1、Designation: C 708 08Standard Specification forNuclear-Grade Beryllium Oxide Powder1This standard is issued under the fixed designation C 708; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in p
2、arentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification defines the physical and chemicalrequirements of nuclear-grade beryllium oxide (BeO) powderto be used in fabricating nuclear co
3、mponents.1.2 This specification does not include requirements forhealth and safety.2,3,4It recognizes the material as a Class Bpoison and suggests that producers and users become thor-oughly familiar with and comply to applicable federal, state,and local regulations and handling guidelines.21.3 Spec
4、ial tests and procedures are given in Annex A1 andAnnex A2.1.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.2. Referenced Documents2.1 ASTM Standards:5C 373 Test Method for Water Absorption, Bulk Density,Apparent Porosity, an
5、d Apparent Specific Gravity of FiredWhiteware ProductsC 859 Terminology Relating to Nuclear MaterialsC 1233 Practice for Determining Equivalent Boron Con-tents of Nuclear MaterialsE11 Specification for Wire Cloth and Sieves for TestingPurposesE 105 Practice for Probability Sampling Of Materials2.2 A
6、NSI Standard:ANSI/ASME NQA-1 Quality Assurance Program Require-ments for Nuclear Facilities62.3 U.S. Government Standard:Title 10, Code of Federal Regulations, Energy Part 50(10CFR50) Domestic Licensing of Production and Utili-zation Facilities73. Terminology3.1 Definitions:3.1.1 Terms shall be defi
7、ned in accordance with Terminol-ogy C 859 except as defined in 3.2.3.2 Definitions of Terms Specific to This Standard:3.2.1 beryllium oxide powderBeO that contains no hardaggregates larger than No. 20 sieve designation (850 m).3.2.2 buyerorganization issuing the purchase order.3.2.3 calcinationproce
8、ss of heating a material to a hightemperature but without fusing in order to drive off volatilematter or to effect physical, chemical, or crystallographicchanges.3.2.4 powder lotthat quantity of beryllium-oxide powderprocessed such that samples taken in accordance with theprocedures of Section 8 can
9、 be considered as representative ofthe entire powder lot.3.2.5 sellerberyllium oxide powder supplier.4. Ordering Information4.1 The beryllium oxide powder must meet the chemical(Section 5) and physical (Section 6) requirements of thisspecification, based upon samples taken in accordance withSection
10、8. Deviation from these procedures and requirementsor additions to them must be agreed upon between the buyerand the seller.4.2 To be consistent with the requirements in 4.1, the buyermay specify the following information on the order:4.2.1 Quantity (weight of delivered product),4.2.2 Lot size,1This
11、 specification is under the jurisdiction of ASTM Committee C26 onNuclear Fuel Cycle and is the direct responsibility of Subcommittee C26.03 onNeutron Absorber Materials Specifications.Current edition approved Dec. 1, 2008. Published January 2009. Originallyapproved in 1983. Last previous edition app
12、roved in 1987 as C 708 87 which waswithdrawn November 1991 and reinstated in January 2009.2ICC Regulations, Tariff 12, Code of Regulations, Title 49, Office of the FederalRegister, National Archives and Record Services, General Services Administration,Washington, DC.3Breslin, A. J., arid Harris, W.
