1、Designation: G65 04 (Reapproved 2010)G65 15Standard 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,
2、 the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers laboratory procedures for determining the resistance of metallic materials to scratch
3、ing abrasion bymeans of the dry sand/rubber wheel test. It is the intent of this test method to produce data that will reproducibly rank materialsin their resistance to scratching abrasion under a specified set of conditions.1.2 Abrasion test results are reported as volume loss in cubic millimetres
4、for the particular test procedure specified. Materialsof higher abrasion resistance will have a lower volume loss.NOTE 1In order to attain uniformity among laboratories, it is the intent of this test method to require that volume loss due to abrasion be reportedonly in the metric system as cubic mil
5、limetres. 1 mm1 mm3 = 6.102 105 in3.1.3 This test method covers five recommended procedures which are appropriate for specific degrees of wear resistance orthicknesses of the test material.1.3.1 Procedure AThis is a relatively severe test which will rank metallic materials on a wide volume loss scal
6、e from low toextreme abrasion resistance. It is particularly useful in ranking 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
7、-abrasive-resistant materials. Procedure B should be used when thevolumeloss values developed by Procedure A exceeds 100 mm3.1.3.3 Procedure CA short-term variation of Procedure A for use on thin coatings.1.3.4 Procedure DThis is a lighter load variation of Procedure A which is particularly useful i
8、n ranking materials oflow-abrasion resistance. It is also used in ranking materials of a specific generic type or materials which would be very close inthe volume loss rates as developed by Procedure A.1.3.5 Procedure EA short-term variation of Procedure B that is useful in the ranking of materials
9、with medium- orlow-abrasion resistance.1.4 This standard does not purport to address the safety concerns, if any, associated with its use. It is the responsibility of theuser of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitatio
10、nsprior to use.2. Referenced Documents2.1 ASTM Standards:2D2240 Test Method for Rubber PropertyDurometer HardnessE11 Specification for Woven Wire Test Sieve Cloth and Test SievesE122 Practice for Calculating Sample Size to Estimate, With Specified Precision, the Average for a Characteristic of a Lot
11、 orProcessE177 Practice for Use of the Terms Precision and Bias in ASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test MethodG40 Terminology Relating to Wear and Erosion2.2 American Foundrymens Society Standards:AFS Foundry Sand Handbook, 7th E
12、dition31 This test method is under the jurisdiction of ASTM Committee G02 on Wear and Erosion and is the direct responsibility of Subcommittee G02.30 on Abrasive Wear.Current edition approved Dec. 1, 2010Nov. 1, 2015. Published December 2010December 2015. Originally approved in 1980. Last previous e
13、dition approved in 20042010as G6504. 04 (2010). DOI: 10.1520/G0065-04R10.10.1520/G0065-15.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summ
14、ary page on the ASTM website.3 Available from American Foundrymens Society, Golf and Wolf Roads, Des Plaines, IL 60016.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit ma
15、y not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harb
16、or Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13. Terminology3.1 Definitions:3.1.1 abrasive wearwear due to hard particles or hard protuberances forced against and moving along a solid surface(Terminology G40).NOTE 2This definition covers several different wear modes or mecha
17、nisms that fall under the abrasive wear category. These modes may degrade asurface by scratching, cutting, deformation, or gouging (1 and 2).44. Summary of Test Method4.1 The dry sand/rubber wheel abrasion test (Fig. 1) involves the abrading of a standard test specimen with a grit of controlledsize
18、and composition. The abrasive is introduced between the test specimen and a rotating wheel with a chlorobutyl rubber tireor rim of a specified hardness. This test specimen is pressed against the rotating wheel at a specified force by means of a leverarm while a controlled flow of grit abrades the te
19、st surface. The rotation of the wheel is such that its contact face moves in thedirection of the sand flow. Note that the pivot axis of the lever arm lies within a plane which is approximately tangent to the rubberwheel surface, and normal to the horizontal diameter along which the load is applied.
