1、Designation: D 6425 05An American National StandardStandard Test Method forMeasuring Friction and Wear Properties of ExtremePressure (EP) Lubricating Oils Using SRV Test Machine1This standard is issued under the fixed designation D 6425; the number immediately following the designation indicates the
2、 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 (e) indicates an editorial change since the last revision or reapproval.INTRODUCTIONThis test method represents the transformation of
3、DIN 51834-2:1997. The DIN 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
4、 and reproducibility on thebase of four international RR tests. It also introduces the wear volume as a tribological quantity.1. Scope1.1 This test method covers an extreme pressure (EP)lubricating oils coefficient of friction and its ability to protectagainst wear when subjected to high-frequency,
5、linear oscilla-tion motion. The procedure is identical to that described inDIN 51834.1.2 This test method can also be used to determine theability of a non-EP lubricating oil to protect against wear andits coefficient of friction under similar test conditions.1.3 The values stated in SI units are to
6、 be regarded as thestandard. The values given in parentheses are for informationonly.1.4 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 an
7、d determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2A 295 Specification for High-Carbon Anti-friction BearingSteelD 4175 Terminology Relating to Petroleum, PetroleumProducts, and LubricantsE45 Test Methods for Determining the Inclusion Con
8、tentof SteelG40 Terminology Relating to Wear and Erosion2.2 DIN Standards:3DIN EN ISO 683-17 Heat-treated Steels, alloy steels andfree-cutting steels Part 17 : Ball and roller bearing steelsDIN 51631:1999 Mineral spirits; special boiling point spir-its; requirementsDIN 51834 Tribological Test in the
9、 Translatory OscillationApparatus (Part 2: Determination of Friction and WearData for Lubricating Oils)DIN EN ISO 13565-2:1998 Geometrical Product Specifica-tions (GPS)Surface Texture: Profile Method; Surfaceshaving Stratified Functional PropertiesPart 2: HeightCharacterization using Linear Material
10、 Ratio Curve (re-placement of DIN 4776:1990)2.3 ISO Standards:4ISO 1250:1972 Mineral Solvents for Paints, White Spiritsand Related Hydrocarbon Solvents3. Terminology3.1 Definitions:3.1.1 break-in, nin tribology, an initial transition processoccurring in newly established wearing contacts, often acco
11、m-panied by transients in coefficient of friction or wear rate, orboth, that are uncharacteristic of the given tribological sys-tems long term behavior. (Synonym: run-in, wear-in) G403.1.2 C.L.A., nin measuring surface finish, the arithmeticaverage of the absolute distances of all profile points fro
12、m themean line for a given distance.51This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.L0 on Industrial Lubricants.Current edition approved July 1, 2005. Published August 2005. Originallyapproved
13、in 1999. Last previous edition approved in 2002 as D 642502.2For 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.3
14、Available from Deutsches Institut fr Normung, Beuth Verlag GmbH, Burg-grafenstrasse 6, D-10787 Berlin, Germany.4Available from International Organization for Standardization (ISO), 1 rue deVaremb, Case postale 56, CH-1211, Geneva 20, Switzerland.5Amstutz, Hu, “Surface Texture: The Parameters,” Bulle
15、tin MI-TP-003-0785,Sheffield Measurement Division, Warner and Swazey, 1985, p. 21.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.3 coeffcient of friction or f, nin tribology, thedimensionless ratio of the friction force (Ff) bet
16、ween twobodies to the normal force (Fn) pressing these bodies together.G40 5 Ff/ Fn! (1)3.1.4 EP lubricating oil, na liquid lubricant containing anextreme pressure (EP) additive3.1.5 extreme pressure (EP) additive, nin a lubricant,asubstance that minimizes damage to metal surfaces in contactunder hi
