1、Designation: C 753 04Standard Specification forNuclear-Grade, Sinterable Uranium Dioxide Powder1This standard is issued under the fixed designation C 753; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、 number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.INTRODUCTIONThis specification is intended to provide the nuclear industry with a general specification forsinterable uranium dioxide powder. It
3、recognizes the diversity of manufacturing methods by whichuranium dioxide powders are produced and the many special requirements for chemical and physicalcharacterization which may be imposed by the end use of the powder in a specific reactor system. Itis, therefore, anticipated that the buyer may s
4、upplement this specification with additional requirementsfor specific applications.1. Scope1.1 This specification covers nuclear-grade, sinterable ura-nium dioxide (UO2) powder. It applies to uranium dioxidepowder containing uranium of any235U concentration in theproduction of nuclear fuel pellets f
5、or use in nuclear reactors.1.2 This specification recognizes the presence of repro-cessed uranium in the fuel cycle and consequently definesisotopic limits for commercial grade UO2. Such commercialgrade UO2is defined so that, regarding fuel design andmanufacture, the product is essentially equivalen
6、t to that madefrom unreprocessed uranium. UO2falling outside these limitscannot necessarily be regarded as equivalent and may thusneed special provisions at the fuel fabrication plant or in thefuel design.1.3 This specification does not include provisions for pre-venting criticality accidents or req
7、uirements for health andsafety. Observance of this specification does not relieve theuser of the obligation to be aware of and conform to allinternational, national, or federal, state, and local regulationspertaining to possessing, shipping, processing, or using sourceor special nuclear material.1.4
8、 This specification refers expressly to calcined UO2powder before the addition of any die lubricant, binder, or poreformer. If powder is sold with such additions or prepared aspress feed, sampling procedures, allowable impurity contents,or powder physical requirements may need to be modified byagree
9、ment between the buyer and the seller.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 safety and health practices and determine the applica-bility of regulatory re
10、quirements prior to use.2. Referenced Documents2.1 ASTM Standards:2B 329 Test Method for Apparent Density of Metal Powdersand Compounds by the Scott VolumeterC 696 Test Methods for Chemical, Mass Spectrometric, andSpectrochemical Analysis of Nuclear-Grade Uranium Di-oxide Powders and PelletsC 859 Te
11、rminology Relating to Nuclear MaterialsC 996 Specification for Uranium Hexafluoride Enriched toLess than 5 %235UC 1233 Practice for Determining Equivalent Boron Con-tents of Nuclear MaterialsE 11 Specification for Wire-Cloth and Sieves for TestingPurposesE 105 Practice for Probability Sampling of Ma
12、terials2.2 ANSI Standard:3ANSI/ASME NQA-1 Quality Assurance Requirements forNuclear Facility Applications2.3 Federal Regulation:41This specification is under the jurisdiction of ASTM Committee C26 onNuclear Fuel Cycle and is the direct responsibility of Subcommittee C26.02 on Fueland Fertile Materia
13、l Specifications.Current edition approved June 1, 2004. Published July 2004. Originally approvedin 1973. Last previous edition approved in 1999 as C 753 99.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of AST
14、MStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.4Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave.,
15、 Philadelphia, PA 19111-5098.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Code of Federal Regulations, Title 10, Chapter 1, NuclearRegulatory Commission, Applicable Parts3. Terminology3.1 DefinitionsDefinitions of terms are as giv
16、en in Termi-nology C 859.4. Chemical Requirements4.1 Uranium ContentThe uranium content shall be deter-mined on a basis to be agreed upon between the buyer andseller.4.2 Oxygen-to-Uranium Ratio (O/U)The O/U ratio maybe specified as agreed upon between the buyer and seller. Thedetermination of the O/
17、U ratio shall be in accordance with TestMethods C 696 or a demonstrated equivalent.4.3 Impurity ContentThe impurity content shall not ex-ceed the individual element limit specified in Table 1 on auranium weight basis. The summation of the contribution ofeach of the impurity elements listed in Table