20、The test duration and force applied by thelever arm is varied as noted in Procedure A through E. Specimens are weighed before and after the test and the loss in massrecorded. It is necessary to convert the mass loss to volume loss in cubic millimetres, due to the wide differences in the densityof ma
21、terials. 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 depend upon the abrasive particle size, shape, and hardness, the magnitudeof the stress imposed by the particle, and the frequency of contact of the
22、abrasive particle. In this practice these conditions arestandardized to develop a uniform condition of wear which has been referred to as scratching abrasion (1 and 3). The value of thepractice lies in predicting the relative ranking of various materials of construction in an abrasive environment. S
23、ince the practicedoes not attempt to duplicate all of the process conditions (abrasive size, shape, pressure, impact, or corrosive elements), it shouldnot be used to predict the exact resistance of a given material in a specific environment. Its value lies in predicting the rankingof materials in a
24、similar relative order of merit as would occur in an abrasive environment. Volume loss data obtained from testmaterials whose lives are unknown in a specific abrasive environment may, however, be compared with test data obtained froma material whose life is known in the same environment. The compari
25、son will provide a general indication of the worth of theunknown materials if abrasion is the predominant factor causing deterioration of the materials.6. Apparatus and Material56.1 Fig. 2 shows a typical design and Fig. 3 and Fig. 4 are photographs of the test apparatus which may be constructed fro
26、mreadily available materials.Also, see Ref (3). Several elements are of critical importance to ensure uniformity in test results among4 The boldface numbers in parentheses refer to a list of references at the end of this standard.5 Original users of this test method fabricated their own apparatus. M
27、achines are available commercially from several manufacturers of abrasion testing equipment.FIG. 1 Schematic Diagram of Test ApparatusG65 152laboratories. These are the type of rubber used on the wheel, the type of abrasive and the shape, positioning and the size openingof the sand nozzle, and a sui
28、table lever arm system to apply the required force.FIG. 2 Dry Sand/Rubber Wheel Abrasion Test ApparatusFIG. 3 Wheel and Lever ArmG65 1536.2 Rubber WheelThe wheel shown in Fig. 5 shall consist of a steel disk with an outer layer of chlorobutyl rubber moldedto its periphery. Uncured rubber shall be bo
29、nded to the rim and fully cured in a steel mold. The optimum hardness of the curedrubber is Durometer A-60. A range from A58 to 62 is acceptable. At least four hardness readings shall be taken on the rubberapproximately 90 apart around the periphery of the wheel using a Shore A Durometer tester in a
30、ccordance with Test MethodD2240. The gage readings shall be taken after a dwell time of 5 s. The recommended composition of the rubber and a qualifiedmolding source is noted in Table 1. (See 9.9 for preparation and care of the rubber wheel before and after use and see Fig. 2 andFig. 5.)6.3 AbrasiveT
31、he type of abrasive shall be a rounded quartz grain sand as typified by AFS 50/70 Test Sand (Fig. 6).6 Themoisture content shall not exceed 0.5 weight %. Sand that has been subjected to dampness or to continued high relative humiditymay take on moisture, which will affect test results. Moisture cont
32、ent may be determined by measuring the weight loss after heating6 Available from U.S. Silica Co., P.O. Box 577, Ottawa, IL 61350. Sand from other sources was not used in the development of this test method and may give differentresults.FIG. 4 Enclosure FrameFIG. 5 Rubber WheelG65 154a sample to appr
33、oximately 120C (250F) for 1 h minimum. If test sand contains moisture in excess of 0.5 % it shall be dried byheating to 100C (212F) for 1 h minimum and the moisture test repeated. In high-humidity areas sand may be effectively storedin constant temperature and humidity rooms or in an enclosed steel
34、storage bin equipped with a 100-W electric bulb. Weldingelectrode drying ovens, available from welding equipment suppliers are also suitable. Multiple use of the sand may affect testresults and is not recommended. AFS 50/70 Test Sand is controlled to the following size range using U.S. sieves (Speci
35、ficationE11).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 design which was developed to produce an accurate sand flow rate andprop
36、er shape of sand curtain for test procedures. The nozzle may be of any convenient length that will allow for connection to thesand hopper using plastic tubing. In new nozzles, the rate of sand flow is adjusted by grinding the orifice of the nozzle to increasethe width of the opening to develop a san
37、d flow rate of 300 to 400 g/min. During use, the nozzle opening must be positioned asclose to the junction of the test specimen and the rubber wheel as the design will allow. (See Fig. 8.)TABLE 1 Formula for Chlorobutyl RubberANOTE 1Specific gravity of mix: 1.15. Pressure cure: 20 min at 160C(320F).
