1、Designation: D7755 11 (Reapproved 2017)Standard Practice forDetermining the Wear Volume on Standard Test Pieces Usedby High-Frequency, Linear-Oscillation (SRV) Test Machine1This standard is issued under the fixed designation D7755; the number immediately following the designation indicates the year
2、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 practice covers a procedure for determining thewear
3、volume WVof wear scars and tracks on test piecestribologically stresses under high-frequency, linear-oscillationmotion using a SRV test machine by means of stylus tipprofilometry.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstanda
4、rd.1.3 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.1.4 This int
5、ernational standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT)
6、 Committee.2. Referenced Documents2.1 ASTM Standards:2D2714 Test Method for Calibration and Operation of theFalex Block-on-Ring Friction and Wear Testing MachineD2782 Test Method for Measurement of Extreme-PressureProperties of Lubricating Fluids (Timken Method)D3702 Test Method for Wear Rate and Co
7、efficient of Fric-tion of Materials in Self-Lubricated Rubbing ContactUsing a Thrust Washer Testing MachineD4175 Terminology Relating to Petroleum Products, LiquidFuels, and LubricantsD5620 Test Method for Evaluating Thin Film Fluid Lubri-cants in a Drain and Dry Mode Using a Pin and Vee BlockTest M
8、achine (Withdrawn 2010)3D5706 Test Method for Determining Extreme PressureProperties of Lubricating Greases Using a High-Frequency, Linear-Oscillation (SRV) Test MachineD5707 Test Method for Measuring Friction and Wear Prop-erties of Lubricating Grease Using a High-Frequency,Linear-Oscillation (SRV)
9、 Test MachineD6425 Test Method for Measuring Friction and Wear Prop-erties of Extreme Pressure (EP) Lubricating Oils UsingSRV Test Machine2.2 DIN Standards:4DIN 51631:1999-04 Special-boiling-point spirit Require-ments and testingDIN 51834-3:2008-12 Testing of lubricants Tribologicaltest in translato
10、ry oscillation apparatus Part 3: Determi-nation of tribological behaviour of materials in co-operation with lubricantsDIN EN ISO 13565-2:1998 Geometrical Product Specifica-tions (GPS) Surface texture: Profile method; Surfaceshaving stratified functional properties Part 2: Heightcharacterization usin
11、g linear material ratio curve (replacesof DIN 4776:1990: Measurement of surface roughness;parameters RK,RPK,RVK,Mr1,Mr2for the description ofthe material portion)3. Terminology3.1 Definitions:3.1.1 Hertzian contact area, nthe apparent area of contactbetween two non-conforming solid bodies pressed ag
12、ainst eachother.3.1.2 Hertzian contact pressure, nmagnitude of the pres-sure at any specified location in a Hertzian contact area, ascalculated from Hertzs equations of elastic deformation. TheHertzian contact pressure can also be calculated and reported1This practice is under the jurisdiction of AS
13、TM Committee D02 on PetroleumProducts, Liquid Fuels, and Lubricants and is the direct responsibility of Subcom-mittee D02.L0 on Industrial Lubricants and Engineering Sciences of High Perfor-mance Fluids and Solids.Current edition approved June 1, 2017. Published July 2017. Originally approvedin 2011
14、. Last previous edition approved in 2011 as D7755 11. DOI: 10.1520/D7755-11R17.2For 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 o
15、nthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Available from Deutsches Institut fur Normung e.V.(DIN), Beuth VerlagGmbH, Burggrafenstrae 6, D-10787 Berlin 30, Germany, http:/www.din.de.Copyright ASTM International, 100 Barr Harbor Drive, PO Bo
16、x 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 Recommendations issued by t
17、he World Trade Organization Technical Barriers to Trade (TBT) Committee.1as maximum value Pmaxin the centre of the contact or asPaverageas average over the total contact area. D41753.1.3 seizure, nlocalized fusion of metal between therubbing surfaces of the test pieces. D57063.1.3.1 DiscussionSeizur
18、e is usually indicated by a sharpincrease in coefficient of friction, wear, or unusual noise andvibration. In this test method, increase in coefficient of frictionis displayed on the chart recorder as permanent rise in thecoefficient of friction from a steady value.3.1.4 wear, ndamage to a solid sur
19、face, generally involv-ing progressive loss of material, due to the relative motionbetween that surface and a contacting substance or substances.D2714, D2782, D56203.1.5 wear rate, nthe rate of material removal or dimen-sional change due to wear per unit of exposure parameter; forexample, quantity o
