1、Designation: G 65 04Standard Test Method forMeasuring Abrasion Using the Dry Sand/Rubber WheelApparatus1This standard is issued under the fixed designation G 65; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of last revi
2、sion.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon (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 scratchingabrasion by means
3、 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 volume loss incubic millimetres for the particular test
4、 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 the metric system as cubic millimetres. 1mm3= 6.102 3 1
5、05in3.1.3 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 wide volume loss scale fromlow to extreme abrasion re
6、sistance. 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 medium- and low-abrasive-resistant materials. Pro
7、cedure 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 useful in ranking materials oflow-abrasion resist
8、ance. 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 materials with medium- orlow-abrasion resistance.1.4
9、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 andhealth practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 AST
10、M Standards:2D 2240 Test Method 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 Charac-teristic of a Lot or ProcessE 177 Practice for Use of the
11、 Terms Precision and Bias inASTM Test MethodsG40 Terminology Relating to Wear and Erosion2.2 American Foundrymens Society Standards:AFS Foundry Sand Handbook, 7th Edition33. Terminology3.1 Definition:3.1.1 abrasive wearwear due to hard particles or hardprotuberances forced against and moving along a
12、 solid surface(Terminology G40).NOTE 2This definition covers several different wear modes or mecha-nisms that fall under the abrasive wear category. These modes maydegrade a surface by scratching, cutting, deformation, or gouging (1 and6).41This test method is under the jurisdiction of ASTM Committe
13、e G02 on Wearand Erosion and is the direct responsibility of Subcommittee G02.30 on AbrasiveWear.Current edition approved Nov 1, 2004. Published November 2004. Originallyapproved in 1980. Last previous edition approved in 2000 as G 65 00e1.2For referenced ASTM standards, visit the ASTM website, www.
14、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 American Foundrymens Society, Golf and Wolf Roads, DesPlaines, IL 60016.4The boldface numbers in parenthe
15、ses refer to the list of references at the end ofthis test method.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Summary of Test Method4.1 The dry sand/rubber wheel abrasion test (Fig. 1) in-volves the abrading of a standard test
16、 specimen with a grit ofcontrolled size and composition. The abrasive is introducedbetween the test specimen and a rotating wheel with achlorobutyl rubber tire or rim of a specified hardness. This testspecimen is pressed against the rotating wheel at a specifiedforce by means of a lever arm while a
17、controlled flow of gritabrades the test surface. The rotation of the wheel is such thatits contact face moves in the direction of the sand flow. Notethat the pivot axis of the lever arm lies within a plane which isapproximately tangent to the rubber wheel surface, and normalto the horizontal diamete
18、r along which the load is applied. Thetest duration and force applied by the lever arm is varied asnoted in ProcedureAthrough E. Specimens are weighed beforeand after the test and the loss in mass recorded. It is necessaryto convert the mass loss to volume loss in cubic millimetres,due to the wide d
19、ifferences in the density of materials.Abrasion is reported as volume loss per specified procedure.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 the
20、frequency of contact of the abrasive particle. In this practicethese conditions are standardized to develop a uniform condi-tion of wear which has been referred to as scratching abrasion(1 and 2). The value of the practice lies in predicting therelative ranking of various materials of construction i
21、n anabrasive environment. Since the practice does not attempt toduplicate all of the process conditions (abrasive size, shape,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
22、ranking of mate-rials in a similar relative order of merit as would occur in anabrasive environment. Volume loss data obtained 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 sa
23、meenvironment. The comparison will provide a general indicationof the worth of the unknown materials if abrasion is thepredominant 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 whic
24、h may be constructedfrom readily available materials. Also, see Ref (2). Severalelements are of critical importance to ensure 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 n
25、ozzle, and a suitable leverarm system to apply the required force.6.2 Rubber WheelThe wheel shown in Fig. 5 shall consistof a steel disk with an outer layer of chlorobutyl rubber moldedto its periphery. Uncured rubber shall be bonded to the rim andfully cured in a steel mold. The optimum hardness of
26、 the curedrubber is Durometer A-60. A range from A58 to 62 isacceptable. At least four hardness readings shall be taken onthe rubber approximately 90 apart around the periphery of thewheel using a Shore A Durometer tester in accordance withTest Method D 2240. The gage readings shall be taken after a
27、dwell time of 5 s. The recommended composition of the rubberand a qualified molding source is noted in Table 1. (See 9.9 forpreparation and care of the rubber wheel before and after useand see Fig. 2 and Fig. 5.)6.3 AbrasiveThe type of abrasive shall be a roundedquartz grain sand as typified byAFS 5
