1、Designation: G65 161Standard Test Method forMeasuring Abrasion Using the Dry Sand/Rubber WheelApparatus1This standard is issued under the fixed designation G65; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of last revis
2、ion.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon () indicates an editorial change since the last revision or reapproval.1NOTEEditorially corrected Table X1.3 in November 2017.1. Scope1.1 This test method covers laboratory procedures for de-termining the resistance
3、 of metallic materials to scratchingabrasion by means of the dry sand/rubber wheel test. It is theintent of this test method to produce data that will reproduciblyrank materials in their resistance to scratching abrasion undera specified set of conditions.1.2 Abrasion test results are reported as vo
4、lume loss incubic millimetres for the particular test procedure specified.Materials of higher abrasion resistance will have a lowervolume loss.NOTE 1In order to attain uniformity among laboratories, it is theintent of this test method to require that volume loss due to abrasion bereported only in th
5、e metric system as cubic millimetres.1mm3= 6.102 105in3.1.3 This test method covers five recommended procedureswhich are appropriate for specific degrees of wear resistance orthicknesses of the test material.1.3.1 Procedure AThis is a relatively severe test whichwill rank metallic materials on a wid
6、e volume loss scale fromlow to extreme abrasion resistance. It is particularly useful inranking materials of medium to extreme abrasion resistance.1.3.2 Procedure BA short-term variation of Procedure A.It may be used for highly abrasive resistant materials but isparticularly useful in the ranking of
7、 medium- and low-abrasive-resistant materials. Procedure B should be used whenthe volumeloss values developed by ProcedureAexceeds 100mm3.1.3.3 Procedure CA short-term variation of Procedure Afor use on thin coatings.1.3.4 Procedure DThis is a lighter load variation ofProcedureAwhich is particularly
8、 useful in ranking materials oflow-abrasion resistance. It is also used in ranking materials ofa specific generic type or materials which would be very closein the volume loss rates as developed by Procedure A.1.3.5 Procedure EA short-term variation of Procedure Bthat is useful in the ranking of mat
9、erials with medium- orlow-abrasion resistance.1.4 This standard does not purport to address the safetyconcerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety,health, and environmental practices and determine the appli-cability o
10、f regulatory limitations prior to use.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World T
11、rade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D2000 Classification System for Rubber Products in Auto-motive ApplicationsD2240 Test Method for Rubber PropertyDurometer Hard-nessE11 Specification for Woven Wire Test Sieve Cloth and TestSievesE
12、122 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 MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodG
13、40 Terminology Relating to Wear and ErosionG105 Test Method for Conducting Wet Sand/Rubber WheelAbrasion Tests1This 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 March 1,
14、 2016. Published March 2016. Originallyapproved in 1980. Last previous edition approved in 2015 as G65 15. DOI:10.1520/G0065-16E01.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume informa
15、tion, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization
16、 established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.12.2 American Foundrymens Society Standards:AFS Foundry Sand Handbook, 7th Edition33. Terminology3.1
17、 Definitions:3.1.1 abrasive wearwear due to hard particles or hardprotuberances forced against and moving along a solid surface(Terminology G40).NOTE 2This definition covers several different wear modes ormechanisms that fall under the abrasive wear category. These modes maydegrade a surface by scra
18、tching, cutting, deformation, or gouging (1 and2).44. Summary of Test Method4.1 The dry sand/rubber wheel abrasion test (Fig. 1) in-volves the abrading of a standard test specimen with a grit ofcontrolled size and composition. The abrasive is introducedbetween the test specimen and a rotating wheel
19、with achlorobutyl or neoprene rubber rim of a specified hardness.This test specimen is pressed against the rotating wheel at aspecified force by means of a lever arm while a controlled flowof grit abrades the test surface. The rotation of the wheel issuch that its contact face moves in the direction
