1、Designation: C886 98 (Reapproved 2015) An 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.1. Scope1.1 This test method covers the apparatus and procedure fordetermining the hardnes
3、s 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 asstandard. No other units of measurement are included in thisstandard.1.3 This
4、 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 applica-bility of regulatory limitations prior to use.2. Referenced Documents
5、2.1 ASTM Standards:4E171 Practice for Conditioning and Testing Flexible BarrierPackagingE448 Practice for Scleroscope Hardness Testing of MetallicMaterials2.2 ANSI Standard:5ANSI C 64.1 Brushes for Electrical Machines3. Summary of Test Method3.1 The specimen is held in position, and the height ofreb
6、ound 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 carbon and graphite materials,there is no established correlation between the Scleroscopehardness scale
7、 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 inSection 10, will cause low readings.5.2 The specimen must be held firmly in position and musthave adeq
8、uate 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 Indentations that are superimposed or spaced too closelytogether (approximately 3 mm) will cause incorr
9、ect 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.7. Test Specimen7.1 The specimen may be of any convenient size, but testsurfaces smaller than 5 mm by 5 mm are
10、 not recommended.7.2 The recommended specimen shall have a minimumthickness of 5 mm.7.3 The test surface shall not exceed 3175 nm AA in surfacefinish.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility
11、ofSubcommittee D02.F0 on Manufactured Carbon and Graphite Products.Current edition approved Oct. 1, 2015. Published December 2015. Originallyapproved in 1988. Last previous edition approved in 2010 as C886 98 (2010)1.DOI: 10.1520/C0886-98R15.2Registered trademark of the Shore Instrument and Manufact
12、uring 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 readily understood by referring to the followingdocuments: Practice E448, ANSI C 64.1, Brushes for Electrical Machines, av
13、ailablefromAmerican National Standards Institute, 1430 Broadway, New York, NY 10017,and Lysaght and DeBellis, Indentation Hardness Testing,American Chain and CableCorp., Reinhold Publishing Co., 1969.4For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Servic
14、e at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.5Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.Copyright ASTM International, 100
15、Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States17.4 The test surface-to-opposite side parallelism shall bewithin 1 %. For all specimens, the test surfaces must bemaintained normal to the axis of the scleroscope tube.8. Calibration and Standardization8.1 Check the cali
16、bration 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 carbon test block. Do notmake any tests closer than 6 mm from the sides of th
17、e 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 Allow the specimen to reach equilibrium with roomtemperature air, and test
18、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.10.3 Check the calibration in accordance with Section 8.10.4 Place the speci
19、men 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 the “UP (locked) position.10.9 Repeat 10.6 through 10.8 four or more times,
20、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 the average or standarddeviation calculations.11. Report11.1 Report the follo
21、wing 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 (parallel or perpendicular),11.1.5 Number of readings taken,11.1.6 Average ha
22、rdness reading to the nearest wholenumber,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 conditions, if any.12. Precision and Bias612.1 Precision among six laboratories is 63
23、 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 patent rights asserted in connection with any item mentionedin this standard. User
24、s 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 at any time by the responsible technical committee and must be reviewed every
25、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 comments will receive careful consideration at a meeting of theresponsible technica
26、l 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 by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken,
27、 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-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:C05-1005.C886 98 (2015)2
