1、Designation: G105 16Standard Test Method forConducting Wet Sand/Rubber Wheel Abrasion Tests1This standard is issued under the fixed designation G105; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A numb
2、er 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 covers laboratory procedures for de-termining the resistance of metallic materials to scratchingabrasion by means of the w
3、et sand/rubber wheel test. It is theintent of this procedure to provide data that will reproduciblyrank materials in their resistance to scratching abrasion undera specified set of conditions.1.2 Abrasion test results are reported as volume loss incubic millimetres. Materials of higher abrasion resi
4、stance willhave a lower volume loss.1.3 The values stated in SI units are to be regarded asstandard. 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 o
5、f 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 ASTM Standards:2D2000 Classification System for Rubber Products in Auto-motive ApplicationsD2240 Test Method for Rubber PropertyDur
6、ometer Hard-nessE11 Specification for Woven Wire Test Sieve Cloth and TestSievesE122 Practice for Calculating Sample Size to Estimate, WithSpecified Precision, the Average for a Characteristic of aLot or ProcessE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsG40 Terminology
7、Relating to Wear and Erosion2.2 SAE Standard:3SAE J200 Classification System for Rubber Materials3. Terminology3.1 Definitions:3.1.1 abrasive wearwear due to hard particles or hardprotuberances forced against and moving along a solid surface.3.1.1.1 DiscussionThis definition covers several different
8、wear modes or mechanisms that fall under the abrasive wearcategory. These modes may degrade a surface by scratching,cutting, deformation, or gouging (1 and 2).4G404. Summary of Test Method4.1 The wet sand/rubber wheel abrasion test (Fig. 1) in-volves the abrading of a standard test specimen with a s
9、lurrycontaining grit of controlled size and composition. The abra-sive is introduced between the test specimen and a rotatingwheel with a neoprene rubber tire or rim of a specifiedhardness. The test specimen is pressed against the rotatingwheel at a specified force by means of a lever arm while theg
10、rit abrades the test surface. The rotation of the wheel is suchthat stirring paddles on both sides agitate the abrasive slurrythrough which it passes to provide grit particles to be carriedacross the contact face in the direction of wheel rotation.4.2 Three wheels are required with nominal Shore ADu
11、rometer hardnesses of 50, 60, and 70, with a hardnesstolerance of 62.0.Arun-in is conducted with the 50 Durometerwheel, followed by the test with 50, 60, and 70 Durometerwheels in order of increasing hardness. Specimens are weighedbefore and after each run and the loss in mass recorded. Thelogarithm
12、s of mass loss are plotted as a function of measuredrubber wheel hardness and a test value is determined from aleast square line as the mass loss at 60.0 Durometer. It isnecessary to convert the mass loss to volume loss, due to widedifferences in density of materials, in order to obtain a rankingof
13、materials. Abrasion is then reported as volume loss in cubicmillimetres.1This test method is under the jurisdiction of ASTM Committee G02 on Wearand Erosion and is the direct responsibility of Subcommittee G02.30 on AbrasiveWear.Current edition approved June 1, 2016. Published June 2016. Originallya
14、pproved in 1989. Last previous edition approved in 2007 as G105 02 (2007)which was withdrawn January 2016 and reinstated in June 2016. DOI: 10.1520/G0105-16.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of AS
15、TMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from Society of Automotive Engineers (SAE), 400 CommonwealthDr., Warrendale, PA 15096-0001.4The boldface numbers in parentheses refer to the list of references at the end ofthis standard.Copyri
16、ght ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15. Significance and Use (1-7)5.1 The severity of abrasive wear in any system will dependupon the abrasive particle size, shape and hardness, themagnitude of the stress imposed by the particle,
17、 and thefrequency of contact of the abrasive particle. In this testmethod these conditions are standardized to develop a uniformcondition of wear which has been referred to as scratchingabrasion (1 and 2). Since the test method does not attempt toduplicate all of the process conditions (abrasive siz
18、e, shape,pressure, impact or corrosive elements), it should not be usedto predict the exact resistance of a given material in a specificenvironment. The value of the test method lies in predicting theranking of materials in a similar relative order of merit aswould occur in an abrasive environment.
