1、Designation: C886 98 (Reapproved 2010)1An American National StandardStandard Test Method forScleroscope Hardness Testing of Carbon and GraphiteMaterials1This standard is issued under the fixed designation C886; the number immediately following the designation indicates the year oforiginal adoption o
2、r, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTEUpdated units of measurement throughout standard editorially in May 2010.1. Scope1.1
3、This test method covers the apparatus and procedure fordetermining the hardness of carbon and graphite materialsusing the Model C-2 scleroscope2with the hammer calibratedfor use on carbon and graphite materials with particles smallerthan 0.8 mm.31.2 The values stated in SI units are to be regarded a
4、sstandard. No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the
5、 applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:4E171 Specification for Atmospheres for Conditioning andTesting Flexible Barrier MaterialsE448 Practice for Scleroscope Hardness Testing of MetallicMaterials2.2 ANSI Standard:5ANSI C 64.1 Brushes for Ele
6、ctrical Machines3. Summary of Test Method3.1 The specimen is held in position, and the height ofrebound of a diamond-tipped hammer is observed and recordedas the hardness number.4. Significance and Use4.1 The scleroscope is a rebound hardness tester with a scaledivided into 140 equal parts. For carb
7、on and graphite materials,there is no established correlation between the Scleroscopehardness scale and other hardness scales. The test is useful inthe evaluation and the manufacturing control of carbon andgraphite materials.5. Interferences5.1 Lack of alignment of the instrument, as specified inSec
8、tion 10, will cause low readings.5.2 The specimen must be held firmly in position and musthave adequate support from the anvil on which the samplerests. Neglect of alignment, positioning, or support will resultin low readings.5.3 Rough surface finish, above 3175-nm AA, may causelow readings.5.4 Inde
9、ntations that are superimposed or spaced too closelytogether (approximately 3 mm) will cause incorrect readings.6. Apparatus6.1 Table, or equivalent, firm, for support.6.2 Scleroscope, Model C-2, equipped with a hammercalibrated by the manufacturer for use on carbon and graphitematerials.1This test
10、method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.F0 on Manufactured Carbon and Graphite Products.Current edition approved May 1, 2010. Published May 2010. Originallyapproved in 1988. Last previous edition a
11、pproved in 2005 as C886 98 (2005).DOI: 10.1520/C0886-98R10E01.2Registered trademark of the Shore Instrument and Manufacturing Co., Inc.,80-A Commercial St., Freeport, NY 11520, and available from Instron WorldwideHeadquarters, 825 University Ave., Norwood, MA 02062, .3This test method may be more re
12、adily understood by referring to the followingdocuments: Practice E448, ANSI C 64.1, Brushes for Electrical Machines, availablefromAmerican National Standards Institute, 1430 Broadway, New York, NY 10017,and Lysaght and DeBellis, Indentation Hardness Testing,American Chain and CableCorp., Reinhold P
13、ublishing Co., 1969.4For 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.5Available from American National Standar
14、ds Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.7. Test Specimen7.1 The specimen may be of any convenient size, but testsurfaces smaller than 5 by
15、5 mm are not recommended.7.2 The recommended specimen shall have a minimumthickness of 5 mm.7.3 The test surface shall not exceed 3175-nmAAin surfacefinish.7.4 The test surface-to-opposite side parallelism shall bewithin 1 %. For all specimens, the test surfaces must bemaintained normal to the axis
16、of the scleroscope tube.8. Calibration and Standardization8.1 Check the calibration of the scleroscope with carbon testblocks obtained from the instrument manufacturer.8.2 Make a series of tests on carbon test blocks that coverthe range of hardness to be tested.8.3 Make at least five tests on each c
17、arbon test block. Do notmake any tests closer than 6 mm from the sides of the testblocks.8.4 Consider the instrument calibrated if 90 % of the read-ings deviate no more than 64%,or63 points, whichever islarger, from the mean of the hardness numbers stamped on thecarbon test blocks.9. Conditioning9.1
18、 Allow the specimen to reach equilibrium with roomtemperature air, and test under the same conditions in accor-dance with Specification E171.9.2 Keep specimens free of contamination.10. Procedure10.1 Place the instrument on a firm support.10.2 Level the instrument using the plumb bob or bubblelevel.
19、10.3 Check the calibration in accordance with Section 8.10.4 Place the specimen on the anvil.10.5 Be certain that the hammer is in the “UP (locked)position.10.6 Lower the tube against the specimen, and hold firmly.10.7 Release the hammer and read the height of the re-bound.10.8 Return the hammer to
20、the “UP (locked) position.10.9 Repeat 10.6 through 10.8 four or more times, using adifferent impact point each time in accordance with 8.4.10.10 Record the average reading to the nearest wholenumber.10.11 A single reading substantially different from the othershall be reported, but not included in t
21、he average or standarddeviation calculations.11. Report11.1 Report the following information:11.1.1 Material identification,11.1.2 Specimen dimensions,11.1.3 Surface conditions, that is, as formed or machined,wet or dry,11.1.4 Orientation of the test surface with respect to anisot-ropy of material (
22、parallel or perpendicular),11.1.5 Number of readings taken,11.1.6 Average hardness reading to the nearest whole num-ber,11.1.7 Standard deviation where applicable,11.1.8 Testing conditions, including test date, serial numberof test machine, and operators name, and11.1.9 Special environmental conditi
23、ons, if any.12. Precision and Bias612.1 Precision among six laboratories is 63 points.12.2 Bias of a properly calibrated instrument is 64%,or63 points, whichever is larger.13. Keywords13.1 carbon; graphite; hardness; scleroscopeASTM International takes no position respecting the validity of any pate
24、nt rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision
25、at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comme
26、nts will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted
27、 by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-ma
28、il); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).6Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:C05-1005.C886 98 (2010)12