20、f material removed (mass, volume, thick-ness) in unit distance of sliding or unit time.3.1.5.1 DiscussionAnother term sometimes used synony-mously is wear factor. D37023.2 Definitions of Terms Specific to This Standard:3.2.1 planimetric wear, Wq, nseen in the center of thewear track of the disk perp
21、endicular to the sliding direction attest end and can be understood as cross section area of wear.3.2.2 wear volume, Wv, nthe irreversible loss of volume tothe ball or the disk (flat) at end of test. D5707, D64253.3 Abbreviations:3.3.1 SRV, nSchwingung, Reibung, Verschlei, (German);oscillating, fric
22、tion, wear (English translation).4. Summary of Practice4.1 This practice applies to test pieces tribologicallystressed on a SRV test machine typically used in differentASTM (and DIN) test methods and are a test ball oscillatingagainst a flat test disk.4.2 As illustrated in Fig. 1, the same wear scar
23、 diameter onthe ball not consequently indicates materials loss, the amountof material loss and different volumetric material losses can berelated to exact one wear scar diameter.NOTE 1An extreme and ideal, but frequent case, is the case of alubricant, which fully protects against wear, but a wear sc
24、ar diameter ismarked only visibly by tribo-chemistry and the wear scar diametercorresponds to the initial Hertzian contact diameter describing the elasticdeformation. By using the ball diameter of diameter=10mm,theelastic constants for AISI 52100 (100Cr6H) and FN= 200 N, the initialHertzian contact
25、diameter calculates to 0.374 mm and for FN= 300 N is0.428 mm. When now unloading the ball after test, the elastic deformationis released and the initial shape recovers, showing, for example, no wear,but a marked wear scar, which is reported as wear scar diameter, even no,less or minor wear can be de
26、tected by means of stylus tip profilometry.4.3 The wear scar diameter on the test ball is measured andthe shape of the wear track on the disk is determined by meansof a stylus tip profilometer in the centre of the track length (seeFig. 2) and this perpendicular to the sliding direction.4.3.1 The wor
27、n or displaced volume (Wv,ball;Wv,flat) can becalculated by numerical methods5-7from the stylus tip profiledata and assuming an ideal shape of the test specimen.NOTE 2In general, the wear volume is calculated by integrating amultitude of cross section area taken at different lengths of the wear trac
28、k.The wear volume in this practice is based only on one cross section area(planimetric wear) in the centre of the wear track.4.4 The planimetric wear Wq,flatof the disk is derived froma 2D-profilogram by using a stylus tip profilometer.5. Significance and Use5.1 The determination of the wear volume
29、becomes intribological testing a key element, as it is more discriminativethan the wear scar diameter, because an optically visible wearscar diameter may or may not indicate wear on the surface ofthe ball and the wear track as an irreversible loss of material.Users of this test method should determi
30、ne whether resultscorrelate with field performance or other applications.NOTE 3It is believed, that tactile stylus tip profilometer determinesthe most realistic figure and are more frequent in use, than it can beachieved by optical profilometers operating in a non-contacting mode.6. Apparatus6.1 Mic
31、roscope, equipped with a filar eyepiece graduated in0.005 mm division or equipped with a micrometer stagereadable to 0.005 mm. Magnification should be sufficient to5Ruff,A. W., “Wear Measurement,” ASM Handbook, Vol 18, 1992, pp. 362369.6Klaffke, D., “Fretting Wear of Ceramics,” Tribology Internation
32、al, Vol 22, No.2, 1989, pp. 89101.7Kalin, M., and Viintin, J., “Use of Equations for Wear Volume Determinationin Fretting Experiments,” WEAR, 237, 2000, pp. 3948.NOTE 1R is smaller than R. The wear volumes are marked in blue.FIG. 1 BallComparison of Iso-wear Scar Diameters with WearVolume in Relatio
33、n to the Initial Radius R and the Radius in theScar Rat Test EndFIG. 2 Schematic Illustration of the Segmentation of the WearTrackD7755 11 (2017)2allow for ease of measurement. One to 10 times magnificationhas been found acceptable.6.2 Stylus Tip Profilometer:6.2.1 The stationary working place of th
34、e stylus tip profi-lometer should be composed of a stone (granite) base plate, thecolumn, a transverse unit, a skidless tracing arm (skidlesspick-up) and have the necessary software.6.2.2 The stylus tip has a tip radius of 2 m and a tip angleof 60 with a tip orientation (stylus position) of 90. Ther