20、 of the sandflow. Note that the pivot axis of the lever arm lies within aplane that is approximately tangent to the rubber wheel surface,and normal to the horizontal diameter along which the load isapplied. The test duration and force applied by the lever arm isvaried as noted in Procedure A through
21、 E. Specimens areweighed before and after the test and the loss in mass recorded.It is necessary to convert the mass loss to volume loss in cubicmillimetres, due to the wide differences in the density ofmaterials. Abrasion is reported as volume loss per specifiedprocedure.5. Significance and Use (1-
22、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 thefrequency of contact of the abrasive particle. In this practicethese conditions are standardized to develop a uniform condi-ti
23、on of wear which has been referred to as scratching abrasion(1 and 3). The value of the practice lies in predicting therelative ranking of various materials of construction in anabrasive environment. Since the practice does not attempt toduplicate all of the process conditions (abrasive size, shape,
24、pressure, impact, or corrosive elements), it should not be usedto predict the exact resistance of a given material in a specificenvironment. Its value lies in predicting the ranking of mate-rials in a similar relative order of merit as would occur in anabrasive environment. Volume loss data obtained
25、 from testmaterials whose lives are unknown in a specific abrasiveenvironment may, however, be compared with test data ob-tained from a material whose life is known in the sameenvironment. The comparison will provide a general indicationof the worth of the unknown materials if abrasion is thepredomi
26、nant factor causing deterioration of the materials.6. Apparatus and Material56.1 Fig. 2 shows a typical design and Fig. 3 and Fig. 4 arephotographs of the test apparatus which may be constructedfrom readily available materials. Also, see Ref (3). Severalelements are of critical importance to ensure
27、uniformity in testresults among laboratories. These are the type of rubber usedon the wheel, the type of abrasive and the shape, positioningand the size opening of the sand nozzle, and a suitable leverarm system to apply the required force.6.2 Rubber WheelThe wheel shown in Fig. 5 shall consistof a
28、steel disk with an outer layer of chlorobutyl or neoprenerubber molded to its periphery. Uncured rubber shall be bondedto the rim and fully cured in a steel mold. The optimumhardness of the cured rubber is Durometer A-60. A range fromA58 to 62 is acceptable. At least four hardness readings shallbe t
29、aken on the rubber approximately 90 apart around theperiphery of the wheel using a Shore A Durometer tester inaccordance with Test Method D2240. The gage readings shallbe taken after a dwell time of 5 s. The recommendedcomposition of the rubber and a qualified molding source isnoted in Table 1 and T
30、able 2. (See 9.9 for preparation and careof the rubber wheel before and after use and see Fig. 2 and Fig.5.)6.3 AbrasiveThe type of abrasive shall be a roundedquartz grain sand as typified byAFS 50/70 Test Sand (Fig. 6).63Available from American Foundrymens Society, Golf and Wolf Roads, DesPlaines,
31、IL 60016.4The boldface numbers in parentheses refer to a list of references at the end ofthis standard.5Original users of this test method fabricated their own apparatus. Machines areavailable commercially from several manufacturers of abrasion testing equipment.6Available from U.S. Silica Co., P.O.
32、 Box 577, Ottawa, IL 61350. Sand fromother sources was not used in the development of this test method and may givedifferent results.FIG. 1 Schematic Diagram of Test ApparatusG651612The moisture content shall not exceed 0.5 weight %. Sand thathas been subjected to dampness or to continued high relat
33、ivehumidity may take on moisture, which will affect test results.Moisture content may be determined by measuring the weightFIG. 2 Dry Sand/Rubber Wheel Abrasion Test ApparatusFIG. 3 Wheel and Lever ArmG651613loss after heating a sample to approximately 120C (250F) for1 h minimum. If test sand contai
34、ns moisture in excess of 0.5 %it shall be dried by heating to 100C (212F) for 1 h minimumand the moisture test repeated. In high-humidity areas sandmay be effectively stored in constant temperature and humidityrooms or in an enclosed steel storage bin equipped with a100-W electric bulb. Welding elec
35、trode drying ovens, availablefrom welding equipment suppliers are also suitable. MultipleFIG. 4 Enclosure FrameFIG. 5 Rubber WheelG651614use of the sand may affect test results and is not recommended.AFS 50/70 Test Sand is controlled to the following size rangeusing U.S. sieves (Specification E11).U