19、Volume loss dataobtained from test materials whose lives are unknown in aspecific abrasive environment may, however, be comparedwith test data obtained from a material whose life is known inthe same environment. The comparison will provide a generalindication of the worth of the unknown materials if
20、 abrasion isthe predominant factor causing deterioration of the materials.6. Apparatus56.1 Fig. 2 shows a typical design and Figs. 3 and 4 arephotographs of a test apparatus. (See Ref (4).) Several elementsare of critical importance to ensure uniformity in test resultsamong laboratories. These are t
21、he type of rubber used on thewheel, the type of abrasive and its shape, uniformity of the testapparatus, a suitable lever arm system to apply the requiredforce (see Note 1) and test material uniformity.NOTE 1An apparatus design that is commercially available is depictedboth schematically and in phot
22、ographs in Figs. 1-4. Although it has beenused by several laboratories (including those running interlaboratory tests)to obtain wear data, it incorporates what may be considered a design flaw.The location of the pivot point between the lever arm and the specimenholder is not directly in line with th
23、e test specimen surface. Unless thetangent to the wheel at the center point of the area or line of contactbetween the wheel and specimen also passes through the pivot axis of theloading arm, a variable, undefined, and uncompensated torque about thepivot will be caused by the frictional drag of the w
24、heel against thespecimen. Therefore, the true loading of specimen against the wheelcannot be known.6.1.1 DiscussionThe location of the pivot point betweenthe lever arm and the specimen holder must be directly in linewith the test specimen surface. Unless the tangent to the wheelat the center point o
25、f the area or line of contact between thewheel and specimen also passes through the pivot axis of theloading arm, a variable, undefined, and uncompensated torqueabout the pivot will be caused by the frictional drag of thewheel against the specimen. Therefore, the true loading ofspecimen against the
26、wheel cannot be known.6.2 Rubber WheelEach wheel shall consist of a steel diskwith an outer layer of neoprene rubber molded to its periphery.The rubber is bonded to the rim and cured in a suitable steelmold. Wheels are nominally 178 mm (7 in.) diameter by 13mm (12 in.) wide (see Fig. 2). The rubber
27、will conform toClassification D2000 (SAE J200).5Present users of this test method may have constructed their own equipment.Rubber wheel abrasion testing equipment is commercially available. Rubber wheelsor remolded rims on wheel hubs can be obtained through the manufacturer(s).FIG. 1 Schematic Diagr
28、am of the Wear Test ApparatusFIG. 2 Rubber WheelFIG. 3 Test Apparatus with Slurry Chamber Cover RemovedG105 1626.2.1 The 50 Durometer wheel will be in accordance with2BC515K11Z1Z2Z3Z4, where:Z1ElastomerNeoprene GW,Z2Type A Durometer hardness 50 6 2,Z3Not less than 50 % rubber hydrocarbon content, an
29、dZ4Medium thermal black reinforcement.6.2.2 The 60 Durometer wheel will be in accordance with2BC615K11Z1Z2Z3Z4, where:Z1, Z3, and Z4 are the same as for 6.2.1, andZ2Type A Durometer hardness 60 6 2.6.2.3 The 70 Durometer wheel will be in accordance with2BC715K11Z1Z2Z3Z4, where:Z1, Z3, and Z4 are the
30、 same as for 6.2.1, andZ2Type A Durometer hardness 70 6 2.6.2.4 The compounds suggested for the 50, 60, and 70Durometer rubber wheels are as follows:IngredientContent (pph)50 60 70Neoprene GW 100 100 100MagnesiaA222Zinc OxideB10 10 10Octamine 2 2 2Stearic Acid 0.5 0.5 0.5SRF Carbon BlackC20 37 63AST
31、M #3 Oil 14 10 10AMaglite D (Merck)BKadox 15 (New Jersey Zinc)CASTM Grade N7626.2.5 Wheels are molded under pressure. Cure times of 40to 60 min at 153C (307F) are used to minimize “heat-to-heat variations.6.3 Motor DriveThe wheel is driven by a 0.75-kw (1-hp)electric motor and suitable gear box to e
32、nsure that full torqueis delivered during the test. The rate of revolution (245 6 5rpm) must remain constant under load. Other drives producing245 rpm under load are suitable.6.4 Wheel Revolution CounterThe machine shall beequipped with a revolution counter that will monitor thenumber of wheel revol
33、utions as specified in the procedure. It isrecommended that the incremental counter have the ability toshut off the machine after a preselected number of wheelrevolutions or increments up to 5000 revolutions is attained.6.5 Specimen Holder and Lever ArmThe specimen holderis attached to the lever arm
34、 to which weights are added so thata force is applied along the horizontal diametral line of thewheel. An appropriate weight must be used to apply a force of222 N (50 lbf) between the test specimen positioned in thespecimen holder and the wheel. The weight has a mass ofapproximately 9.5 kg (21 lb) a