28、0/70 Test Sand (Fig. 6).6The moisture content shall not exceed 0.5 weight %. Sand thathas been subjected to dampness or to continued high relativehumidity may take on moisture, which will affect test results.Moisture content may be determined by measuring the weightloss after heating a sample to app
29、roximately 120C (250F) for1 h minimum. If test sand contains 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 st
30、orage bin equipped with a100-W electric bulb. Welding electrode drying ovens, availablefrom welding equipment suppliers are also suitable. Multipleuse 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 (Specificat
31、ion E11).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 passing6.4 Sand NozzleFig. 7 shows the fabricated nozzle designwhich was developed to produce an accurate sand flow rate and5Original
32、 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. Box 577, Ottawa, IL 61350. Sand fromother sources was not used in the development of this test method and may g
33、ivedifferent results.FIG. 1 Schematic Diagram of Test ApparatusG65042proper shape of sand 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 ori
34、fice of the nozzle toFIG. 2 Dry Sand/Rubber Wheel Abrasion Test ApparatusFIG. 3 Wheel and Lever ArmG65043increase the width of the opening to develop a sand flow rateof 300 to 400 g/min. During use, the nozzle opening must bepositioned as close to the junction of the test specimen and therubber whee
35、l 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 the fabricated nozzle. Stainless steel is preferredbecause of its corrosion resistance and ease of welding. Copperand steel are al
36、so 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 characteristics (flow rateand streamlined flow) of the fabricated nozzle. (See Fig. 7 andFig. 9.)6.4.3 Sand FlowThe nozzle must
37、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 exits fromthe sand nozzle. A turbulent sand flow as depicted in Fig. 10will tend to produce low and inconsistent test results. I
38、t isintended that the sand flows in a streamlined manner andpasses between the specimen and rubber wheel.FIG. 4 Enclosure FrameFIG. 5 Rubber WheelG650446.5 Motor DriveThe wheel is driven by a nominally0.7-kW (1-hp) dc motor through a 10/1 gear box to ensure thatfull torque is delivered during the te
39、st. 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 will monitor thenumber of wheel revolutions as specified in the procedure(Section 9)
40、. 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 ArmThe specimen holderis attached to the lever arm to which weights are added, so th
41、ata force is applied along the horizontal diametral line of thewheel. An appropriate number of weights must be available toapply the appropriate force (Table 2) between the test specimenand the wheel. The actual weight required should not becalculated, but rather should be determined by direct measu
42、re-ment by noting the load required to pull the specimen holderaway from the wheel. A convenient weight system is a canfilled with sand (see Fig. 2).6.8 Analytical BalanceThe balance used to measure theloss in mass of the test specimen shall have a sensitivity of0.001 g. Procedure C requires a sensi
43、tivity of 0.0001 g.6.9 Enclosure, Frame, and Abrasive HopperFig. 3 andFig. 4 are photographs of a typical test apparatus. The size andshape of the support elements, enclosure, and hopper may bevaried according to the users needs.7. Specimen Preparation and Sampling7.1 MaterialsIt is the intent of th
44、is test method to allowfor the abrasion testing of any material form, includingwrought metals, castings, forgings, gas or electric weld over-lays, plasma spray deposits, powder metals, metallizing, elec-troplates, cermets, ceramics and so forth. The type of materialwill, to some extent, determine th
45、e overall size of the testspecimen.7.2 Typical Specimen, a rectangular shape 25 by 76 mm (1.0by 3.0 in.) and between 3.2 and 12.7 mm (0.12 and 0.50 in.)thick. The size may be varied according to the users need withthe restriction that the length and width be sufficient to showthe full length of the
46、wear scar as developed by the test. Thetest surface should be flat within 0.125 mm (0.005 in.)maximum.7.3 Wrought, Cast, and Forged MetalSpecimens may bemachined to size directly from the raw material.7.4 Electric or Gas Weld Deposits are applied to one flatsurface of the test piece. Double-weld pas
47、ses are recommendedto prevent weld dilution by the base metal. The heat of weldingmay distort the test specimen. When this occurs, the specimenmay be mechanically straightened or ground, or both. In orderto develop a suitable wear scar, the surface to be abraded mustbe ground flat to produce a smoot
48、h, level surface at least 63.4mm (2.50 in.) long and 19.1 mm (0.75 in.) for the test. (See7.5.) Note that the welder technique, heat input of welds, andthe flame adjustment of gas welds will have an effect on theabrasion resistance of a weld deposit.7.5 FinishTest specimens should be smooth, flat, a
49、nd 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. Typical suitablesurfaces are mill-rolled surfaces such as are present on cold-rolled steel, electroplated and similar deposits, ground sur-faces, and finely machined or milled surfaces.Aground surfacefinish of approximately 0.8 m (32 in.) or less is acceptable.The type of surface or surface preparation shall be stated in thedata sheet.8. Test Parameters8.1 Table 2 indica
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