36、.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 passing6.4 Sand NozzleFig. 7 shows the fabricated nozzle designwhich was developed to produce an accurate sand flow rate andproper shape of san
37、d curtain for test procedures. The nozzlemay be of any convenient length that will allow for connectionto the sand hopper using plastic tubing. In new nozzles, the rateof sand flow is adjusted by grinding the orifice of the nozzle toincrease the width of the opening to develop a sand flow rateof 300
38、 to 400 g/min. During use, the nozzle opening must bepositioned as close to the junction of the test specimen and therubber wheel as the design will allow. (See Fig. 8.)6.4.1 Any convenient material of construction that is avail-able as welded or seamless pipe may be used for the construc-tion of th
39、e fabricated nozzle. Stainless steel is preferredbecause of its corrosion resistance and ease of welding. Copperand steel are also used successfully.6.4.2 Formed NozzleNozzles formed from tubing may beused only when they duplicate the size and shape (rectangularorifice and taper), and the sand flow
40、characteristics (flow rateand streamlined flow) of the fabricated nozzle. (See Fig. 7 andFig. 9.)6.4.3 Sand FlowThe nozzle must produce a sand flow rateof 300 to 400 g/min (0.66 to 0.88 lb/min).6.4.4 Sand CurtainFig. 9 shows the proper stream-linedflow and the narrow shape of the sand curtain as it
41、exits fromthe sand nozzle. A turbulent sand flow as depicted in Fig. 10will tend to produce low and inconsistent test results. It isintended that the sand flows in a streamlined manner andpasses between the specimen and rubber wheel.6.5 Motor DriveThe wheel is driven by a nominally0.7-kW (1-hp) dc m
42、otor through a 10/1 gear box to ensure thatfull torque is delivered during the test. The rate of revolution(200 6 10 rpm) must remain constant under load. Other drivesproducing 200 rpm under load are suitable.6.6 Wheel Revolution CounterThe machine shall beequipped with a revolution counter that wil
43、l monitor thenumber of wheel revolutions as specified in the procedure(Section 9). It is recommended that the incremental counterhave the ability to shut off the machine after a preselectednumber of wheel revolutions or increments up to 12 000revolutions is attained.6.7 Specimen Holder and Lever Arm
44、The specimen holderis attached to the lever arm to which weights are added, so thatTABLE 1 A Formula for Chlorobutyl RubberANOTE 1Specific gravity of mix: 1.15. Pressure cure: 20 min at 160C(320F).MaterialsProportions byWeightChlorobutyl No. HT 10-66 (Enjay Chemical) 100Agerite Staylite-S 1HAF black
45、 60Circolight oil 5Stearic acid 1Zinc oxide 5Ledate 2AThe sole source of supply known to the committee at this time is FalexCorporation, 1020 Airpark Dr., Sugar Grove, IL 60554. If you are aware ofalternative suppliers, please provide this information to ASTM Headquarters. Yourcomments will receive
46、careful consideration at a meeting of the responsibletechnical committee, which you may attend.TABLE 2 Formula for Neoprene RubberANOTE 1The rubber will conform to Classification D2000.NOTE 2The 60 Durometer wheel will be in accordance with2BC615K11Z1Z2Z3Z4, where Z1ElastomerNeoprene GW, Z2Type ADur
47、ometer hardness 60 2, Z3Not less than 50 % rubber hydrocarboncontent, and Z4Medium thermal black reinforcement.NOTE 3The wheels are molded under pressure. Cure tiems of 40 to 60min at 153C (307F) are used to minimize “heat-to-heat” variations.Materials Proportions by WeightNeoprene GW 100MagnesiaB2Z
48、inc OxideC10Octamine 2Stearic Acid 0.5SRF Carbon BlackD37ASTM #3 Oil 10AThe sole source of supply known to the committee at this time is FalexCorporation, 1020 Airpark Dr., Sugar Grove, IL 60554. If you are aware ofalternative suppliers, please provide this information to ASTM Headquarters. Yourcomm
49、ents will receive careful consideration at a meeting of the responsibletechnical committee, which you may attend.BMaglite D (Merck)CKadox 16 (Ner Jersey Zinc)DASTM Grade N762FIG. 6 25X Magnification AFS 50/70 Test Sand Ottawa Silica Co.G651615a force is applied along the horizontal diametral line of thewheel. An appropriate number of weights must be available toapply the appropriate force (Table 3) between the test specimenand the wheel. The actual weight required should not becalculated, but rather should be determined by dir
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