1、Designation: D6425 11D6425 17Standard Test Method forMeasuring Friction and Wear Properties of ExtremePressure (EP) Lubricating Oils Using SRV Test Machine1This standard is issued under the fixed designation D6425; the number immediately following the designation indicates the year oforiginal adopti
2、on 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.INTRODUCTIONThis test method represents the transformation of DIN 51834-2:1997. The DI
3、N working groupimplemented changes at its annual meeting in Munich in September 2000. ASTM Committee D02adopted these modifications as closely as possible. The DIN working group widens the scope of thestandard to accommodate different test conditions and refines repeatability and reproducibility on
4、thebase of four international RR tests. It also introduces the wear volume as a tribological quantity.1. Scope*1.1 This test method covers an extreme pressure (EP) lubricating oils coefficient of friction and its ability to protect againstwear when subjected to high-frequency, linear oscillation mot
5、ion. The procedure is identical to that described in DIN 51834.1.2 This test method can also be used to determine the ability of a non-EP lubricating oil to protect against wear and itscoefficient of friction under similar test conditions.1.3 The values stated in SI units are to be regarded as stand
6、ard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety safety, health, and healthenvironmental pra
7、ctices and determine theapplicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and R
8、ecommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2A295 Specification for High-Carbon Anti-Friction Bearing SteelD235 Specification for Mineral Spirits (Petroleum Spirits) (Hydrocarbon Dry Cleaning Solvent)D4175
9、 Terminology Relating to Petroleum Products, Liquid Fuels, and LubricantsD5706 Test Method for Determining Extreme Pressure Properties of Lubricating Greases Using a High-Frequency, Linear-Oscillation (SRV) Test MachineD7421 Test Method for Determining Extreme Pressure Properties of Lubricating Oils
10、 Using High-Frequency, Linear-Oscillation(SRV) Test MachineD7755 Practice for Determining the Wear Volume on Standard Test Pieces Used by High-Frequency, Linear-Oscillation (SRV)Test MachineE45 Test Methods for Determining the Inclusion Content of SteelG40 Terminology Relating to Wear and Erosion2.2
11、 DIN Standards:3DIN EN ISO 683-17 Heat-treated Steels,steels, alloy steels and free-cutting steels Part steelsPart 17 : Ball and roller bearingsteels1 This test method is under the jurisdiction ofASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility
12、of SubcommitteeD02.L0.11 on TribiologicalTribological Properties of Industrial Fluids and Lubricates.Current edition approved Dec. 1, 2011Oct. 1, 2017. Published March 2012November 2017. Originally approved in 1999. Last previous edition approved in 20102011 asD642505(2010)D6425 11. 1. DOI: 10.1520/
13、D6425-11.10.1520/D6425-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from Deutsches Institut
14、 fr Normung, Beuth Verlag GmbH, Burggrafenstrasse 6, D-10787 Berlin, Germany.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequatel
15、y depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM Inter
16、national, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1DIN 51631:1999 Mineral spirits; special boiling point spirits; requirementsDIN 51834 Tribological Test in the Translatory Oscillation Apparatus (Part 2: Determination of Friction and Wear Data forLubricatin
17、g Oils)DIN EN ISO 13565-2:1998 Geometrical Product Specifications (GPS)Surface Texture: Profile Method; Surfaces havingStratified Functional PropertiesPart 2: Height Characterization using Linear Material Ratio Curve (replacement of DIN4776:1990)3. Terminology3.1 Definitions:3.1.1 break-in, nin trib
18、ology, an initial transition process occurring in newly established wearing contacts, often accompaniedby transients in coefficient of friction or wear rate, or both, that are uncharacteristic of the given tribological systems long termbehavior. (Synonym: run-in, wear-in) G403.1.2 C.L.A., nin measur
19、ing surface finish, the arithmetic average of the absolute distances of all profile points from the meanline for a given distance.43.1.2 coeffcient of friction or f, nin tribology, the dimensionless ratio of the friction force (Ff) between two bodies to thenormal force (Fn) pressing these bodies tog
