1、Designation: D8227 18Standard Test Method forDetermining the Coefficient of Friction of SynchronizerLubricated by Mechanical Transmission Fluids (MTF) Usinga High-Frequency, Linear-Oscillation (SRV) Test Machine1This standard is issued under the fixed designation D8227; the number immediately follow
2、ing 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. Scope1.1 This test method c
3、overs a procedure for determining thecoefficient of friction of lubricants (fluids) tribologically inter-acting with materials used in synchronizers in mechanicaltransmission (MT) gears under high-frequency linear-oscillation motion using the SRV test machine. A flat arealcontact geometry is applied
4、.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.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 app
5、ro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theD
6、evelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D235 Specification for Mineral Spirits (Petroleum Spirits)(Hydrocarbon Dry Cleaning Solvent)D4175 Terminolog
7、y Relating to Petroleum Products, LiquidFuels, and LubricantsD5579 Test Method for Evaluating the Thermal Stability ofManual Transmission Lubricants in a Cyclic DurabilityTestD5706 Test Method for Determining Extreme PressureProperties of Lubricating Greases Using a High-Frequency, Linear-Oscillatio
8、n (SRV) Test MachineD7421 Test Method for Determining Extreme PressureProperties of Lubricating Oils Using High-Frequency,Linear-Oscillation (SRV) Test MachineG40 Terminology Relating to Wear and Erosion2.2 Other Standards:DIN 51631 Special-boiling-point spiritsRequirements andtesting3DIN EN ISO 135
9、65-2 Geometrical Product Specifications(GPS)Surface texture: Profile methodSurfaces hav-ing stratified functional propertiesPart 2: Height char-acterization using linear material ratio curve3DIN EN 170223 Heat treatment of ferrous materials; heattreatment methods; case hardening3CEC L-66-99 Evaluati
10、on of synchronizer loading param-eters and their ability to predict failure4GB/T 3077-2015 Alloy structural steel5YS/T 669-2013 Copper alloy tube of extruded product forsynchronizer rings6TL-VW084 (1993) Kupfer-Zink-Legierungen Werkstoffanforderungen (Copper-Zinc alloysMaterial require-ments)73. Ter
11、minology3.1 Definitions:3.1.1 break-in, nin tribology, an initial transition processoccurring in newly established wearing contacts, often accom-panied by transients in coefficient of friction or wear rate, or1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liq
12、uid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.L0 on Industrial Lubricants and Engineering Sciences of HighPerformance Fluids and Solids.Current edition approved Oct. 1, 2018. Published November 2018. DOI:10.1520/D8227-18.2For referenced ASTM standards, visit the ASTM
13、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.3Available from Beuth Verlag GmbH (DIN Deutsches Institut fr Normunge.V.), Burggrafenstrasse 6, 10787 Berlin
14、, Germany, http:/www.en.din.de4Available from Coordinating European Council (CEC), Services provided byKellen Europe, Avenue Jules Bordet 142 - 1140, Brussels, Belgium, http:/www.cectests.org.5Available from Standardization Administration of China, No. 9 MadianDonglu, Haidian District, Beijing 10008
15、8, P.R. China.6Available as a standard of nonferrous industry from Standardization Adminis-tration of China, No. 9 Madian Donglu, Haidian District, Beijing 100088, P.R.China.7Available from Volkswagen AG, corporate IP, post stop 1770, D-38346Wolfsburg, Germany, .Copyright ASTM International, 100 Bar
16、r Harbor Drive, PO Box 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 Recomm
17、endations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1both, which are uncharacteristic of the given tribologicalsystems long-term behavior. G403.1.2 coeffcient of friction, or , nin tribology, thedimensionless ratio of the friction force (F) between twobodies
18、to the normal force (N) pressing these bodies together.G403.1.3 lubricant, nany material interposed between twosurfaces that reduces the friction or wear between them. D41753.1.4 carburization, ncarburizing is not defined in theASTM Dictionary of Engineering Science and Technology, butis defined in
19、DIN EN 17022-3 “Heat treatment of ferrousmaterials; heat treatment methods; case hardening”.3.1.5 Ra (C.L.A.), nin measuring surface finish, the arith-metic average of the absolute distances of all profile pointsfrom the mean line for a given distance.83.1.6 Rpk, nreduced peak height according to DI
