ASTM_G_176_-_03_2009.pdf

Designation:G17603(Reapproved 2009)Standard Test Method forRanking Resistance of Plastics to Sliding Wear UsingBlock-on-Ring Wear TestCumulative Wear Method1This standard is issued under the fixed designation G176;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers laboratory procedures for de-termining the resistance of plastics to sliding wear.The testutilizes a block-on-ring friction and wear testing machine torank plastics according to their sliding wear characteristicsagainst metals or other solids.1.2 An important attribute of this test is that it is veryflexible.Any material that can be fabricated into,or applied to,blocks and rings can be tested.Thus,the potential materialscombinations are endless.In addition,the test can be run withdifferent gaseous atmospheres and elevated temperatures,asdesired,to simulate service conditions.1.3 Wear test results are reported as the volume loss in cubicmillimetres for the block and ring.Materials of higher wearresistance will have lower volume loss.1.4 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.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:2D618 Practice for Conditioning Plastics for TestingD2714 Test Method for Calibration and Operation of theFalex Block-on-Ring Friction and Wear Testing MachineE122 Practice for Calculating Sample Size to Estimate,WithSpecified Precision,the Average for a Characteristic of aLot or ProcessE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodG40 Terminology Relating to Wear and ErosionG77 Test Method for Ranking Resistance of Materials toSliding Wear Using Block-on-Ring Wear Test3.Terminology3.1 Definitions:3.1.1 weardamage to a solid surface,generally involvingprogressive loss of material,due to relative motion betweenthat surface and a contacting substance or substances.G404.Summary of Test Method4.1 A test plastic block is loaded against a metal test ringthat rotates at a given speed for a given number of revolutions.Block scar volume is calculated from the block scar width.Thefriction force required to keep the block in place may becontinuously measured during the test with a load cell.Whenthis is done,the friction force data are combined with normalforce data to obtain values for the coefficient of friction andreported.5.Significance and Use5.1 The significance of this test method in any overallmeasurement program directed toward a service applicationwill depend on the relative match of test conditions to theconditions of the service application.5.2 This test method prescribes the test procedure andmethod of calculating and reporting data for determining thesliding wear resistance of plastics,using cumulative volumeloss.5.3 The intended use of this test is for coarse screening ofplastics in terms of their resistance to sliding wear.6.Apparatus and Test Specimens6.1 Test SchematicA schematic of the block-on-ring weartest geometry is shown in Fig.1.In the figure,the friction loadcell is enlarged.6.2 Test RingAtypical test ring is shown in Fig.2.The testring must have an outer diameter of 34.99 6 0.025 mm(1.3771This 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 May 1,2009.Published May 2009.Originallyapproved in 2003.Last previous edition approved in 2003 as G17603.DOI:10.1520/G0176-03R09.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6 0.001 in.)with an eccentricity between the inner and outersurfaces of no greater than 0.00125 mm(0.0005 in.).Forcouples where surface condition is not under study,it isrecommended that the outer diameter be a ground surface witha roughness of 0.152 to 0.305 m(6 to 12 in.)rms or centerline average(CLA),in the direction of motion.However,alternate surface conditions may be evaluated in the test,asdesired.It should be kept in mind that surface condition canhave an effect on sliding wear results.NOTE1A commonly used test ring is a carburized 462