1、Designation: D7594 11D7594 16Standard Test Method forDetermining Fretting Wear Resistance of LubricatingGreases Under High Hertzian Contact Pressures Using aHigh-Frequency, Linear-Oscillation (SRV) Test Machine1This standard is issued under the fixed designation D7594; the number immediately followi
2、ng 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 c
3、overs a procedure for determining the lubricating action of greases in order to prevent “fretting” wearunder linear oscillation with associated low strokes and high Hertzian contact pressures under high-frequency linear-oscillationmotion using the SRV test machine. By performing additional, nonmanda
4、tory extreme-pressure tests in accordance with TestMethod D5706, the test grease should be shown to be able to withstand a Hertzian contact pressure of at least 2200 MPa withoutadhesive failure.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are includ
5、ed in this standard.1.3 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 and health practices and determine the applicability of regulatorylimitations prior to u
6、se.2. Referenced Documents2.1 ASTM Standards:2A295/A295M Specification for High-Carbon Anti-Friction Bearing SteelD217 Test Methods for Cone Penetration of Lubricating GreaseD235 Specification for Mineral Spirits (Petroleum Spirits) (Hydrocarbon Dry Cleaning Solvent)D4175 Terminology Relating to Pet
7、roleum Products, Liquid Fuels, and LubricantsD5706 Test Method for Determining Extreme Pressure Properties of Lubricating Greases Using a High-Frequency, Linear-Oscillation (SRV) Test MachineD6425 Test Method for Measuring Friction and Wear Properties of Extreme Pressure (EP) Lubricating Oils Using
8、SRV TestMachineD7421 Test Method for Determining Extreme Pressure Properties of Lubricating Oils 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 Metho
9、ds for Determining the Inclusion Content of SteelG40 Terminology Relating to Wear and Erosion2.2 DINOther Standards:3DIN 51834-3:2008-12 Testing of lubricants Tribological test in translatory oscillation apparatus Part LubricantsTribological Test in Translatory Oscillation ApparatusPart 3: Determina
10、tion of tribological behaviourTribologicalBehaviour of materialsMaterials in cooperationCooperation with lubricantsLubricantsDIN 51631:1999 Special-boiling-point spirits - Requirements and testingSpecial-Boiling-Point SpiritsRequirements andTesting1 This test method is under the jurisdiction ofASTM
11、Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of SubcommitteeD02.G0.04 on Functional Tests - Tribology.Current edition approved Dec. 1, 2011Dec. 1, 2016. Published March 2012March 2017. Originally approved in 2010. Last previous edition approved i
12、n 20102011 asD7594D7594 11.10. DOI:10.1520/D7594-11. DOI:10.1520/D7594-16.2 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
13、ASTM website.3 Available from Available from Beuth Verlag GmbH (DIN- DIN Deutsches Institut fur Normung e.V.), Burggrafenstrasse 6, 10787, Berlin, Germany, http:/www.en.din.de.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what cha
14、nges have been made to the previous version. Becauseit may not be technically possible to adequately 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 offi
15、cial document.*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 States1DIN EN ISO 683-17 Heat-treated steels, alloy steels and free-cutting steels - Part Heat-Treated Steels, All
16、oy Steels andFree-Cutting SteelsPart 17: Ball and roller bearing steels (replaces DIN 17230-1980)Roller Bearing Steels Replaces DIN17230-1980DIN EN ISO 13565-2:1998 Geometrical Product Specifications (GPS) - Surface texture: Profile method - Surfaces havingstratified functional properties - Part 2:
17、Height characterization using the linear material ratio curve (replaces DIN4776-1990)(GPS)Surface Texture: Profile MethodSurfaces Having Stratified Functional PropertiesPart 2: HeightCharacterization Using the Linear Material Ratio Curve Replaces DIN 4776-19903. Terminology3.1 Definitions:3.1.1 brea
