1、Designation: C 886 98 (Reapproved 2005)An American National StandardStandard Test Method forScleroscope Hardness Testing of Carbon and GraphiteMaterials1This standard is issued under the fixed designation C 886; the number immediately following the designation indicates the year oforiginal adoption
2、or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the apparatus and procedure fordetermining the hardn
3、ess 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 (0.032 in.).31.2 The values given in acceptable metric units are to beregarded as the standard. The values given in parentheses are
4、provided for information purposes only.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 applica-bility of regulatory l
5、imitations prior to use.2. Referenced Documents2.1 ASTM Standards:4E 171 Specification for Standard Atmospheres for Condi-tioning and Testing Flexible Barrier MaterialsE 448 Practice for Scleroscope Hardness Testing of MetallicMaterials2.2 ANSI Standard:5ANSI C 64.1 Brushes for Electrical Machines3.
6、 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 carbon and graphite ma
7、terials,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 inSection 10, will caus
8、e 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 (125-in.) AA,may cause low readings.5.4 Indentations
9、 that are superimposed or spaced too closelytogether (approximately 3 mm (18 in.) will cause incorrectreadings.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 Spec
10、imen7.1 The specimen may be of any convenient size, but testsurfaces smaller than 5 by 5 mm (0.2 by 0.2 in.) are notrecommended.7.2 The recommended specimen shall have a minimumthickness of 5 mm (0.2 in.).1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubr
11、icants and is the direct responsibility of SubcommitteeD02.F0 on Manufactured Carbon and Graphite Products.Current edition approved May 1, 2005. Published May 2005. Originallyapproved in 1988. Last previous edition approved in 1998 as C 886 98.2Registered trademark of the Shore Instrument and Manufa
12、cturing Co., Inc.,80-A Commercial St., Freeport, NY 11520.3This test method may be more readily understood by referring to the followingdocuments: Practice E 448,ANSI C 64.1, Brushes for Electrical Machines, availablefromAmerican National Standards Institute, 1430 Broadway, New York, NY 10017,and Ly
13、saght 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 Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the st
14、andards Document Summary page onthe ASTM website.5Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.7.3 The test surface shall no
15、t exceed 3175-nm (125-in.)AA in surface finish.7.4 The test surface-to-opposite side parallelism shall bewithin 1 % (0.010 % per linear inch). For all specimens, thetest surfaces must be maintained normal to the axis of thescleroscope tube.8. Calibration and Standardization8.1 Check the calibration
16、of the Scleroscope with carbontest blocks 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 (0.25 in.) from the sides of
17、 thetest blocks.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 te
18、st under the same conditions in accor-dance with Specification E 171.9.2 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 s
19、pecimen 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 tim
20、es, 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 f
21、ollowing 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 Averag
22、e 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 conditions, if any.12. Precision and Bias612.1 Precision among six laboratories
23、 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 patent rights asserted in connection with any item mentionedin this standard
24、. 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 at any time by the responsible technical committee and must be reviewed
25、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 comments will receive careful consideration at a meeting of theresponsible te
26、chnical 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 Conshoh
27、ocken, 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).6Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: C051005.C 886 98 (2005)2