20、ether. G40 5Ff /Fn! (1)3.1.3 EP lubricating oil, na liquid lubricant containing an extreme pressure (EP) additive3.1.4 extreme pressure (EP) additive, nin a lubricant, a substance that minimizes damage to metal surfaces in contact underhigh stress rubbing conditions. D41753.1.5 Hertzian contact area
21、, nthe apparent area of contact between two nonconforming solid bodies pressed against eachother, as calculated from Hertz equations of elastic deformation. G403.1.6 Hertzian contact pressure, nmagnitude of the pressure at any specified location in a Hertzian contact area, as calculatedfrom Hertzs e
22、quations of elastic deformation.The Hertzian contact pressure can also be calculated and reported as maximum valuePmax in the centre of the contact or as Paverage as average over the total contact area. D74213.1.7 lubricant, nany substance interposed between two surfaces for the purpose of reducing
23、the friction or wear betweenthem. G403.1.8 Pgeom., ngeometric contact pressure describes the load carrying capacity at test end.3.1.9 Ra (C.L.A.), nin measuring surface finish, the arithmetic average of the absolute distances of all profile points from themean line for a given distance.43.1.10 RpK,
24、nReduced peak height according to DIN EN ISO 13565-2:1998. Half the RpK value is the mean height of thepeak sticking out above the core profile section.3.1.11 RvK, nReduced valley height occordingaccording to DIN EN ISO 13565-2:1998. RvK is the mean depth of the valleyreaching into the material belo
25、w the core profile section.3.1.12 Rz (DIN), nin measuring surface finish, the average of all Ry values (peak to valley heights) in the assessment length.43.1.13 wear, ndamage to a solid surface, generally involving progressive loss of material, due to relative motion between thatsurface and a contac
26、ting substance or substances. G403.1.14 Wv, nWearwear volume is the loss of volume to the ball or disk after a test.3.2 Definitions of Terms Specific to This Standard:3.2.1 seizure, nlocalized fusion of metal between the rubbing surfaces of the test pieces. D57063.2.1.1 DiscussionIn this test method
27、, seizure is indicated by a sharp rise in the coefficient of friction, over steady state, of greater than 0.2 for over20 s. 20 s. In severe cases, a stoppage in the motor will occur.3.3 Abbreviations:3.3.1 SRV, nSchwingung, Reibung, Verschleiss, (German); oscillating, friction, wear, (English transl
28、ation). D57064 Amstutz, Hu, “Surface Texture: The Parameters,”Bulletin MI-TP-003-0785, Sheffield Measurement Division, Warner and Swazey, 1985, p. 21.D6425 1724. Summary of Test Method4.1 This test method is performed on an SRV test machine using a test ball oscillated at constant frequency and stro
29、ke amplitudeand under constant load (Fn), against a test disk that has been moistened with the lubricant specimen. The platform to which thetest disk is attached is held at a constant temperature.NOTE 1The frequency of oscillation, stroke length, test temperature, test load, test duration, and test
30、ball and disk material can be varied from thosespecified in this test method. The test ball yields Hertzian point contact geometry. To obtain line or area contact, test pieces of differing configurationscan be substituted for the test ball.4.2 The friction force, Ff, is measured by a piezo-electric
31、device in the test disk assembly. Peak values of coefficient of friction,f, are determined and recorded as a function of time.4.3 After a preset test period, the test machine and chart recorder are stopped and the wear scar on the ball is measured. If aprofilometer is available, a trace of the wear
32、scar on the test disk can also be used to obtain additional wear information.5. Significance and Use5.1 This test method can be used to determine anti-wear properties and coefficient of friction of EP lubricating oils at selectedtemperatures and loads specified for use in applications in which high-
33、speed vibrational or start-stop motions are present forextended periods of time under initial high Hertzian point contact pressures. It has found application as a screening test forlubricants used in gear or cam/follower systems. Users of this test method should determine whether results correlate w
34、ith fieldperformance or other applications.6. Apparatus6.1 SRV Test Machine5(seeillustrated Fig. 1),in Figs. 1-4, consists of an oscillation drive, a test chamber (see Fig. 2 and Fig. 4),and a loading device6 with a servomotor and a load cell. The machine is operated by a control device for the osci
35、llating drive, atimer, a load control, a frequency control, a stroke control, a data amplifier to determine the friction coefficient, and a switch anda controller for the heating. An oscilloscope may be used for monitoring. Friction coefficients are recorded in relation to time bya chart recorder, o
