ASTM C838-1996(2005) Standard Test Method for Bulk Density of As-Manufactured Carbon and Graphite Shapes《加工炭精及石墨型材松密度的标准试验方法》.pdf

1、Designation: C 838 96 (Reapproved 2005)An American National StandardStandard Test Method forBulk Density of As-Manufactured Carbon and GraphiteShapes1This standard is issued under the fixed designation C 838; the number immediately following the designation indicates the year oforiginal adoption or,

2、 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 determination of the densityof as-manufactured carb

3、on and graphite from measurements ofmass and dimensions at room temperature.1.2 This test method is applicable to boronated carbon andgraphite.1.3 This test method is not applicable to carbon- andgraphite-containing materials that are thermally unstable at orbelow temperatures of 200C.1.4 The values

4、 stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.5 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 safet

5、y and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C 559 Test Method for Bulk Density by Physical Measure-ments of Manufactured Carbon and Graphite Articles3. Terminology3.1 Definitions of Terms Specific to This S

6、tandard:3.1.1 bulk density, nthe mass of a unit volume includingboth permeable and impermeable voids (and boron compoundsin the case of boronated carbon or boronated graphite) presentin the material at room temperature.4. Significance and Use4.1 This test method provides a means of determining bulkd

7、ensity on as-manufactured logs, blocks, or shaped articles.4.2 This test method is suitable for manufacturing controland acceptance specifications.4.3 Test Method C 559 may be used when a higher degreeof accuracy is required.5. Test Specimens5.1 Logs or BlocksMay be measured and weighed as-manufactu

8、red or after rough ends have been squared bymachining. The stock shall preferably have been indoors afterheat treatment; if there is doubt that the piece is dry, weigh, dry,and reweigh it. Repeat, if necessary, until there is less than0.1 % weight loss. The drying temperature should be from 110to 20

9、0C.5.2 Shaped ArticlesOther than right circular cylinders orrectangular parallelepipeds may be measured, and a correctionmade for the cavities or protuberances if the specimen volumecan be determined within 0.5 % (see 6.2).6. Procedure6.1 Logs or BlocksMeasure as-manufactured on the di-ameter or cro

10、ss section at two different locations, taking care toavoid distortions. Take four length measurements on cylinders90 apart on the periphery of the circular end faces. Onrectangular pieces, make four length measurements, two eachalong opposite faces. Make additional measurements, ifneeded, to determi

11、ne a valid mean for each dimension. Makedimensional and mass measurements with equipment accurateto 0.5 %.36.2 Shaped ArticlesMake dimensional and mass measure-ments with equipment accurate to 0.5 %.7. Calculation7.1 Calculate the bulk density as follows:D 5MVwhere:1This test method is under the jur

12、isdiction of Committee D02 on PetroleumProducts and Lubricants and is the direct responsibility of Subcommittee D02.F0 onManufactured Carbon and Graphite Products.Current edition approved Nov. 1, 2005. Published November 2005. Originallyapproved in 1980. Last previous edition approved in 2001 as C 8

13、38 96 (2001).2For 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.3Corrections of mass measurements for buoyancy e

14、ffects in air are generallynegligible for the accuracy obtained.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.D = density, kg/m3,M = mass, kg, andV = volume, m3.7.2 Calculate to three significant figures.8. Report8.1 Report the fol

15、lowing:8.1.1 Type, source, grade, geometry, and whether the speci-men is as-manufactured or machined.8.1.2 Densities of the individual specimens and the aver-ages.8.1.3 On shaped articles, other than right circular cylindersor rectangular parallelepipeds, the amount of volume correc-tion and method

16、of calculation used in 5.2.9. Precision and Bias49.1 Precision:9.1.1 A machined steel mass and an unmachined graphitebillet, both right circular cylinders, were circulated to fivelaboratories. Each laboratory utilized two independent observ-ers, each making a replicate set of measurements. Also, eac

17、hlaboratory was instructed to use normal industrial practice, thatis, no special calibration or precaution. The data were testedagainst the null hypothesis (no difference between labs) and therandom effects model for between-laboratory variance.9.1.2 Measurements on dimensions satisfied the null hy-

18、pothesis with a pooled coefficient of variation of 0.25 % for thecalculated volume. Masses, and hence densities, did not satisfythe null hypothesis. Within-laboratory coefficient of variationon density was 0.28 % and between-laboratory coefficient was0.81 %. Although the between-laboratory data indi

19、cated a bias,subsequent rechecking failed to identify such.9.1.3 These precision measures represent normal industrialpractice and do not indicate the precision attainable undercontrolled conditions.9.2 BiasNo statement on bias is derivable since the testswere performed with normal industrial practic

20、es and proce-dures.10. Keywords10.1 boronated; bulk; carbon; density; graphite; gravimet-ric; physicalASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that de

21、termination 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 five years andif not revised, either reapproved

22、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 technical committee, which you may attend. If you feel t

23、hat 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, PA 19428-2959,United States. Individual reprint

24、s (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).4Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: C05-1002.C 838 96 (2005)2