1、Designation: G65 15G65 16Standard 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
2、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 scratching abrasion bymea
3、ns 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 for the particular
4、 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 millimetres. 1 mm3 =
5、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 scale from low toextreme a
6、brasion 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-abrasive-resistant ma
7、terials. 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 in ranking materials of
8、low-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 with medium- orlow-abr
9、asion 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 limitationsprior to use.2. Refe
10、renced Documents2.1 ASTM Standards:2D2000 Classification System for Rubber Products in Automotive ApplicationsD2240 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
11、Precision, the Average for a Characteristic of a Lot 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 ErosionG105 Test Method for Co
12、nducting Wet Sand/Rubber Wheel Abrasion Tests (Withdrawn 2016)31 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 Nov. 1, 2015March 1, 2016. Published December 2015Ma
13、rch 2016. Originally approved in 1980. Last previous edition approved in 20102015as G65G65 15.04 (2010). DOI: 10.1520/G0065-15.10.1520/G0065-16.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvo
14、lume information, refer to the standards Document Summary page on the ASTM website.3 The last approved version of this historical standard is referenced on www.astm.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes ha
15、ve been made to the previous version. Becauseit may 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 do
16、cument.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States12.2 American Foundrymens Society Standards:AFS Foundry Sand Handbook, 7th Edition43. Terminology3.1 Definitions:3.1.1 abrasive wearwear due to hard particles or hard protuberances
17、 forced against and moving along a solid surface(Terminology G40).NOTE 2This definition covers several different wear modes or mechanisms that fall under the abrasive wear category. These modes may degrade asurface by scratching, cutting, deformation, or gouging (1 and 2).54. Summary of Test Method4
18、.1 The dry sand/rubber wheel abrasion test (Fig. 1) involves the abrading of a standard test specimen with a grit of controlledsize and composition. The abrasive is introduced between the test specimen and a rotating wheel with a chlorobutyl rubber tireoror neoprene rubber rim of a specified hardnes
19、s. This test specimen is pressed against the rotating wheel at a specified force bymeans of a lever arm while a controlled flow of grit abrades the test surface. The rotation of the wheel is such that its contact facemoves in the direction of the sand flow. Note that the pivot axis of the lever arm
20、lies within a plane whichthat is approximatelytangent to the rubber wheel surface, and normal to the horizontal diameter along which the load is applied. The test duration andforce applied by the lever arm is varied as noted in Procedure A through E. Specimens are weighed before and after the test a
21、ndthe loss in mass recorded. It is necessary to convert the mass loss to volume loss in cubic millimetres, due to the wide differencesin 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
22、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 abrasive particle. In this practice these conditions arestandardized to develop a uniform condition of wear which has been referred to as scratchi
23、ng abrasion (1 and 3). The value of thepractice lies in predicting the relative ranking of various materials of construction in an abrasive environment. Since the practicedoes not attempt to duplicate all of the process conditions (abrasive size, shape, pressure, impact, or corrosive elements), it s
24、houldnot 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 similar relative order of merit as would occur in an abrasive environment. Volume loss data obtained from testmaterials whose lives are unknown in
25、 a specific abrasive environment may, however, be compared with test data obtained froma material whose life is known in the same environment. The comparison will provide a general indication of the worth of theunknown materials if abrasion is the predominant factor causing deterioration of the mate
26、rials.4 Available from American Foundrymens Society, Golf and Wolf Roads, Des Plaines, IL 60016.5 The boldface numbers in parentheses refer to a list of references at the end of this standard.FIG. 1 Schematic Diagram of Test ApparatusG65 1626. Apparatus and Material66.1 Fig. 2 shows a typical design
27、 and Fig. 3 and Fig. 4 are photographs of the test apparatus which may be constructed fromreadily available materials.Also, see Ref (3). Several elements are of critical importance to ensure uniformity in test results amonglaboratories. These are the type of rubber used on the wheel, the type of abr
28、asive and the shape, positioning and the size openingof the sand nozzle, and a suitable lever arm system to apply the required force.6.2 Rubber WheelThe wheel shown in Fig. 5 shall consist of a steel disk with an outer layer of chlorobutyl or neoprene rubbermolded to its periphery. Uncured rubber sh
29、all be bonded to the rim and fully cured in a steel mold. The optimum hardness of thecured rubber is DurometerA-60.Arange fromA58 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
30、in accordance 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 and Table 2. (See 9.9 for preparation and care of the rubber wheel before and after use andsee Fig. 2 and Fig.
31、5.)6.3 AbrasiveThe type of abrasive shall be a rounded quartz grain sand as typified by AFS 50/70 Test Sand (Fig. 6).7 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 result
32、s. Moisture content may be determined by measuring the weight loss after heatinga sample to approximately 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 s
33、and may be effectively storedin constant temperature and humidity rooms or in an enclosed steel storage bin equipped with a 100-W electric bulb. Welding6 Original users of this test method fabricated their own apparatus. Machines are available commercially from several manufacturers of abrasion test
34、ing equipment.7 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. 2 Dry Sand/Rubber Wheel Abrasion Test ApparatusG65 163electrode drying ovens, available from welding equipmen
35、t 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 (SpecificationE11).U.S. Sieve Size Sieve Opening % Retained on Sieve40 425 m (0.0165 in.) none50 300 m (0.0117 in.) 5
36、 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 andproper shape of sand curtain for test procedures. The nozzle may be of any convenient length that will allow for co
37、nnection 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 sand flow rate of 300 to 400 g/min. During use, the nozzle opening must be positioned asclose to the junction of t
38、he test specimen and the rubber wheel as the design will allow. (See Fig. 8.)6.4.1 Any convenient material of 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
39、of welding. Copper and steel are alsoused successfully.6.4.2 Formed NozzleNozzles formed from tubing may be 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 Fi
40、g.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).FIG. 3 Wheel and Lever ArmFIG. 4 Enclosure FrameG65 164FIG. 5 Rubber WheelTABLE 1 A Formula for Chlorobutyl RubberANOTE 1Specific gravity of mix: 1.15. Pressure cure: 20 min at 160C(320F).Materials
41、 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 ofalterna
42、tive suppliers, please provide this information to ASTM Headquarters. Yourcomments will receive 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 Durome
43、ter wheel will be in accordance with2BC615K11Z1Z2Z3Z4, where Z1ElastomerNeoprene GW, Z2Type ADurometer 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
44、 to minimize “heat-to-heat” variations.Materials Proportions by WeightNeoprene GW 100MagnesiaB 2Zinc OxideC 10Octamine 2Stearic Acid 0.5SRF Carbon BlackD 37ASTM #3 Oil 10A The sole source of supply known to the committee at this time is FalexCorporation, 1020 Airpark Dr., Sugar Grove, IL 60554. If y
45、ou are aware 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.BMaglite D (Merck)CKadox 16 (Ner Jersey Zinc)DASTM Grade N762G65 1656.4.4 Sand CurtainF
46、ig. 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 between the spe
47、cimen 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 load are suitable
48、.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 number of wheel
49、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 be available to apply theappropriate force (Table 23) between the test specimen and the wheel. The actual weight required should not be calculated, butrather should be determined by direct measurement by noting the load required to pull the spec
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