18、k-in, nin tribology, 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. G403.1.2 coeffcient of friction, or , ni
19、n tribology, the dimensionless ratio of the friction force (F) between two bodies to thenormal force (N) pressing these bodies together. G403.1.3 Hertzian contact area, napparent area of contact between two nonconforming solid bodies pressed against each other,as calculated from HertzHertzs equation
20、s of elastic deformation. G403.1.4 Hertzian contact pressure, nmagnitude of the pressure at any specified location in a Hertzian contact area, as calculatedfrom Hertzs equations of elastic deformation.The Hertzian contact pressure can also be calculated and reported as maximum valuePmax in the centr
21、e of the contact or as Paverage as average over the total contact area. D74213.1.5 lubricant, nany material interposed between two surfaces that reduces the friction or wear between them. D41753.1.6 lubricating grease, na semifluidsemi-fluid to solid product of a dispersion of a thickener in a liqui
22、d lubricant. D2173.1.6.1 DiscussionThe dispersion of the thickener forms a two-phase system and immobilizes the liquid lubricant by surface tension and otherphysical forces. Other ingredients are commonly included to impart special properties.3.1.7 Ra (C.L.A.), nin measuring surface finish, the arit
23、hmetic average of the absolute distances of all profile points from themean line for a given distance.3.1.7.1 DiscussionC.L.A. means center line average, and it is a synonym to Ra. Amstutz, p. 21Amstutz43.1.8 Rpk, nReducedreduced peak height according to DIN EN ISO 13565-2:1998. Rpk is the mean heig
24、ht of the peak stickingout above the core profile section.3.1.9 Rvk, nReducedreduced valley height according to DIN EN ISO 13565-2:1998. Rvk is the mean depth of the valleyreaching into the material below the core profile section.3.1.10 Rz (DIN), nin measuring surface finish, the average of all Ry v
25、alues (peak to valley heights) in the assessment length.Amstutz, pp. 29, 31Amstutz53.1.11 thickener, nin lubricating grease, a substance composed of finely divided particles dispersed in a liquid lubricant toform the products structure. D2173.1.11.1 DiscussionThe thickener can be fibers (such as var
26、ious metallic soaps) or plates or spheres (such as certain non-soap thickeners) which areinsoluble or, at most, only very slightly soluble in the liquid lubricant. The general requirements are that the solid particles beextremely small, uniformly dispersed, and capable of forming a relatively stable
27、, gel-like structure with the liquid lubricant.3.2 Definitions of Terms Specific to This Standard:3.2.1 extreme pressure, adjin lubrication, characterized by metal surface in contact under high-stress rubbing conditions.3.2.2 fretting wear, nwear arising as a result of fretting. Small amplitude osci
28、llatory motion, usually tangential, between twosolid surfaces in contact.4 Amstutz, Hu, “Surface Texture: The Parameters,” Bulletin MI-TP-0030785, Sheffield Measurement Division, Warner and Swasey, 1985, p. 21.5 Amstutz, Hu, “Surface Texture: The Parameters,” Bulletin MI-TP-0030785, Sheffield Measur
29、ement Division, Warner and Swasey, 1985, p. 29, 31.D7594 1623.2.3 seizure, nlocalized fusion of metal between the rubbing surfaces of the test pieces. D57063.2.3.1 DiscussionIn this test method, seizure is indicated by a sharp rise in the coefficient of friction, over steady state, of greater than 0
30、.2 for over20 s, or a coefficient of friction 0.35 or by any examples shown in Test Method D5706 and D7421). If any of these conditionsoccur, the test is not valid. (These criteria were believed to be right, because this standard is related to greases.) The evidence ofadhesive wear morphologies shou
31、ld be controlled by micro-optical examination of the wear scar and track. In severe cases, astoppage in the motor will occur.3.3 Abbreviations:3.3.1 SRV, nSSchwingung,chwingung, RReibung,eibung, VVerschleierschlei (German); oscillating, friction, wear (Englishtranslation).4. Summary of Test Method4.
