILS),the results of which aregiven here(Tables 1 and 2).(This satisfies the ASTM form inthat“The directions for performing the test should include allof the essential details as to apparatus,test specimen,procedure,and calculations needed to achieve satisfactoryprecision and bias.”)Any user should report that they“fol-lowed the requirements of ASTM G99,”where that is true.1.3 Now it is often found in practice that users may followall instructions given here,but choose other test parameters,such as load,speed,materials,environment,etc.,and therebyobtain different test results.Such a use of this standard isencouraged as a means to improve wear testing methodology.However,it must be clearly stated in any report that,while thedirections and protocol in Test Method G99 were followed(iftrue),the choices of test parameters were different from TestMethod G99 values,and the test results were therefore alsodifferent from the Test Method G99 results.This use should bedescribed as having“followed the procedure of ASTM G99.”All test parameters that were used in such case must be stated.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.5 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2E178 Practice for Dealing With Outlying ObservationsG40 Terminology Relating to Wear and ErosionG117 Guide for Calculating and Reporting Measures ofPrecision Using Data from Interlaboratory Wear or Ero-sion Tests(Withdrawn 2016)32.2 DIN Standard:4DIN 50324 Testing of Friction and Wear3.Summary of Test Method3.1 For the pin-on-disk wear test,two specimens are re-quired.One,a pin with a radiused tip,is positioned perpen-dicular to the other,usually a flat circular disk.A ball,rigidlyheld,is often used as the pin specimen.The test machinecauses either the disk specimen or the pin specimen to revolveabout the disk center.In either case,the sliding path is a circleon the disk surface.The plane of the disk may be orientedeither horizontally or vertically.NOTE1Wear results may differ for different orientations.3.1.1 The pin specimen is pressed against the disk at aspecified load usually by means of an arm or lever and attachedweights.Other loading methods have been used,such ashydraulic or pneumatic.NOTE2Wear results may differ for different loading methods.3.2 Wear results are reported as volume loss in cubicmillimetres for the pin and the disk separately.When twodifferent materials are tested,it is recommended that eachmaterial be tested in both the pin and disk positions.3.3 The amount of wear is determined by measuring appro-priate linear dimensions of both specimens before and after the1This test method is under the jurisdiction of ASTM Committee G02 on Wearand Erosion and is the direct responsibility of Subcommittee G02.40 on Non-Abrasive Wear.Current edition approved Jan.1,2017.Published January 2017.Originallyapproved in 1990.Last previous edition approved in 2016 as G99 05(2016).DOI:10.1520/G0099-17.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Available from Beuth Verlag GmbH(DIN-DIN Deutsches Institut furNormung e.V.),Burggrafenstrasse 6,10787,Berlin,Germany,http:/www.en.din.de.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recomme