ANSI ASTM C1179-2015 Standard Test Method for Oxidation Mass Loss of Manufactured Carbon and Graphite Materials in Air.pdf

1、Designation: C1179 15 An American National StandardStandard Test Method forOxidation Mass Loss of Manufactured Carbon and GraphiteMaterials in Air1This standard is issued under the fixed designation C1179; the number immediately following the designation indicates the year oforiginal adoption or, in

2、 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. Scope*1.1 This test method provides a comparative oxidation massloss of manufactured carbon

3、and graphite materials in air.1.2 The values stated in SI units are to be regarded asstandard. 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 t

4、his standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Summary of Test Method2.1 The test method determines mass loss characteristics ofcarbon and graphite articles in air as a function of temperatureand time by s

5、ubjecting standard size specimens to mufflefurnace exposure and then comparing pre-test and post-testmass differentials.3. Significance and Use3.1 This test method is primarily concerned with the oxida-tion mass loss of manufactured carbon and graphite materialsin air at temperatures from 371 C to 6

6、77 C.3.2 The test method will provide acceptable results atpreselected test temperatures that yield less than 10 % massloss in 100 h. These results can be used to determine relativeservice temperatures.4. Interferences4.1 Results can be affected by materials released by thefurnace walls or furniture

7、. These materials may be present fromprevious oxidation test samples or other furnace use. It isrecommended that the furnace be operated at 1093 C for 1 hprior to use for oxidation mass loss testing.4.2 The validity of this test method depends upon theavailability of oxygen to the test specimen. The

8、 door of thefurnace shall be kept closed to maintain temperature control;however, the furnace door shall not be sealed, rendering thedoor airtight.4.3 Due to factors beyond the scope of the test method thatmight cause significant differences, this test method is onlyuseful for comparative results.5.

9、 Apparatus5.1 Muffle Furnace, with automatic temperature regulationwith 64C precision. Furnace chamber volume 983 cm3to2458 cm3.NOTE 1Commercially available muffle furnaces advertised to achieve611 C can be set up to achieve the necessary precision.5.2 Thermocouple, K-type (chromel/alumel with Type

10、304stainless steel sheath).5.3 Digital Thermometer, for temperature readout.5.4 Crucible Tongs.5.5 Glazed Crucibles, flat bottom.25.6 Quart Glass Tray, or equivalent.5.7 Nylon Gloves, lint-free.5.8 Paper, lint-free.5.9 Analytical Balance, with 0.001 g resolution.5.10 Desiccator, charged with indicat

11、ing desiccant.6. Sample Preparation6.1 All specimens are to be handled with lint-free nylongloves or equivalent during all machining, handling,impregnation, and testing. Specimens should be kept free ofcontamination by placing them on clean nonmetallic surfacesduring all operations. Once the specime

12、ns have been oxidized,direct handling is not recommended.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.F0 on Manufactured Carbon and Graphite Products.Current edition approved D

13、ec. 1, 2015. Published January 2016. Originallyapproved in 1991. Last previous edition approved in 2005 as C1179 91 (2010)1.DOI: 10.1520/C1179-15.2The sole source of supply of the crucible (Coors crucible 60048) known to thecommittee at this time is Coors Ceramics Co., 17750 W. 32nd Ave., Golden, CO

14、80401. If you are aware of alternative suppliers, please provide this information toASTM International Headquarters. Your comments will receive careful consider-ation at a meeting of the responsible technical committee,1which you may attend.*A Summary of Changes section appears at the end of this st

15、andardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States16.2 Test specimens are to consist of right cylinders 25.4 mmdiameter by 25.4 mm long 60.3 mm. Specimens are to bemachined all over with carbide-tipped tools to achieve asurface rou

16、ghness visually comparable to 0.8 m. arithmeticaverage (AA).6.3 Wipe specimens with lint-free paper to remove carbonmachining dust.6.4 Specimens and crucibles are to be clearly identified. Toavoid sample contamination, use a carbide-tipped scribe tomark the specimens. Crucibles can be marked with ce

17、ramicink.6.5 Place each specimen to be tested on its side (cylindricalsurface) in a dried, tared crucible. Specimens are to be kept inthe same crucible for the test duration. Record the individualidentification numbers for each specimen/crucible set.6.6 Dry the specimen/crucible sets in a vented ove

18、n at120 C to 150 C for a minimum of 2 h. Remove the specimen/crucible sets and cool in a desiccator for a minimum of 30 minto achieve room temperature.7. Procedure7.1 Before the running of this test method, the operatorshould practice the transferring of similar shaped specimensfrom furnace to desic

