1、Designation: G 105 02 (Reapproved 2007)Standard Test Method forConducting Wet Sand/Rubber Wheel Abrasion Tests1This standard is issued under the fixed designation G 105; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of l
2、ast revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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 scratchingabras
3、ion by means of the wet 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 millimeters. Materials of
4、 higher abrasion resistance willhave a lower volume loss.1.3 The values stated in SI units are to 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 theres
5、ponsibility of the user of 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:2D 2000 Classification System for Rubber Products in Auto-motive ApplicationsD 2240 Test Me
6、thod for Rubber PropertyDurometerHardnessE11 Specification for Wire Cloth and Sieves for TestingPurposesE 122 Practice for Calculating Sample Size to Estimate,With a Specified Tolerable Error, the Average for aCharacteristic of a Lot or ProcessE 177 Practice for Use of the Terms Precision and Bias i
7、nASTM Test MethodsG40 Terminology Relating to Wear and Erosion2.2 SAE Standard:3SAE J200 Classification System for Rubber Materials3. Terminology3.1 Definitions:3.2 abrasive wearwear due to hard particles or hardprotuberances forced against and moving along a solid surface.3.2.1 DiscussionThis defin
8、ition covers several differentwear 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 s
9、tandard test specimen with a slurrycontaining 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 m
10、eans of a lever arm while thegrit 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 r
11、equired with nominal Shore ADurometer 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
12、in mass recorded. Thelogarithms 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, i
13、n order to obtain a rankingof materials. Abrasion is then reported as volume loss in cubicmillimetres.5. 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, and t
14、he1This 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 July 1, 2007. Published September 2007. Originallyapproved in 1989. Last previous edition approved in 2002 as G 1050
15、2.2For 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.3Available from Society of Automotive Engineers (SAE), 400
16、CommonwealthDr., Warrendale, PA 15096-0001.4The boldface numbers in parentheses refer to the list of references at the end ofthis standard.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.frequency of contact of the abrasive particle.
17、 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 size, shape,pressure, impact or corrosive elements), it s
18、hould 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. Volume loss dataobtained from test materials whose liv
19、es 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 abrasion isthe predominant factor causing deteriorati
20、on 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 the type of rubber used on thewheel, the type of abrasi
21、ve 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 de-picted both schematically and in photographs in Figs. 1-4.Although it hasbeen used by sev
22、eral laboratories (including those running interlaboratorytests) to obtain wear data, it incorporates what may be considered a designflaw. The location of the pivot point between the lever arm and thespecimen holder is not directly in line with the test specimen surface.Unless the tangent to the whe
23、el at the center point of the area or line ofcontact between the wheel and specimen also passes through the pivot axisof the loading arm, a variable, undefined, and uncompensated torque aboutthe pivot will be caused by the frictional drag of the wheel against thespecimen. Therefore, the true loading
24、 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 of the area or line of contact between thewheel and sp
25、ecimen 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 wheel cannot be known.6.2 Rubber WheelEach wheel shal
26、l 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 will conform toClassification D 2000 (SAE J200).6.2.1
27、 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, and5Present users of this test method may have constructed their own equipment.Rubber wheel abrasion testing equipment
28、 is commercially available. Rubber wheelsor remolded rims on wheel hubs can be obtained through the manufacturer(s).FIG. 1 Schematic Diagram of the Wear Test ApparatusFIG. 2 Rubber WheelFIG. 3 Test Apparatus with Slurry Chamber Cover RemovedG 105 02 (2007)2Z4Medium thermal black reinforcement.6.2.2
29、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 same as for 6.2.1, andZ2Type A Durometer ha
30、rdness 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 63ASTM #3 Oil 14 10 10AMaglite D (Merck)BKadox 15
31、 (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 ensure that full torqueis delivered during th
32、e 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 revolutions as specified in the procedure. It isr
33、ecommended 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 to which weights are added so thata force i
34、s 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) and must be adjusted so that theforce exerted
35、 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, by noting the load requiredto pull the speci
36、men 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. A150 g capacity balance is recommended to accom-modate thicker or high density specimens.7. Reagents and Materials7.1 Abra
37、sive 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 50/70 test sand is controlled by the qualifie
38、d sourceto the following size range using U.S. Sieves (SpecificationE11).U.S. Sieve Size Sieve Opening %Retained on Sieve40 425 m (0.0165 in.) None50 300 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
39、.8. Sampling, Test Specimen, and Test Units8.1 Test UnitUse any metallic material form for abrasiontesting by this method. This includes wrought metals, castings,forgings, weld overlays, thermal spray deposits, powder met-als, electroplates, cermets, etc.8.2 Test SpecimenThe test specimens are recta
40、ngular inshape, 25.4 6 0.8 mm (1.00 6 0.03 in.) wide by 57.2 6 0.8mm (2.256 0.03 in.) long by 6.4 to 15.9 mm (0.25 to 0.625 in.)thick. The test surface should be flat within 0.125 mm (0.005in.) maximum.8.2.1 For specimens less than 9.5 mm thick (0.375 in.), usea shim in the specimen holder to bring
41、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 one flat surface of the testpiece. Double-weld passes are recommended to prevent welddilution by the base metal. Note that welder technique, heatin
42、put of welds, and the flame adjustment of gas welds will have6The 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 provide this information to ASTM International Headquarter
43、s.Your comments will receive careful consideration at a meeting of the responsibletechnical committee,1which you may attend.FIG. 4 Test Apparatus in OperationG 105 02 (2007)3an effect on the abrasion resistance of the weld deposit. Welddeposits should be made on a thick enough substrate, 12.7 mm(0.5
44、 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 surface without square (90) edges
45、, 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 some coat-ings, depending on their thickness, wear resistance
46、, bond to thesubstrate, and other factors. The criterion for acceptability isthe ability of the coating to resist penetration to its substrateduring conduct of the test. Modified procedures for coatingsmay be developed based on this procedure.8.6 FinishTest specimens should be smooth, flat and freeo
47、f 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 where both major surfaces are to be
48、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 should be free of artifacts of speci
49、men 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. Grindingof this surface as directed i
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