20、N ENISO 13565-2; Rpk is the mean height of the peak sticking outabove the core profile section.3.1.7 Rvk, nreduced valley height according to DIN ENISO 13565-2; Rvk is the mean depth of the valley reaching intothe material below the core profile section.3.1.8 Rz (DIN), nin measuring surface finish,
21、the averageof all Ry values (peak to valley heights) in the assessmentlength.93.2 Definitions of Terms Specific to This Standard:3.2.1 metal specimen, nrepresented by the lower speci-men disk in manganese brass alloys, but also friction layers inthermally sprayed molybdenum coatings, sinter iron, pa
22、per andcarbon fiber tapes are in use.3.2.2 seizure, nlocalized fusion of metal between therubbing surfaces of the test pieces. D57063.2.2.1 DiscussionIn this test method, seizure is indicatedby a sharp rise in the coefficient of friction, over steady state,of greater than 0.3 for over 20 s. In sever
23、e cases, a stoppage inthe motor will occur (for example, see Test Methods D5706and D7421).3.3 Acronyms:3.3.1 SRV, nSchwingung, Reibung, Verschlei (German);oscillating, friction, wear (English translation).3.3.2 UNS, nthe Unified Numbering System (UNS) is anaccepted alloy designation system in North
24、America.4. Summary of Test Method4.1 This test method is performed on SRV test machineusing a areal flat-on-flat geometry oscillating at 50 Hz againsta steel test disk with lubricant (grease) between them. Test loadis fixed to 260 N (corresponding to a geometrical contactpressure of 3.1 MPa) using a
25、 test temperature of 60 C and astroke of 1.0 mm during a test time of 2 h. This test is limitedto SRV Models 4 and 5.NOTE 1Synchronizer rings operate typically under geometric contactpressures from 2 MPa to 6 MPa.NOTE 2Test frequency, stroke length, temperature, and materialsand/or coatings used as/
26、on disk and flat material can be varied to simulatefield conditions.NOTE 3This test runs in the SRV Models 4 and 5 models horizontallyand untilted. SRV Models 4 and 5 can be equipped with a maximum testload unit of 2500 N.5. Significance and Use5.1 This test method can be used to quickly determine t
27、helubricating ability of fully-formulated lubricants used as me-chanical transmission fluids (MTF) to display a frictionalbehavior against materials used in synchronizers of mechanicalgears in automotive vehicles. This test method has found to becomplementary to bench tests (for example, Test Method
28、D5579 and CEC L-66-99) by using the present test conditions.This test method is a material and application oriented ap-proach based on inputs from field experiences for characteriz-ing the frictional behavior (coefficient of friction (cof) usingrandom, discrete, and constant parameter combinations a
29、s seenin field experiences. Users of this test method should determinewhether results correlate with field performance or otherapplications prior to commercialization.6. Apparatus6.1 SRV Test Machine,10illustrated in Figs. 1 and 2.7. Reagents and Materials7.1 Flat ring disk in carburized 20CrMnTi (s
30、imilar to20MnCr5 and SAE 5120) bearing steel in =200.05 mm outerdiameter oil quenched from 800 C 6 10 C and tempered at180 C 6 10 C during 8 h followed by air cooling to 60 62 HRC. The contact face has an inner cavity with a diameter of17 mm 6 0.05 mm with a depth of 1.5 mm 6 0.10 mm (seeFig. 3 and
31、Fig. X1.1). The contact face has two straight slits at180 opposite to each other with a width of 1 mm with a depthof 1.5 mm 6 0.10 mm. Functional surfaces shall be free fromscratches and any surface damages. The topography of the diskwill be determined by four values:0.200 m 20 s or a coefficient of
32、 friction,f (cut-off value for one-off increase of level): 0.35.8.2.3 Test parameters:Frequency: 50 HzStroke: 1.00 mmTemperature: e.g. +60 C (+80 C, +100 C or +120 C)FIG. 1 SRV Model 5 Test MachineD8227 183Test load: running-in under 50 N for 30 s, then constant loadof 260 N using the standard load
33、step function having a loadramp rate of 15 N s 6 1 N s.8.2.4 Sample rates for result-relevant measurement chan-nels:Coefficient of friction, f: 32 msStroke: 2sTest load: 2sFrequency: 2sTemperature: 2s.NOTE 7For SRV 5 models, it is recommended to do one sampling perperiod (that is, 20 ms) for coeffic
34、ient of friction and stroke.9. Procedure9.1 Using solvent resistant gloves, clean the test pieces anddisk holder by wiping the surfaces with laboratory tissuesoaked with cleaning solvent (single boiling point spirit type2-A according to DIN 51631). (WarningThis mixture isflammable and health hazard.