17、gh stress rubbing conditions. D 41753.1.6 Hertzian contact area, nthe apparent area of contactbetween two nonconforming solid bodies pressed against eachother, as calculated from Hertz equations of elastic deforma-tion. G403.1.7 Hertzian contact pressure, nthe magnitude of thepressure at any specifi
18、ed location in a Hertzian contact area, ascalculated from Hertz equations of elastic deformation.G403.1.8 lubricant, nany substance interposed between twosurfaces for the purpose of reducing the friction or wearbetween them. G403.1.9 Pgeom., ngeometric contact pressure describes theload carrying cap
19、acity at test end.3.1.10 RpK, nReduced peak height according to DIN ENISO 13565-2:1998. RpK is the mean height of the peaksticking out above the core profile section.3.1.11 RvK, nReduced valley height occording to DINEN ISO 13565-2:1998. RvK is the mean depth of the valleyreaching into the material
20、below the core profile section.3.1.12 Ry, nin measuring surface finish, the verticaldistance between the top of the highest peak and the bottom ofthe deepest valley in one sampling length of the roughnessprofile.53.1.13 Rz, nin measuring surface finish, the average of allRy values (peak to valley he
21、ights) in the assessment length.53.1.14 wear, ndamage to a solid surface, generally in-volving progressive loss of material, due to relative motionbetween that surface and a contacting substance or substances.G403.1.15 Wv, nWear volume is the loss of volume to the ballafter a test.3.2 Definitions of
22、 Terms Specific to This Standard:3.2.1 seizure, nstopping of the relative motion as theresult of interfacial friction. Discussion: the seizure criteria arethe stoppage of the machine, a sharp increase of the coefficientof friction of +0.2 for over 20 seconds or a coefficient offriction 0.35. If any
23、of these conditions occur the test is notvalid. (These criteria were believed to be right, because thisstandard is related to liquid lubricants).64. Summary of Test Method4.1 This test method is performed on an SRV test machineusing a test ball oscillated at constant frequency and strokeamplitude an
24、d under constant load (Fn), against a test disk thathas been moistened with the lubricant specimen. The platformto which the test disk is attached is held at a constanttemperature.NOTE 1The frequency of oscillation, stroke length, test temperature,test load, test duration, and test ball and disk mat
25、erial can be varied fromthose specified in this test method. The test ball yields Hertzian pointcontact geometry. To obtain line or area contact, test pieces of differingconfigurations can be substituted for the test ball.4.2 The friction force, Ff, is measured by a piezo-electricdevice in the test
26、disk assembly. Peak values of coefficient offriction, f, are determined and recorded as a function of time.4.3 After a preset test period, the test machine and chartrecorder are stopped and the wear scar on the ball is measured.If a profilometer is available, a trace of the wear scar on the testdisk
27、 can also be used to obtain additional wear information.5. Significance and Use5.1 This test method can be used to determine anti-wearproperties and coefficient of friction of EP lubricating oils atselected temperatures and loads specified for use in applica-tions in which high-speed vibrational or
28、start-stop motions arepresent for extended periods of time under initial high Hertzianpoint contact pressures. It has found application as a screeningtest for lubricants used in gear or cam/follower systems. Usersof this test method should determine whether results correlatewith field performance or
29、 other applications.6. Apparatus6.1 SRV Test Machine7(see Fig. 1), consists of an oscilla-tion drive, a test chamber (see Fig. 2), and a loading device8with a servomotor and a load cell. The machine is operated bya control device for the oscillating drive, a timer, a load control,a frequency control
