1、Designation: D7755 11Standard 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 oforiginal adoptio
2、n 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 volume WVof wear s
3、cars 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 as thestandard. The values given in parentheses are for informationonly.1.3 This stand
4、ard 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 AS
5、TM 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 Coefficient ofFriction of Materials in Sel
6、f-Lubricated Rubbing ContactUsing a Thrust Washer Testing MachineD4175 Terminology Relating to Petroleum, PetroleumProducts, and LubricantsD5620 Test Method for Evaluating Thin Film Fluid Lubri-cants in a Drain and Dry Mode Using a Pin and Vee BlockTest Machine3D5706 Test Method for Determining Extr
7、eme 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) Test MachineD6425 Test Method for Measuring Friction and Wear
8、 Prop-erties of Extreme Pressure (EP) Lubricating Oils UsingSRV Test Machine2.2 DIN Standards:4DIN 51631:1999-04 Special-boiling-point spirit Re-quirements and testingDIN 51834-3:2008-12 Testing of lubricants Tribologicaltest in translatory oscillation apparatus Part 3: Determi-nation of tribologica
9、l 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 using linear material ratio curve (replacesof DIN 4776:1990: Measu
10、rement 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 against eachother.3.1.2 Hertzian contact pressure, nmagnitude of
11、 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 reportedas maximum value Pmaxin the centre of the contact or asPaverageas average over the total contact area. D4175
12、3.1.3 seizure, nlocalized fusion of metal between therubbing surfaces of the test pieces. D57063.1.3.1 DiscussionSeizure 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 th
13、e chart recorder as permanent rise in thecoefficient of friction from a steady value.3.1.4 wear, ndamage to a solid surface, generally involv-ing progressive loss of material, due to the relative motion1This practice is under the jurisdiction of ASTM Committee D02 on PetroleumProducts and Lubricants
14、 and is the direct responsibility of Subcommittee D02.L0 onEngineering Sciences of High Performance Fluids Solids (Formerly D02.1100).Current edition approved Oct. 1, 2011. Published November 2011. DOI:10.1520/D775511.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact AS
15、TM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.4Available from Deutsches Institut fur Normung e
16、.V.(DIN), Beuth VerlagGmbH, Burggrafenstrae 6, D-10787 Berlin 30, Germany, http:/www.din.de.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.between that surface and a contacting substance or substances.D2714, D2782, D56203.1.5 wear r
17、ate, nthe rate of material removal or dimen-sional change due to wear per unit of exposure parameter; forexample, quantity of 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 Defi
18、nitions of Terms Specific to This Standard:3.2.1 planimetric wear, Wq, nseen in the center of thewear track of the disk perpendicular 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 volumeto the ball or the disk
19、 (flat) at end of test. D5707, D64253.3 Abbreviations:3.3.1 SRV, nSchwingung, Reibung, Verschlei, (Ger-man); oscillating, friction, wear (English translation).4. Summary of Practice4.1 This practice applies to test pieces tribologicallystressed on a SRV test machine typically used in differentASTM (
20、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 diameter onthe ball not consequently indicates materials loss, the amountof material loss and different volumetric material losses can berelated to exact one wear scar diame
21、ter.NOTE 1An extreme and ideal, but frequent case, is the case of alubricant, which fully protects against wear, but a wear scar diameter ismarked only visibly by tribo-chemistry and the wear scar diametercorresponds to the initial Hertzian contact diameter describing the elasticdeformation. By usin
22、g the ball diameter of diameter=10mm,theelastic constants for AISI 52100 (100Cr6H) and FN= 200 N, the initialHertzian contact diameter calculates to 0.374 mm and for FN=300Nis0.428 mm. When now unloading the ball after test, the elastic deformationis released and the initial shape recovers, showing,
23、 for example, no wear,but a marked wear scar, which is reported as wear scar diameter, even no,less or minor wear can be detected 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 t
24、ip profilometer in the centre of the track length (seeFig. 2) and this perpendicular to the sliding direction.4.3.1 The worn or displaced volume (Wv,ball;Wv,flat) can becalculated by numerical methods5, 6, 7from the stylus tip profiledata and assuming an ideal shape of the test specimen.NOTE 2In gen
25、eral, the wear volume is calculated by integrating amultitude of cross section area taken at different lengths of the wear track.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 d