18、1 shall not exceed1500 g/gU. If an element analysis is reported as “less than” agiven concentration, this “less than” value shall be used in thedetermination of total impurities. If an element analysis isreported as “less than” a given concentration, this “less than”value shall be used in the determ
19、ination of total impurities.4.4 Moisture ContentThe moisture content shall not ex-ceed 0.40 weight percent of the powder.4.5 Isotopic Content:4.5.1 For UO2powder with an isotopic content of235Ubetween that of natural uranium and 5 %, the isotopic limits ofSpecification C 996 shall apply, unless othe
20、rwise agreed uponbetween the buyer and the seller. If the236U content is greaterthan Enriched Commercial Grade UF6requirements, the iso-topic analysis requirements of Specification C 996 shall apply.The specific isotopic measurements required by SpecificationC 996 may be waived, provided that the se
21、ller can demonstratecompliance with Specification C 996, for instance, through thesellers quality assurance records. A236U content greater thanthat specified in C 996 for Enriched Commercial Grade UF6may be agreed between the buyer and the seller since it is nota safety concern.54.5.2 For UO2powder,
22、 not having an assay in the range setforth in 4.5.1, the isotopic requirements shall be as agreed uponbetween the buyer and the seller.4.6 Equivalent Boron ContentFor thermal reactor use, thetotal equivalent boron content (EBC) shall not exceed 4.0 g/gon a uranium weight basis. For purpose of EBC ca
23、lculation B,Gd, Eu, Dy, Sm, and Cd shall be included in addition toelements listed in Table 1. The method of performing thecalculation shall be as indicated in Practice C 1233. For fastreactor use, the above limitation on EBC does not apply.4.7 Cleanliness and WorkmanshipThe powder shall bevisually
24、free of foreign material such as metallic particles andoil.5. Physical Requirements5.1 Particle SizeBased on visual observation, all of arepresentative sample of the UO2shall pass through a 425-m(No. 40) standard sieve conforming to Specification E 11.Particle size distribution and method of determi
25、nation shall beas agreed upon between the buyer and seller. Alternatively, asagreed upon between the buyer and the seller, the fraction notpassing through a 425-m (No. 40) standard sieve shall bereported to the buyer.5.2 Bulk DensityThe bulk density of UO2powder willdepend on the processing method.
26、Unless otherwise agreedupon between the buyer and seller, the bulk density shall be aminimum of 0.625 kg/m3as determined by Test Method B 329,or an agreed upon alternative.NOTE 1For powder prepared as a press feed, a minimum bulk densityof 1.8 g/cm3is recommended.5.3 Sinterability Test pellets shall
27、 be produced and mea-sured in accordance with a sintering performance test agreedupon between the buyer and seller. A sinterability performancetest described in Appendix X1 is presented as a guide.6. Sampling6.1 A lot is defined as a quantity of UO2powder that isuniform in isotopic, chemical, physic
28、al, and sinterability char-acteristics.6.2 The identity of a lot shall be retained throughout itsprocessing history.6.3 A powder lot shall form the basis for defining samplingplans used to establish conformance to this specification.6.4 Sampling plans and procedures shall be mutually agreedupon by t
29、he buyer and the seller. Analytical confirmation ofsampling plans shall be documented as part of the manufac-turers quality assurance and nuclear materials control andaccountability program.5The intent of the C 996 isotope limits is to indicate possible presence ofreprocessed UF6. Acceptance of UO2p
30、ellets with236U content above that specifiedfor Enriched Commercial Grade UF6, shall be based on fuel performance evalua-tion.TABLE 1 Impurity Elements and Maximum Concentration LimitsElementMaximum ConcentrationLimit of Uranium, g/gUAluminum 250Carbon 100Calcium + magnesium 200Chlorine 100Chromium
31、200Cobalt 100Copper 250Fluorine 100Iron 250Lead 250Manganese 250Molybdenum 250Nickel 200Nitrogen 200Phosphorus 250Silicon 300Tantalum 250ThoriumA10Tin 250Titanium 250Tungsten 250Vanadium 250Zinc 250AThorium is primarily of concern because of the reactor production of233U.C7530426.5 UO2may be hygrosc
32、opic and retain sufficient waterafter exposure to a moist atmosphere to cause detectable errors.Sample, weigh, and handle the sample under conditions thatwill ensure that the sample is representative of the lot.7. Test Methods7.1 The seller shall test the sample to ensure conformance ofthe powder to
33、 the requirements of Sections 4 and 5.7.1.1 All chemical analyses shall be performed on portionsof the representative sample. Analytical chemistry methodsused shall be in accordance with Test Methods C 696 ordemonstrated equivalent methods agreed upon between thebuyer and seller.7.2 Lot Acceptance A