30、, a stroke control, a data amplifier todetermine the friction coefficient, and a switch and a controllerfor the heating. An oscilloscope may be used for monitoring.6ASM Handbook, “Friction, Lubrication, and Wear Technology,” Vol 18,October 1992.7The sole source of supply known to the committee at th
31、is time is OptimolInstruments Prftechnik GmbH, Friedenstrasse 10, D 81671 Munich, Germany. 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
32、 attend.8Optimol Instruments supplies an upgrade kit to allow older machines to operatewith 1600 N, if needed.FIG. 1 SRV Test MachineD6425052Friction coefficients are recorded in relation to time by a chartrecorder, or by data acquisition in a computer.6.1.1 On the firmly mounted receiving block (1)
33、 in the testchamber (see Fig. 3), there is a piezoelectric device (2) tomeasure the friction force, Ff, and the friction coefficient, f; theholder for the test disk (3) with a thermostat-controlledelectrical resistance heating element (4); a resistance thermom-eter (5); the oscillation drive rods (6
34、); an exchangeable holderfor 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 diskshould be such that it has integrated cooling coils, or thatcooling coils are wound round it, so that the receiving blockmust be capable to maintaining
35、 test temperatures down to+233K. The test disk (9) and the test ball (10) are inserted intotheir respective holders (3, 4) (see Fig. 3).6.1.3 Disks are generally used as the lower test piece. Balls,cylinders, rings, or specialized shapes may be used, withappropriate holders, as the upper test piece
36、(see Fig. 4).6.2 Microscope, equipped with a filar eyepiece graduated in0.005-mm divisions or equipped with a micrometre stagereadable to 0.005 mm. Magnification should be sufficient toallow for ease of measurement.6.3 Syringe, suitable for applying 0.3 mL of the lubricatingoil under test.6.4 Tweeze
37、rs, straight, round, about 200-mm long, withnon-marring tips.6.5 Torque Wrench, initial torque 0.5 to 5 Nm.6.6 Ultrasonic Cleaner.7. Reagents and Materials7.1 Test Balls,6AISI 52100 Steel, 60 6 2 HRC hardness,0.025 6 0.005-m C.L.A. surface finish, 10-mm diameter.7.2 Test Disk,6vacuum arc remelted (V
38、AR) AISI 52100steel with an inclusion rating using method D, Type A, asseverity level number of 0,5 according to Test Methods E45and Specification A 295 or a inclusion sum value K1 # 10according to DIN EN ISO 683-17 and spherodized annealed toobtain globular carbide, 62 6 1 HRC hardness, the surface
39、s ofthe disk being lapped and free of lapping raw materials. Thetopography of the disk will be determined by four values: 0.5m 55 single results per test oil. (Test conditions: FN= 300 N; T = 50C; t = 120 min; Dx = 1 mm; nn = 50 Hz; lappedAISI52100-disks; polished AISI52100-balls, = 10 mm)TABLE X1.2
40、 7th International Round Robin Test2003AYear RR2003 RR2003 RR2000Test Oils Industrial Oil B VG 220 Industrial Oil B VG 220 Industrial Oil B VG 220Temperature 120C 80C 50CStatistical Quantities(D2PP)Coefficient of frictionfENDWear scar diameterof the ballWK-averagemmCoefficient of frictionfENDWear sc
41、ar diameterof the ballWK-averagemmCoefficient of frictionfENDWear scar diameterof the ballWK-averagemmDegree of Freedom 23 27 24 27 39 45Mean 0.0986 0.4835 0.1038 0.403 0.1105 0.47397Standard Deviation 60.00839 60.0189 60.00699 60.0257 60.00891 60.0403Reproducibility (R) 0.0246(set point: #0.03)0.05
42、48(set point: #0.2)0.0195(set point: #0.03)0.0747(set point: #0.2)0.02540(set point: #0.03)0.1146(set point: #0.2)Repeatability (r) 0.00439(set point: #0.01)0.0277(set point: #0.07)0.00491(set point: #0.01)0.0326(set point: #0.07)0.00772(set point: #0.01)0.6680(set point: #0.07)AStatistical analysis using ASTM D2PP software 43 single results per test oil. (Test conditions: FN= 300 N; T = 50C; t = 120 min; Dx = 1 mm; nn = 50 Hz; lappedAISI52100-disks; polished AISI52100-balls, = 10 mm)D6425057