38、Materials Proportions byWeightChlorobutyl No. HT 10-66 (Enjay Chemical) 100Agerite Staylite-S 1HAF black 60Circolight oil 5Stearic acid 1Zinc oxide 5Ledate 2A The sole source of supply known to the committee at this time is FalexCorporation, 1020 Airpark Dr., Sugar Grove, IL 60554. If you are aware
39、ofalternative suppliers, please provide this information to ASTM Headquarters. Yourcomments will receive careful consideration at a meeting of the responsibletechnical committee, which you may attend.FIG. 6 25X Magnification AFS 50/70 Test Sand Ottawa Silica Co.G65 1556.4.1 Any convenient material o
40、f construction that is available as welded or seamless pipe may be used for the construction ofthe fabricated nozzle. Stainless steel is preferred because of its corrosion resistance and ease of welding. Copper and steel are alsoused successfully.6.4.2 Formed NozzleNozzles formed from tubing may be
41、used only when they duplicate the size and shape (rectangularorifice and taper), and the sand flow characteristics (flow rate and streamlined flow) of the fabricated nozzle. (See Fig. 7 and Fig.9.)6.4.3 Sand FlowThe nozzle must produce a sand flow rate of 300 to 400 g/min (0.66 to 0.88 lb/min).6.4.4
42、 Sand CurtainFig. 9 shows the proper stream-lined flow and the narrow shape of the sand curtain as it exits from the sandnozzle. A turbulent sand flow as depicted in Fig. 10 will tend to produce low and inconsistent test results. It is intended that thesand flows in a streamlined manner and passes b
43、etween the specimen and rubber wheel.6.5 Motor DriveThe wheel is driven by a nominally 0.7-kW (1-hp) dc motor through a 10/1 gear box to ensure that full torqueis delivered during the test. The rate of revolution (200 6 10 rpm) must remain constant under load. Other drives producing 200rpm under loa
44、d are suitable.6.6 Wheel Revolution CounterThe machine shall be equipped with a revolution counter that will monitor the number of wheelrevolutions as specified in the procedure (Section 9). It is recommended that the incremental counter have the ability to shut offthe machine after a preselected nu
45、mber of wheel revolutions or increments up to 12 000 revolutions is attained.6.7 Specimen Holder and Lever ArmThe specimen holder is attached to the lever arm to which weights are added, so that aforce is applied along the horizontal diametral line of the wheel. An appropriate number of weights must
46、 be available to apply theappropriate force (Table 2) between the test specimen and the wheel.The actual weight required should not be calculated, but ratherFIG. 7 Sand NozzleG65 156should be determined by direct measurement by noting the load required to pull the specimen holder away from the wheel
47、. Aconvenient weight system is a can filled with sand (see Fig. 2).6.8 Analytical BalanceThe balance used to measure the loss in mass of the test specimen shall have a sensitivity of 0.001 g.Procedure C requires a sensitivity of 0.0001 g.6.9 Enclosure, Frame, and Abrasive HopperFig. 3 and Fig. 4 are
48、 photographs of a typical test apparatus. The size and shapeof the support elements, enclosure, and hopper may be varied according to the users needs.7. Specimen Preparation and Sampling7.1 MaterialsIt is the intent of this test method to allow for the abrasion testing of any material form, includin
49、g wroughtmetals, castings, forgings, gas or electric weld overlays, plasma spray deposits, powder metals, metallizing, electroplates, cermets,ceramics and so forth. The type of material will, to some extent, determine the overall size of the test specimen.7.2 Typical Specimen, a rectangular shape 25 by 76 mm (1.0 by 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 with the restriction that the length and width be sufficient to show the fulllength of the wear scar as de
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