ASTM_F_1978_-_12.pdf

Designation:F197812Standard Test Method forMeasuring Abrasion Resistance of Metallic Thermal SprayCoatings by Using the Taber Abraser1This standard is issued under the fixed designation F1978;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.Scope*1.1 This test method quantifies the abrasion resistance ofmetallic coatings produced by thermal spray processes on flatmetallic surfaces.It is intended as a means of characterizingcoatings used on surgical implants.1.2 This test uses the Taber Abraser,2which generates acombination of rolling and rubbing to cause wear to the coatingsurface.Wear is quantified as cumulative mass loss.1.3 This test method is limited to flat,rigid specimens thatdo not react significantly with water and do not undergo aphase transformation or chemical reaction between roomtemperature and 100C in air.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 applicableregulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:3E691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodG195 Guide for Conducting Wear Tests Using a RotaryPlatform,Double-Head Abraser3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 abraser,ninstrument that is designed to determinethe resistance of surfaces to composite rolling and rubbingaction.3.1.2 particle shedding,nloss of surface particles andfragments from a coating.3.1.3 thermal spray coating,ncoating produced by spray-ing melted or softened powder or wire by means of combus-tible gases,plasma,or two-wire arc.3.1.4 weight loss,namount of mass removed by the testapparatus over the course of testing.4.Summary of Test Method4.1 This test method uses a Taber Abraser with H-22Calibrade(trademarked)wheels2and the 250-g mass of theabrading head without added weights.A specimen is abradedusing rotary rubbing action under controlled conditions ofpressure and abrasive action.The test specimen,mounted on aturntable platform,turns on a vertical axis against the slidingrotation of two abrading wheels.One abrading wheel rubs thespecimen outward toward the periphery and the other inwardtoward the center.The resulting abrasion marks form a patternof crossed arcs over an area of approximately 30 cm2.Specimens are abraded repeatedly and cleaned ultrasonicallyfor a set number(2 to 100)of rotational cycles.The specimensare weighed after each cleaning,and the mass loss is themeasure of abrasive wear to the specimen.5.Significance and Use5.1 This test method provides a means to evaluate theresistance to particle shedding of a thermal spray coating.Suchparticle shedding might occur during surgical insertion of animplant or as the result of micromotion of the implant afterinsertion.5.2 This abrasion test method may be useful for qualitycontrol analysis of a coating,and it can be used to evaluate theeffects of processing variables,such as substrate preparationbefore coating,surface texture,coating technique variables,orpostcoating treatments,any of which may influence the sus-ceptibility of the coating to particle shedding.1This test method is under the jurisdiction ofASTM Committee F04 on Medicaland Surgical Materials and Devices and is the direct responsibility of SubcommitteeF04.15 on Material Test Methods.Current edition approved June 1,2012.Published June 2012.Originallyapproved in 1999.Last previous edition approved in 2007 as F1978 00(2007)2.DOI:10.1520/F1978-12.2Trademarked.The sole source of supply of the apparatus known to thecommittee at this time is Taber Industries,North Tonawanda,NY 14120 USA.Ifyou are aware of alternative suppliers,please provide this information to ASTMHeadquarters.Your comments will receive careful consideration at a meeting of theresponsible technical committee,1which you may attend.3For 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.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.3 This abrasion test method is for flat plate-shaped speci-mens of a size sufficient that the wheels of the abrader do notleave the surface of the specimen.It is not recommended,however,for devices with other shapes or sizes.6.Apparatus6.1 Taber Abraser Model