13、B., “Health Protection in Beryllium Facilities:Summary of 10 Years of Experience,” Health and Safety Laboratory, Vol 26, May1959.4Ferreira, L. E., “Recommended Practices for Safe Handling of Beryllium OxideCeramics,” Symposium on Materials and Electron Device Processing, ASTM STP300, ASTTA, 1961.5Fo
14、r 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.6Available from American National Standards Institute (ANSI), 25
15、 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.7Available from U.S. Government Printing Office Superintendent of Documents,732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/www.access.gpo.gov.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Co
16、nshohocken, PA 19428-2959, United States.4.2.3 Degree of calcination (optional),4.2.4 Nominal particle size range and applicable tolerancesin accordance with Specification E11 (U.S. Standard SieveSeries). For particle sizes smaller than No. 270 sieve designa-tion (53 m), the particle size distributi
17、on shall be agreed uponbetween the buyer and the seller, and4.2.5 Sampling requirements.5. Chemical Composition5.1 Beryllium-oxide powder is used for a variety of nuclearapplications. Depending upon end use, the purity requirementsmay be quite variable.5.2 Use analytical methods as agreed upon betwe
18、en thebuyer and the seller.5.3 Mass loss on dryinga5to10-g sample of the powder at110 6 5C for 1 h shall be 0.50 % maximum. After drying, themass loss on ignition of the sample at 1000 6 50C for 3 hshall be 1.0 % maximum.5.4 Impurity concentrations before drying (see 5.3) shall notexceed the limits
19、given in Table 1.5.5 Sample material (see 5.3) shall not exceed the impuritylimits given in Table 2.5.6 Other elements, in addition to those listed in Table 2,may be included in the buyers impurity content requirementsby mutual agreement between the buyer and the seller.5.7 The total equivalent boro
20、n content (EEC) of the impu-rities shall not exceed 9 g/g on a mass basis relative to BeO.The method of performing the calculation shall be as indicatedin Practice C 1233. The individual EBC values are calculatedas follows:EBC of impurity 5 EBC factor! 3 g of impurity/g BeO!where:EBC factor = (atomi
21、c mass of boron) 3 (sa impurity)/(atomic mass or impurity) 3 (sa boron), andsa = atomic absorption cross section in barns.5.7.1 Should the EBC of additional elements not listed inPractice C 1233 be of concern, their inclusion in the summa-tion and their respective EBC factors must be mutually agreed
22、upon between the buyer and the seller.6. Physical Requirements6.1 All of the beryllium-oxide shall be passed through a No.20 sieve designation (850 m) or equivalent.6.2 The powder shall be at least 99.5 mass % less than a No.100 sieve designation (150 m) determined by the wet sievetest in Annex A1 o
23、r other test mutually agreed upon betweenthe buyer and the seller.6.3 Beryllium-oxide powders may exhibit different bulk ortap densities, or both, due to different production methods. Theacceptable density values for nuclear grade BeO powder are asfollows:6.3.1 Bulk Density0.15 to 0.50 g/cm3, and6.3
24、.2 Tap Density0.30 to 1.00 g/cm3.6.4 SinterabilityTest pellets shall be produced and mea-sured in accordance with a sintering performance test agreedupon between the buyer and the seller. A sinterability perfor-mance test described in Annex A2 is presented as a guide.7. Cleanliness7.1 The powder lot
25、 shall be handled in a manner to avoidcontamination by foreign matter such as dust, cleaning agentsand organics, and materials such as plastics and paper used inpackaging. Cleaning solutions, if used, shall be free of halidesand nonvolatile additives and shall be removed from thepowder prior to samp
26、ling and packaging.8. Sampling8.1 Sampling plans to meet acceptance criteria and inspec-tion and measurement procedures that describe the method ofcompliance with this specification shall be established by theseller and submitted to the buyer for approval. The degree ofsampling where not specified i
27、n this specification, varies withthe application and for this reason should be specified on thepurchase order. Practice E 105 is referenced as a guide.8.2 Each sample taken shall be sufficient for quality verifi-cation tests, acceptance tests, referee tests, and achieve tests asneeded.8.3 Archive sa
28、mples shall be retained for a period of timespecified by the buyer and be delivered to the buyer uponrequest.8.4 Each sample shall be plainly marked with the following:8.4.1 Beryllium-oxide powder,8.4.2 Purchase order number,8.4.3 Purchase order specification,8.4.4 Gross, net, and tare weights,8.4.5
29、 Lot number, and8.4.6 Name of seller.8.5 Lot samples shall be prepared by blending and splittingthe container samples.8.5.1 To obtain a container sample, take specimens with athief at random locations along a randomly chosen verticalTABLE 1 Impurity Limits for Beryllium-Oxide PowderBefore DryingAEle
30、ment Maximum Concentration (g/g BeO)S 1500F 500Cl 100C 500P 300S+F+Cl+C+P 2000AAfter drying sample in accordance with 5.3.TABLE 2 Impurity Limits for Beryllium-Oxide PowderAfter IgnitionElement Maximum Concentration (g/g BeO)Al 100B3Cd 2Ca 50Cr 20Co 5Cu 10Fe 50Li 3Mg 100Mn 10Ni 15Si 150C708082traver
