1、Designation: C561 16 An American National StandardStandard Test Method forAsh in a Graphite Sample1This standard is issued under the fixed designation C561; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、 A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope*1.1 This test method provides a practical determi
3、nation forthe ash content in a graphite sample.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
4、 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 Documents2.1 ASTM Standards:2C562 Test Method for Moisture in a Graphite Sample3. Terminology3.1 Definitions:3.1.1 ash, nin carbon
5、 and graphite technology, residueremaining after oxidation of a carbon or graphite.4. Significance and Use4.1 This test method provides a practical estimate of non-burnable residues in commercially available graphite materials.The ash values determined by this test method are of use incomparing the
6、relative purity of various grades of graphite. Tofacilitate use, this test method institutes simplifications thatpreclude the ability to determine absolutely the ash values ofthe test graphite material due to uncontrolled sources of tracecontamination.4.2 This test method is not intended for use in
7、determiningthe ash content of purified graphites, for example, nuclearmaterials. The relationship between the mineral content of agraphite sample and the ash content of that sample is unknownand is not determined by the application of this test method.5. Interferences5.1 Although permitted within th
8、e scope of this test method,the use of alumina ceramic crucibles may affect results due todifficulties in obtaining repeatable or proper weights, or both,because of (1) the hygroscopic nature of some ceramiccrucibles, and (2) the possible chemical combination of traceelements with the ceramic crucib
9、le.5.2 Any ash or trace elements introduced to the sample willinfluence results. Contamination can occur during drilling toobtain the sample and during pulverization. (See 7.1.)6. Apparatus6.1 Alumina Ceramic or Platinum Crucible or Dish, suit-able for holding sample (subsequently called sample hold
10、er).6.2 Analytical Balance, capable of weighing to 60.0002 g.6.3 Muffle Furnace, capable of reaching 950 C with con-troller capable of maintaining a temperature of 950 C 620 C.6.4 Platinum or Stainless Steel Wire.6.5 Desiccator, charged with indicating desiccant.6.6 Drying Oven, air convection type,
11、 capable of beingcontrolled to 110 C 6 2 C.7. Sampling7.1 Samples may be solid or particulate. Solid bodies maybe sampled by removing one or more solid pieces from thebody by, for example, sawing, turning, milling, or fracturing.Particulate samples may be generated from solid bodies bydrilling, usin
12、g a carbide drill to minimize contamination, or byother crushing and grinding methods.8. Procedure8.1 Dry the sample in accordance with Test Method C562,or for a minimum of 16 h in a drying oven at 110 C 6 2 C,and allow the sample to cool to room temperature in thedesiccator.1This test method is und
13、er 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 Jan. 1, 2016. Published February 2016. Originallyapproved in 1965. Last previous e
14、dition approved in 2010 as C561 91 (2010)1.DOI: 10.1520/C0561-16.2For 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 webs
15、ite.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States18.2 Tare a dried sample holder using an analytical balance to60.002 g. As soon as the sample has cooled to roomtemper
16、ature, remove it from the desiccator and weigh a 25 g to50 g sample into the tared sample holder. Reweigh the sampleand sample holder to 60.002 g.8.3 Introduce a slow stream of air into the muffle furnace(Note 1). Place the sample holder containing the sample intothe furnace, then heat the furnace s
17、o that the sample reaches500 C in 1 h and 750 C in 2 h.NOTE 1The stream of air into the furnace should be carefully adjustedso that the sample or ash will not be blown from the dish. The air streammay be admitted by leaving the door of the furnace open a slight amount.Exercise care when placing a sa
18、mple into a warm furnace so that nosample material will be lost due to drafts.8.4 To aid in oxidation, stir the sample periodically with thewire. The absence of black flecks indicates that ashing iscomplete; at that time raise the furnace temperature to 950 Cfor 1 h.8.5 Remove the dish containing th
19、e ash from the furnace,(see Note 1) and cool to room temperature in the desiccator.Following removal from the desiccator, weigh the dish with theash as rapidly as possible.8.6 Replace the sample in the furnace at 950 C for 30 minand repeat the procedure prescribed in 8.5 until a constantweight is ob
20、tained to 60.002 g.9. Calculation9.1 Calculate the percentage of ash as follows:Ash, % 5 C 2 A!/B 2 A!# 3100 (1)where:A = weight of the sample holder,B = weight of the sample holder and dried sample,C = weight of the sample holder and ash.10. Report10.1 The report shall include the following:10.1.1
21、Proper identification of the sample, and10.1.2 Results obtained from at least two ash determinationsand their averages.11. Precision and Bias311.1 The precision of this test method was determinedduring a round-robin test among four laboratories testingsamples split from a common sample which was gro
22、und to passa No. 60 (250 m) sieve. This sampling method was used forthe round-robin to minimize variations among samples pro-vided to participating laboratories.11.2 On this sample the mean, standard deviation betweenlaboratories and standard deviation within laboratories were,respectively:Mean 0.72
23、86 %Between laboratories 0.0159 %Within laboratories 0.0127 %11.3 No bias was noted during this round-robin test;however, the method is empirical and there is no suitablereference material that can be used to determine the bias of thistest method.12. Keywords12.1 ash; carbon; graphiteSUMMARY OF CHAN
24、GESSubcommittee D02.F0 has identified the location of selected changes to this standard since the last issue(C561 91 (2010)1) that may impact the use of this standard. (Approved Jan. 1, 2016.)(1) Added new Section 3, Terminology.ASTM International takes no position respecting the validity of any pat
25、ent 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
26、 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 comm
27、ents 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 copyrighte
28、d 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-m
29、ail); 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:C05-1008.C561 162