19、cator. The specimen/crucible set shouldbe transferred so that the specimen is exposed to the atmo-sphere for no longer than 30 s. The desiccator should be in theimmediate vicinity of the furnace.7.2 Preheat and stabilize the furnace to the designated testtemperature as verified by a monitoring therm

20、ocouple extend-ing 50 mm into the chamber from the rear furnace wall (seeFig. 1).7.3 Just before testing, remove the specimen/crucible setsfrom the desiccator and immediately weigh on an analyticalbalance to the nearest 0.001 g. Record this data as pretest mass.7.4 Place two preweighed replicate spe

21、cimen/crucible setson a quartz glass tray or equivalent and insert into the furnacechamber so that the monitoring thermocouple is approximatelycentered between the specimens. Specimens are to be 25 mm6 6 mm apart and centered on the monitoring thermocouple(see Fig. 1).7.5 Monitor the thermocouple re

22、ading and maintain furnacechamber temperature within 64 C of the designated testtemperature. Record the temperature readings from the moni-toring thermocouple on the data sheet for the following timesfor each test period:7.5.1 Just before inserting samples into furnace,7.5.2 1 h after start, and7.5.

23、3 Just before removing samples for weighing.7.6 Remove the specimen/crucible sets from the furnaceevery 25 h 61 h, for a total test time of 100 h, 615 min. Coolin a desiccator for a minimum of 30 min. Weigh the specimen/crucible set on an analytical balance to the nearest 0.001 g andrecord data as p

24、ost-test mass for the specific test time intervalat the designated test temperature.NOTE 1A medium weight insulating firebrick has been found to be satisfactory for this purpose.NOTE 2Small wedges of ceramic (broken) crucible pieces can be used to hold samples in place.FIG. 1 Views of Furnace Chambe

25、rC1179 1527.7 Repeat 7.4 through 7.6 for 100 h total test duration.8. Calculation8.1 Calculate the percent mass loss after each time intervaland post test as follows:% mass loss 5 100 3F1 2SB 2 TA 2 TDGwhere:A = pre-test specimen/crucible set mass,B = post-test specimen/crucible set mass, andT = cru

26、cible tare mass.9. Report9.1 Report the following information:9.1.1 Specimen identification, including material designa-tion and process lot number.9.1.2 Percent mass loss results for each specimen of 25 h,50 h, 75 h, and 100 h at designated test temperatures.10. Precision and Bias310.1 PrecisionThe

27、 precision of this test method wasdetermined via a round robin test among six laboratories. Twodifferent carbon materials were selected to verify the validity ofthe test method at lower and higher test temperatures. MaterialA, a carbon-graphite, was evaluated at 427 C and Material B,an electrographi

28、te, was evaluated at 538 C. All specimens ofeach material were from the same processing lot, with sixspecimens of each material evaluated by each laboratory.Evaluations were conducted in muffle furnaces from variousmanufacturers with chamber volumes ranging from 983 cm3to2458 cm3.10.2 The coefficien

29、t of variation for Material A within eachlaboratory was 0.1144 and between laboratories was 0.1140.For Material B, the coefficient of variation within each labo-ratory was 0.1804 and between laboratories was 0.4120.10.3 Testing was deliberately conducted with different ma-terials to demonstrate capa

30、bilities of the test method for bothlower and higher temperatures. The data shows that morevariability exists at the higher test temperatures. At these morereactive temperature regimes, furnace differences, temperaturecontrol variations, and the availability of oxygen must becarefully controlled to

31、ensure consistent results.10.4 BiasNo statement on bias can be made because thetrue value of the oxidation mass loss has not been established.11. Keywords11.1 air; carbon; graphite; oxidationAPPENDIX(Nonmandatory Information)X1. OXIDATION TEST DATA SHEETX1.1 Fig. X1.1 is an example of a typical repo

32、rt sheet fortest data.3Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:C05-1009.C1179 153SUMMARY OF CHANGESSubcommittee D02.F0 has identified the location of selected changes to this standard since the last issue(C1179 91 (2010)1

33、) that may impact the use of this standard. (Approved Dec. 1, 2015.)(1) Revised Keywords section.ASTM 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 determi

34、nation 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 or wi

35、thdrawn. 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 that y

36、our 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 reprints (si

37、ngle 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:/ X1.1 Sample Oxidation Test Data SheetC1179 154