35、) Repeat wiping until no darkresidue appears on the tissue. Immerse the ball and disk in abeaker of the cleaning solvent under ultrasonic vibration (ifavailable) for 10 min. Dry the disk holder. Dry the test pieceswith a clean tissue, ensuring that no streaking occurs on thesurface.FIG. 2 Test Chamb
36、er Elements of SRV Models 4 and 51 base of the receivingblock7 upper specimen holder2 piezo force measurementelements8 drive rods of the load unit3 supporting surface (headplate) of the receiving block9 test disk4 lower specimen holder 10 test ball5 position of the electricalresistance heating and r
37、esis-tance thermometerFnnormal force (test load)6 oscillation drive rods Fffriction forceFIG. 3 Contact Surface of Upper Specimen with SlitsD8227 1849.2 Ensure that the test load unit is in the release position(refer to operating manual for details).9.3 Carefully place the lower test disk on the tes
38、t areaplatform. Tighten the lower test disk by means of the threescrews at the side of the adapter.9.4 Apply 0.4 mL of lubricating oil with a syringe in thecenter of the lower disk.9.5 Place the upper test disk in the adapter with the levelside facing the adapter and the test surface downwards (Fig.
39、 4).Align the upper test disk as shown in Fig. 5 and make sure, thatthe slit is perpendicular oriented to the sliding direction andtighten it with knurled screws.9.6 Tighten both specimen clamps until resistance to tight-ening just begins. Load unit to 100 N and tighten the specimenclamps to a torqu
40、e of 2.5 Nm. Reduce the load to 50 N forrunning-in.9.7 In the SRV basic software, enter the following testparameters:Frequency = 50 HzStroke = 1.0 mmTemperature = 60 CLoad 50 N for 30 s of running-in, then increase load to 260N using the standard load step functionTest duration = 120 min.10. Report1
41、0.1 During testing, friction coefficient f determined fromtest load Fnand friction load Ffis recorded continuously aswell as actual testing temperature. The evolution of thecoefficient of friction over test time must be stored on datarecords.10.2 Report the following information all parameters usedt
42、o evaluate the lubricant:10.2.1 Temperature, C,10.2.2 Stroke, mm,10.2.3 Frequency, Hz,10.2.4 Relative humidity,10.2.5 Brand name, lab/development code of fluid/oil, typeof base oil, denomination of additive package, kinematicviscosities at 40 C and 100 C,10.2.6 Brass type test disk material (or othe
43、r alloy with orwithout coating),10.2.7 Carburized test disk material (or other alloy with heattreatment with or without thermochemical treatment).10.3 Clean steel disk specimens after testing in an ultra-sound cleaning bath.10.4 Report the coefficient of friction at test end as a floatingaverage ove
44、r 30 s and state in the test report the coefficients offriction at test begin and after each 15 min.11. Precision and Bias11.1 The precision statements were established using testdisks in the same alloys, carburized 20CrMnTi and manganesebrass HMn64-8-5-1.5 according toYS/T 669-2013, homologueto TL-
45、VW084, as used in synchronizers of mechanical shiftinggears. In 2017,11nine co-operators (using eight SRV 4 and oneSRV 5 model) tested twelve commercially available mechani-cal transmission fluids at +60 C, of which 3 samples passedand 2 samples failed to pass bench tests as per Test MethodD5579 and
46、 CEC L-66-99 as well as seven were not benchtested. The precision statements are expressed variable asfunction of the measured coefficient of friction.11.2 PrecisionThe precision of this test method, as deter-mined by statistical examination of the interlaboratory testresults described in 11.1 follo
47、ws:11.2.1 Coefficient of Friction, cof.11.2.1.1 RepeatabilityThe difference between successiveresults obtained by the same operator with the same apparatusunder constant operating conditions on identical test materialwould, in the long run, in the normal and correct operation ofthe test method, exce
48、ed the following value in only one case intwenty.r = 0.001800 cof1.191whereas cof is the coefficient of friction at test end.11.2.1.2 ReproducibilityThe difference between twosingle and independent results obtained by different operatorsworking in different laboratories on the identical test materia
49、l11Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D02-1894. ContactASTM CustomerService at serviceastm.org.FIG. 4 Test Geometry and Contact Position (right) of the Upper Steel Disk Specimen and Lower Brass Disk SpecimenD8227 185would, in the long run, in the normal and correct operation ofthe test method, exceed the following value in only one case intwenty.R = 0.001790 cof1.430whereas cof is the coefficient of frictio