35、nd must be adjusted so that theforce exerted by the rubber wheel on the specimen with therubber wheel at rest has a value of 222.4 6 3.6 N (50.0 6 0.8lbf). This force may be determined by calculation of themoments acting around the pivot point for the lever arm or bydirect measurement, for example,
36、by noting the load requiredto pull the specimen holder away from the wheel, or with aproving ring.6.6 Analytical BalanceThe balance used to measure theloss in mass of the test specimen shall have a sensitivity of0.0001 g. A 150 g capacity balance is recommended toaccommodate thicker or high density
37、specimens.7. Reagents and Materials7.1 Abrasive SlurryThe abrasive slurry used in the testshall consist of a mixture of 0.940 kg of deionized water and1.500 kg of a rounded grain quartz sand as typified by AFS50/70 Test Sand (50/ +70 mesh, or 230 +270 m) furnishedby the qualified source.67.2 AFS 50/
38、70 test sand is controlled by the qualified sourceto the following size range using U.S. Sieves (SpecificationE11).6The sole source of supply of the apparatus known to the committee at this timeis Ottawa Silica Co., P.O. Box 577, Ottawa, IL61350. If you are aware of alternativesuppliers, please prov
39、ide this information to ASTM International Headquarters.Your comments will receive careful consideration at a meeting of the responsibletechnical committee,1which you may attend.FIG. 4 Test Apparatus in OperationG105 163U.S. Sieve Size Sieve Opening %Retained on Sieve40 425 m (0.0165 in.) None50 300
40、 m (0.0117 in.) 5 max70 212 m (0.0083 in.) 95 min100 150 m (0.0059 in.) None Passing7.2.1 Multiple use of the sand may affect the test compari-sons.8. Sampling, Test Specimen, and Test Units8.1 Test UnitUse any metallic material form for abrasiontesting by this method. This includes wrought metals,
41、castings,forgings, weld overlays, thermal spray deposits, powdermetals, electroplates, cermets, etc.8.2 Test SpecimenThe test specimens are rectangular inshape, 25.4 6 0.8 mm (1.00 6 0.03 in.) wide by 57.2 6 0.8mm (2.25 6 0.03 in.) long by 6.4 to 15.9 mm (0.25 to 0.625in.) thick. The test surface sh
42、ould be flat within 0.125 mm(0.005 in.) maximum.8.2.1 For specimens less than 9.5 mm thick (0.375 in.), usea shim in the specimen holder to bring the specimen to a heightof 9.5 mm.8.3 Wrought and Cast MetalSpecimens may be machinedto size directly from raw material.8.4 Weld deposits are applied to o
43、ne flat surface of the testpiece. Double-weld passes are recommended to prevent welddilution by the base metal. Note that welder technique, heatinput of welds, and the flame adjustment of gas welds will havean effect on the abrasion resistance of the weld deposit. Welddeposits should be made on a th
44、ick enough substrate, 12.7 mm(0.5 in.) minimum suggested, to prevent distortion. If distortionoccurs, the specimen may be mechanically straightened orground or both.8.4.1 In order to develop a suitable wear scar, the surface tobe abraded must be ground flat to produce a smooth, levelsurface. A test
45、surface without square (90) edges, having alevel surface at least 50.8 mm (2.00 in.) long and 19.1 mm(0.75 in.) wide, is acceptable if it can be positioned to show thefull length and width of the wear scar developed by the test.8.5 CoatingsThis test may be unsuitable for somecoatings, depending on t
46、heir thickness, wear resistance, bondto the substrate, and other factors. The criterion for acceptabil-ity is the ability of the coating to resist penetration to itssubstrate during conduct of the test. Modified procedures forcoatings may be developed based on this procedure.8.6 FinishTest specimens
47、 should be smooth, flat and freeof scale. Surface defects such as porosity and roughness maybias the test results, and such specimens should be avoidedunless the surface itself is under investigation. Exceptingcoatings, the last 0.3 mm (0.01 in.) of stock on the test surface(or surfaces in cases whe
48、re both major surfaces are to be tested)should be carefully wet ground to a surface finish of about 0.5to 0.75 m (20 to 30 in.) arithmetic average as measuredacross the direction of grinding. The direction of the grindingshould be parallel to the longest axis of the specimen. Thefinished surface sho
49、uld be free of artifacts of specimen heattreatment or preparation such as unintentional carburization ordecarburization, heat checks, porosity, slag inclusions, gasvoids, etc.8.6.1 Thin coatings may be tested in the as-coated conditionsince surface grinding, especially of those less than about 0.3mm (0.01 in.) thick, can penetrate the coating or cause it to beso thin that it will not survive that test without penetration. Thefinish of the substrate test surface prior to coating should besuch to minimize irregularities in the coated surface. G
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