26、erived froma 2D-profilogram by using a stylus tip profilometer.5. Significance and Use5.1 The determination of the wear volume 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
27、 wear on the surface ofthe ball and the wear track as an irreversible loss of material.Users of this test method should determine whether resultscorrelate with field performance or other applications.NOTE 3It is believed, that tactile stylus tip profilometer determinesthe most realistic figure and a
28、re more frequent in use, than it can beachieved by optical profilometers operating in a non-contacting mode.6. Apparatus6.1 Microscope, equipped with a filar eyepiece graduated in0.005-mm division or equipped with a micrometer stagereadable to 0.005-mm. Magnification should be sufficient toallow for
29、 ease of measurement. One to 10 times magnificationhas been found acceptable.6.2 Stylus Tip Profilometer:6.2.1 The stationary working place of the stylus tip profi-lometer should be composed of a stone (granite) base plate, thecolumn, a transverse unit, a skidless tracing arm (skidlesspick-up) and h
30、ave 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. Theresolution of the transverse unit is 0.1 m or better.5Ruff, A. W., “Wear Measurement,” ASM Handbook, Vol 18, 1992, pp.362-369.6Klaffke, D., “Fretting Wear o
31、f Ceramics,” Tribology International, Vol 22,No. 2, 1989, pp. 89-101.7Kalin, M., and Vizintin, J., “Use of Equations for Wear Volume Determinationin Fretting Experiments,” WEAR, 237, 2000, pp. 39-48.NOTER is smaller than R . The wear volumes are marked in blue.FIG. 1 BallComparison of Iso-wear Scar
32、Diameters with WearVolume in Relation to the Initial Radius R and the Radius in theScar R at Test EndFIG. 2 Schematic Illustration of the Segmentation of the WearTrackD7755 1127. Reagents and Materials7.1 Cleaning Solvent, the test balls and disks have to becleaned by a liquid solvent (non-chlorinat
33、ed, non-film form-ing). (WarningFlammable. Health Hazard.)NOTE 4It is recommended to use special boiling point spirit type 2according to DIN 51631:1999.8. Preparation of Apparatus8.1 Most ASTM test methods related to SRV run with a ballsliding on a flat. In consequence and after the test, a wear sca
34、rmarks the ball and a wear track the flat (see Fig. 3).9. Procedure9.1 Cleaning of the SpecimenClean the test ball and diskby 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
35、beakerof the cleaning solvent under ultrasonic vibration for 10 min.Dry the test ball and disk with a clean tissue ensuring nostreaking 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 o
36、f thetrack at least 0.500 mm in order to define the base line of thesurface topography. A tracing speed of 0.15 mm/s has beenfound 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 ma
37、nually the horizontal bar forthe base of the surface topography (see Fig. X1.1). Thesoftware iterates (calculates) the planimetric 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 u
38、sing Eq 1.Wv,ball5p d12 d2264S1R1RD(1)and by using:R 5d2312 Wq, flat(2)where:R = resulting radius of the shape of the wear scarafter the 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 pe
39、rpendicular tothe sliding direction in mm andWq, flat= planimetric wear of the wear track in the middleof the wear track length and seen perpendicularto the sliding 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 ba
40、sisfor 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 wear track on the flat diskWv,flatin mm3is calculated by using Eq 3.Wv,flat5p d42d3 s!2641R1 s Wq,flat(3)where:d3= the total length of wear track in sliding direction inmm
41、,d4= the width of the wear track in mm, ands = stroke in mm.andR 5d4312 Wq,flat(4)where:measured diameter d4=d2in mm.NOTE 5The equations represent an approximation for strokes smallerthan 2 to 2.5 mm and assume thatRRandthewear height of the scaris R.NOTE 6The wear tracks produced by other oscillati
42、ng 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:10.1.1 All parameters used to evaluate th
43、e lubricant asstated in the test method.10.2 Report both wear scar diameter measurements (d1andd2) taken on the ball.FIG. 3 Scheme of Wear Scar (Ball) and Track (Disk, Flat) on theTest SpecimenFIG. 4 Scheme of Variables Used to Calculated the Wear Volumeof Ball and DiskD7755 11310.3 Report the plani
44、metric wear area Wq,flatdetermined inthe wear track of the disk.10.4 Report the calculated wear volumes of ball Wv,ballanddisk 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 we
45、ar volume will dependon the precision of the optical wear diameter measurement andof the planimetric surface area from the stylus 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; oscillat
46、ion; SRV; wear; wearvolumeAPPENDIX(Nonmandatory Information)X1. MEASUREMENTS OF WEAR VOLUMEX1.1 Fig. X1.1 illustrates the setting 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 o
47、f 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
48、a SRV Test DiskD7755 114ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringe
49、ment of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your