35、esolution of the transverse unit is 0.1 m or better.7. Reagents and Materials7.1 Cleaning Solvent, the test balls and disks have to becleaned by a liquid solvent (non-chlorinated, non-film form-ing). (WarningFlammable. Health Hazard.)NOTE 4It is recommended to use special boiling point spirit type 2
36、according to DIN 51631:1999.8. Preparation of Apparatus8.1 MostASTM test methods related to SRV run with a ballsliding on a flat. In consequence and after the test, a wear scarmarks the ball and a wear track the flat (see Fig. 3).9. Procedure9.1 Cleaning of the SpecimenClean the test ball and diskby
37、 wiping the surfaces with laboratory tissue soaked with thecleaning solvent. Repeat wiping until no dark residue appearson the tissue. Immerse the specimen ball and disk in a beakerof the cleaning solvent under ultrasonic vibration for 10 min.Dry the test ball and disk with a clean tissue ensuring n
38、ostreaking occurs on the surface.9.2 Stylus Tip Profilometry:9.2.1 The wear scar and track should be free of seizuremarks.9.2.2 The measuring length should have on each side of thetrack at least 0.500 mm in order to define the base line of thesurface topography. A tracing speed of 0.15 mms has beenf
39、ound acceptable.9.2.3 Set manually the bars on the left side and right side ofthe track shown in the profilogram displayed on the screen inorder to define the borders. Set manually the horizontal bar forthe base of the surface topography (see Fig. X1.1). Thesoftware iterates (calculates) the planime
40、tric wear area.9.3 Calculation of the Wear VolumeThe variables used inEq 1-4 are illustrated in Figs. 2 and 4.9.3.1 The wear volume of the ball Wv,ballin mm3iscalculated by using Eq 1.Wv,ball5d12d2264S1R21RD(1)and by using:R5d2312 Wq, flat(2)where:R= resulting radius of the shape of the wear scar af
41、terthe test in mm;R = initial radius of the ball in mm;d1= the wear scar diameter on the ball parallel to thesliding direction in mm;d2= wear scar diameter on the ball perpendicular to thesliding direction in mm andWq, flat= planimetric wear of the wear track in the middle ofthe wear track length an
42、d seen perpendicular to thesliding direction in mm2.9.3.2 The shape of the wear track on the disk (flat) can becomposed from three sections in Fig. 2 and represent the basisfor Eq 3. Thus Eq 3 contains the element, B, plus the twoelements, A, describing the ball scar.9.3.2.1 The wear volume of the w
43、ear track on the flat diskWv,flatin mm3is calculated by using Eq 3.Wv,flat5d42d32 s!2641R1sWq,flat(3)where:d3= the total length of wear track in sliding direction inmm,d4= the width of the wear track in mm, ands = stroke in mm.andR5d4312Wq,flat(4)FIG. 3 Scheme of Wear Scar (Ball) and Track (Disk, Fl
44、at) on theTest SpecimenFIG. 4 Scheme of Variables Used to Calculated the Wear Volumeof Ball and DiskD7755 11 (2017)3where:measured diameter d4=d2in mm.NOTE 5The equations represent an approximation for strokes smallerthan 2 mm to 2.5 mm and assume thatRRandthewear height of thescar is R.NOTE 6The we
45、ar tracks produced by other oscillating test methodswith strokes of smaller than 2 mm may be also evaluated according to thispractice. The mathematical approach of this practice does not properlyreflect the aspects and shapes of longer wear tracks.10. Report10.1 Report the following information:10.1
46、.1 All parameters used to evaluate the lubricant asstated in the test method.10.2 Report both wear scar diameter measurements (d1andd2) taken on the ball.10.3 Report the planimetric wear area Wq,flatdetermined inthe wear track of the disk.10.4 Report the calculated wear volumes of ball Wv,ballanddis
47、k Wv,flat.11. Precision and Bias11.1 The calculation of the wear volumes is exact and noprecision limits can be assigned to this calculation.11.2 The accuracy of calculated wear volume will dependon the precision of the optical wear diameter measurement andof the planimetric surface area from the st
48、ylus tip profilometry.11.3 BiasThe calculation of the wear volume is exact andno bias can be assigned to this calculation.12. Keywords12.1 lubricating grease and oil; oscillation; SRV; wear; wearvolumeAPPENDIX(Nonmandatory Information)X1. MEASUREMENTS OF WEAR VOLUMEX1.1 Fig. X1.1 illustrates the set
49、ting of the bar limits bycursor on the screen in order to enable the software to iteratethe planimetric wear area. These vertical bars limits the leftborder and right border of the wear track width (see diameteror width d4) and horizontal bar indicates the average line of thesurface topography. The iterated surface area is marked inblack and the iteration result stated.FIG. X1.1 Profilogram Displayed On a Screen and Taken Perpendicular in the Center of the Wear Track on a SRV Test DiskD7755 11 (2017