36、r by data acquisition in a computer.6.1.1 On the firmly mounted receiving block (1) in the test chamber (see Fig. 2 and Fig. 34), there is a piezoelectric device (2)to measure the friction force, Ff, and the friction coefficient, f; the holder for the test disk (3) with a thermostat-controlled elect
37、ricalresistance heating element (4); a resistance thermometer (5); the oscillation drive rods (6); an exchangeable holder for the test ball(7); and the load rods of the loading device (8).6.1.2 The design of the receiving block for the test disk should be such that it has integrated cooling coils, o
38、r that cooling coilsare wound roundaround it, so that the receiving block must be capable to maintaining test temperatures down to +233K.+233 K.The test disk (9) and the test ball (10) are inserted into their respective holders (3, 4) (see Fig. 2 and Fig. 34).6.1.3 Disks are generally used as the lo
39、wer test piece. Balls, cylinders, rings, or specialized shapes may be used, withappropriate holders, as the upper test piece (see Fig. 45).5 The sole source of supply known to the committee at this time is Optimol Instruments Prftechnik GmbH, Friedenstrasse 10, D81671Westendstr. 125, D-80339 Munich,
40、Germany. If you are aware of alternative suppliers, please provide this information to ASTM Headquarters. Your comments will receive careful consideration at a meetingof the responsible technical committee,1 which you may attend.6 Optimol Instruments supplies an upgrade kit to allow older machines t
41、o operate with 1600 N, 1600 N, if needed.FIG. 1 SRV Test Machine (Model III)D6425 1736.2 Microscope, equipped with a filar eyepiece graduated in 0.005-mm0.005 mm divisions or equipped with a micrometre stagereadable to 0.005 mm. 0.005 mm. Magnification should be sufficient to allow for ease of measu
42、rement.6.3 Syringe, suitable for applying 0.3 mL 0.3 mL of the lubricating oil under test.6.4 Tweezers, straight, round, about 200-mm200 mm long, with non-marring tips.6.5 Torque Wrench, initial torque 0.50.5 Nm to 5 Nm.5 Nm.FIG. 2 Test Chamber Elements of SRV III1. Oscillation drive rod 6. Electric
43、al resistance heater2. Test ball holder 7. Resistance thermometer3. Load rod 8. Test disk holder4. Test ball 9. Piezoelectric measuring device5. Test disk 10. Receiving blockFIG. 3 Test Machine (Model IV)D6425 1746.6 Ultrasonic Cleaner.1. Receiving Block 6. Oscillation Drive Rod2. Piezoelectric Meas
44、uring Device 7. Test Ball Holder3. Test Disk Holder 8. Load Rod4. Electrical Resistance Heater 9. Test Disk5. Resistance Thermometer 10. Test Ball1. Base of the receiving block 7. Upper specimen holder2. Piezo force measurement elements 8. Drive rods of the load unit3. Supporting surface (head plate
45、) of the receiving block 9. Test disk4. Lower specimen holder 10. Test ball5. Position of the electrical resistance heating and resis-tance thermometerFn Normal force (test load)6. Oscillation drive rods Ff Friction forceFIG. 34 Test Chamber Elements of SRV Models IV and VFIG. 45 Test Pieces and Hol
46、ders for Standard Tribological ContactsD6425 1757. Reagents and Materials7.1 Test Balls,7AISI 52100 Steel, 60 6 2 HRC hardness, 0.025 6 0.005-m C.L.A. 0.025 m 6 0.005 m Ra (C.L.A.) surfacefinish, 10-mm10 mm diameter.7.2 Test Disk,7vacuum arc remelted (VAR)AISI 52100 steel with an inclusion rating us
47、ing method D, TypeA, as severity levelnumber of 0,5 according to Test Methods E45 and Specification A295 or a inclusion sum value K1 10 according to DIN EN ISO683-17 and spherodized annealed to obtain globular carbide, 62 6 1 HRC hardness, the surfaces of the disk being lapped and freeof lapping raw
48、 materials. The topography of the disk will be determined by four values: 0.5 m 0.5 m 20 sCoefficient of friction, f (cut-off value for one-off increase of level): 0.357 ASM Handbook, “Friction, Lubrication, and Wear Technology,” Vol 18, October 1992.D6425 1768.2.3 Test parameters:Frequency: 50 HzSt
49、roke: 1.00 mmTemperature: for example, 50 C or 80 C or 120 CPre-load: 50 N for 30 sTest load: running-in under 50 N for 30 s, then constant load of 300 N8.2.4 Sample rates for result-relevant measurement channels:Coefficient of friction, f: #32 msStroke: #2 sTest load: #2 sFrequency: #2 sTemperature: #2 sNOTE 7For SRV V models, it is recommended to do one sampling per period (that is, 20 ms) for coefficient of friction and stroke.9. ProcedureProcedure for All SRV Models9.1 Installation of the Test Pieces and Lubricating Oil S