32、1 This test method is performed on an SRV test machine using a steel test ball oscillating under constant frequency, shortstroke amplitude and under constant load (Fn), against a stationary steel test disk with a grease lubricant between them in orderto determine the coefficient of friction and wear
33、 scar diameter.4.2 For the non-mandatorynonmandatory extreme pressure test (see Appendix X1), the test load is increased in 100-N100 Nincrements until seizure occurs (see Test Method D5706). The load, immediately prior to the load at which seizure occurs, ismeasured and reported.NOTE 1Test frequency
34、, stroke length, temperature, and ball and disk material can be varied to simulate field conditions. The test ball yieldspoint-contact geometry. To obtain line or area contact, test pieces of differing configurations can be substituted for the test balls.4.3 The friction force, Ff, is measured by a
35、piezo-electric device in the test disk assembly. Peak values of coefficient of friction,f, are determined and recorded as a function of time for SRV I and II models. SRV III and IV models can display the hysteresis(Friction(friction force or coefficient of friction over stroke length) and save test
36、data electronically.4.4 After a preset test period, the test machine and chart recorder stopped and the wear scar on the ball is measured. If aprofilometer is available, a trace of the wear track on the test disk and the wear scar of the ball (See DIN 51834-3 and AppendixX1) can also be used to obta
37、in additional wear information. Wearinformation (wear volume in mm3 and wear rate of disk and ballin mm3/Nm).5. Significance and Use5.1 This test method can be used to determine anti-wear properties and coefficient of friction of greases in order to prevent“fretting” wear under linear oscillation wi
38、th associated low strokes and high Hertzian contact pressures at selected temperaturesand loads specified for use in applications in which induced, high-speed vibrational motions are present for extended periods oftime. It has found application as a screening test for grease lubricants used in ball
39、and roller bearings, roller or ball screw (spindle)drives or side shaft systems (Tripode or Rzeppa type) for example, so-called constant velocity (CV) joints. Users of this test methodshould determine whether results correlate with field performance or other applications.6. Apparatus6.1 SRV Test Mac
40、hine6, Illustratedillustrated in Fig. 1Figs. 1-4 and Fig. 2.7. Reagents and Materials7.1 Test Balls6, 52100 steel, 6060 HRC 6 2 Rc hardness, 0.025 6 0.005-mHRC, 0.025 m 6 0.005 m Ra surface finish,10-mm10 mm diameter.7.2 Lower Test Disk6, Vacuum arc remelted (VAR) AISI 52100 steel with an inclusion
41、rating using Method D, Type A, asseverity level number of 0.5 in accordance with Test Methods E45 and Specification A295/A295M or an inclusion sum value K1 10 in accordance with DIN EN ISO 683-17 and spherodized annealed to obtain globular carbide, 60 6 2 Rc hardness, 60 HRC6 2 HRC, the surfaces of
42、the disk being lapped and free of lapping raw materials. The topography of the disk will be determinedby four values, 24-mm24 mm diameter by 7.85 mm thick:0.5 m 20 sCoefficient of friction, f (cut-off value for one-off increase of level): 0.358.8.3 Test parameters:Frequency: 50 HzStroke: 0.30 mmTemp
43、erature: for example, 50 C, 80 C or 120 CPre-load: 50 N for 30 sTest load: running-in under 50 N for 30 s, then constant load of 100 NTest duration 240.5 min8.8.4 Sample rates for result-relevant measurement channels:Coefficient of friction, f: #32 msStroke: #2 sTest load: #2 sFrequency: #2 sTempera
44、ture: #2 s.NOTE 6For SRV V models, it is recommended to do one sampling per period (that is, 20 ms) for coefficient of friction and stroke.9. Procedure9.1 Installation of the Test Pieces and Lubricating Oil Specimen in the Test Chamber:9.1.1 Using solvent resistant solvent-resistant gloves, clean th
45、e test ball, ball holder, and disk by wiping the surfaces withlaboratory tissue soaked with the cleaning solvent (single boiling point spirit type 2-A in accordance with DIN 51631:1999.(WarningThis mixture is flammable and a health hazard.) Repeat wiping until no dark residue appears on the tissue.
46、Immersethe test ball and disk in a beaker of the cleaning solvent under ultrasonic vibration for 10 min. Dry the test ball and disk with aclean tissue to ensure no streaking occurs on the surface.9.1.2 Ensure that the machine is unloaded (indicated by a load reading of 13 or 14N), and install the ba
47、ll holder (upperspecimen holder).test load unit is in the release position (refer to operating manual for details).9.1.3 Place the grease caliper with 11.5 mm in height on the cleaned disc. Fill the opening of the grease caliper with grease.Remove any excess grease by means of a spatula. Remove the
48、grease caliper by lifting it upwards. Fasten the disc in the specimenholder.9.1.4 Place the cleaned test ball on the top and in the middle of the lubricating grease specimen so that the lubricating greasemakes a circular symmetric pad between the test ball and disk.9.1.5 Tighten the fastening screw
49、until resistance just begins.9.2 Test Run Procedure for SRV III, IV, and V Models:9.2.1 Open theAssistant for starting a test in the SRV control software. Select the created set-point profile and, if necessary (forexample, SRV V), the data logger configuration and proceed through the Assistant until the pre-load has been applied.9.2.2 Set the test load unit to 50 N and release and retighten the ball and disk clamps to a torque of 2.5 Nm.9.2.3 The heater control starts automatically and heats up to the pre-set and d