31、se through each container selected at random to besampled. Then blend the thief samples from the selectedcontainers and split down to the required size.8.5.2 The number of containers so sampled shall be 5 +(n/10), where n is the total number of containers per lotrounded to the nearest decade. If the
32、re are five or fewercontainers per lot, each container shall be so sampled.8.6 Package the lot sample so that no foreign material isintroduced into the powder during storage or shipment. Themethod of packaging shall be agreed upon between the buyerand the seller.8.7 Acceptance of the powder shall be
33、 on a lot basisprovided the material meets the requirements of this specifi-cation.9. Inspection and Certification9.1 The seller shall inspect the material covered by thisspecification and shall furnish the buyer with certificates oftests specified under Sections 5 and 6 showing the results oftestin
34、g and inspection performed for a powder lot.9.2 The results of all tests carried out by or on behalf of theseller including material sampling, size range, density, chemi-cal and impurity levels, visual appearance, sinterability, etc., inconformance with the requirements of this specification shallbe
35、 certified by the seller.10. Rejection10.1 Unless the buyer and seller agree otherwise, rejectionand acceptance shall be on a lot basis.10.2 Powder lots that fail to conform to the requirements ofthe specification may be rejected by the buyer. The seller maypetition the buyer to waive selected requi
36、rements for identifiedout-of-specification lots. Decision to grant such waiver belongsto the buyer. The seller may also apply any remedy to bringrejected lots into specification providing the seller can demon-strate to the buyer that such remedy does not impair thefunction or preclude the certificat
37、ion of the rejected material.10.3 In the event of disagreement over the results ofanalysis, samples shall be submitted to a mutually selectedreferee for resolution.11. Packaging and Shipping11.1 The powder shall be packaged in commercial vapor-tight nonhalogen bearing bags. The sealed bag shall beco
38、ntained in an outer container for shipping purposes. Theseller will be responsible for using a shipping container thatensures cleanliness, minimizes moisture pickup, provides ad-equate protection against damage during transportation, andensures reasonable ease of unpackaging.11.2 Each container shal
39、l be clearly marked with the fol-lowing:11.2.1 Beryllium oxide powder,11.2.2 Purchase order number,11.2.3 Purchase order specification,11.2.4 Gross, net, and tare weights,11.2.5 Lot number, and11.2.6 Name of seller.12. Quality Assurance12.1 Quality assurance requirements shall be agreed uponbetween
40、the buyer and the seller when specified in the purchaseorder. Code of Federal Regulations, Title 10, Part 50,AppendixB and ANSI/ASME NQA-1 are referenced as guides.ANNEXES(Mandatory Information)A1. WET SIEVE TESTA1.1 Place approximately 20 g of beryllium-oxide powderonto a 51 mm (2 in.) diameter pre
41、weighed sieve No. 100designation (150 m).A1.2 Both the powder and the sieve shall be dried at 150 65C.A1.3 Weigh the dry powder and sieve to nearest 1 mg.A1.4 Wet the powder carefully with a small portion ofwater from a wash bottle that has a fine dispensing tip and thatcontains 500 mL of warm water
42、. Wash the beryllium-oxidethrough the sieve with the remaining water while gentlyshaking the sieve.A1.5 Redry the sieve at 150 6 5C and reweigh. Theresidue retained on the sieve shall not exceed 0.5 mass % of theinitial sample.C708083A2. SINTERABILITY PERFORMANCE TESTA2.1 The purpose of the performa
43、nce test is to verify thesinterability of the beryllium-oxide powder. It is not intendedto simulate the buyers fabrication process.A2.2 All parameters of the performance test, once mutuallyestablished, between the buyer and the seller shall remainunchanged throughout the order.A2.3 Performance test
44、results shall be required for the lotsample pulled from the powder lot in accordance with thesampling procedure (Section 8). A minimum of five pelletsshall be required to constitute a valid performance test for apowder sample.A2.4 Density of the fired test pellets shall be determinedand shall not de
45、viate from the five pellet average by more than3.0 %. Results shall show a minimum density of 90 % oftheoretical density for each pellet. (The theoretical density ofBeO is 3.01 g/cm3.) Sintered pellet density shall be determinedby Test Method C 373 or demonstrated equivalent methodsagreed upon betwe
46、en the buyer and the seller.A2.5 Sinterability Test:A2.5.1 Cold press the sample. A binder or lubricant may beused in the pelletizing. Report the binder, lubricant, greendensity, compacting pressure, and dwell time.A2.5.2 Green dimensions of the test pellets shall be 12.7 60.375 mm diameter and the
47、length/diameter ratio shall be 0.75or greater. Report the type of press and pressing conditions.A2.5.3 Fire the pellets in one group (boat) in air for2hata temperature controlled to 625C in the range from 1500 to1625C. Report the sintering temperature and heating rateused. After cooling to room temp
48、erature determine the densityof the pellets.A2.5.4 The type of furnace used and atmosphere shall beidentical throughout all performance tests. Report firing sched-ules and actually observed “at temperature” data. Indicate thesource of the temperature measurement, that is, wall or boattemperature.AST
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