34、cceptance testing may be performedby the buyer on either the sample provided by the seller or asample taken at the buyers plant by sampling one or moreindividual containers with a thief. Practice E 105 is referencedas a guide. Acceptance shall be on a lot basis and shall becontingent upon the materi
35、al properties meeting the require-ments of Sections 4 through 6.7.3 Referee Method The buyer and seller shall agree to athird party as a referee in the event of a dispute in analyticalresults.8. Certification8.1 The seller shall provide to the buyer documents certify-ing:8.1.1 The isotopic content a
36、nd identity of the startingmaterial lot and8.1.2 That the powder meets all the requirements of Sec-tions 4 through 6.8.2 Test data on the following characteristics shall besupplied upon request:8.2.1 Uranium isotopic content,8.2.2 Uranium content,8.2.3 Individual impurity levels,8.2.4 Moisture conte
37、nt,8.2.5 Sinterability test results,8.2.6 O/U ratio,8.2.7 Particle size distribution, and8.2.8 Bulk density.9. Packaging and Package Marking9.1 Uranium dioxide powder shall be packaged in sealedcontainers to prevent loss of material and undue contaminationfrom air or the container materials. The exa
38、ct size and methodof packaging shall be as agreed upon by the buyer and seller.9.2 Each container shall bear, as a minimum, a label on thelid and side with the following information:9.2.1 Sellers name,9.2.2 Material in container,9.2.3 Lot number,9.2.4 Uranium enrichment,9.2.5 Gross, tare, net oxide
39、weights,9.2.6 Uranium weight,9.2.7 Purchase order number, and9.2.8 Container ( ) of ( ).10. Quality Assurance10.1 Quality Assurance requirements shall be as agreedupon between the buyer and seller when specified in thepurchase order. Code of Federal Regulations, Title 10, Part 50,Appendix B and ANSI
40、/ASME NQA-1 are referenced asguides.11. Keywords11.1 nuclear fuel; powder; urania; uranium dioxideAPPENDIX(Nonmandatory Information)X1. SINTERABILITY TESTX1.1 PurposeX1.1.1 The purpose of the sinterability test is to verify thefabricability of each lot of UO2powder. Although not required,it is desir
41、able to simulate the buyers pellet fabrication processto improve the predictability of the powder. A suggestedsinterability test follows.X1.2 Fabrication of Test PelletsX1.2.1 Preparation of Test PelletsCold press powder withthe addition of agreed upon quantities of lubricant or additiveto produce a
42、t least fifteen green pellets within a predetermineddensity range approximating the buyers target range. Thedensity of each pellet shall vary no more than 60.5 %theoretical density (TD) from the average of the required testpellets. The type of pellet press, pressing conditions, die taper,use and qua
43、ntity of any lubricant or additive (if used), powderpreconditioning, dwell time, and any other relevant pressingconditions shall be approved by the buyer. Report the averagegreen density and pressing pressure for each pellet.X1.2.2 The diameter and length-to-diameter ratio of theunfired test pellets
44、 shall be approximately that of the buyersunfired production pellets. The length of each unfired pelletshall vary no more than 60.5 mm (60.02 in.).X1.2.3 Fire the pellets as one batch in hydrogen or dissoci-ated ammonia at a predetermined temperature set point (typi-cally 1625 to 1750C, with a tempe
45、rature control of 625C)for 2 to 6 h, approximating the buyers sintering conditions.The type of furnace used, atmosphere including dew point, andactual sintering cycle shall be as agreed upon between thebuyer and the seller.X1.2.4 Once established, all of the parameters of this testshall remain uncha
46、nged throughout all lots of the order.C753043X1.3 Density DeterminationX1.3.1 Determine the geometrical density of the unfired andfired, but unground pellets as follows:X1.3.1.1 DiameterRecord the average of four readingstaken to the nearest 0.005 mm (0.0002 in.) at equally spacedintervals along the
47、 length of the pellet using a blade microme-ter or equivalent gauge.X1.3.1.2 LengthRecord the average of three readingstaken to the nearest 0.005 mm (0.0002 in.) from end to end ofthe pellet at equally spaced intervals along a vertically bisect-ing plane using a micrometer or equivalent gauge.X1.3.1
48、.3 WeightRecord the pellet weight to the nearest0.001 g.X1.3.1.4 DensityCalculate the density of each pellet tothe nearest 0.01 g/cm3. The geometric density calculationshould account for known biases due to pellet geometry effectsand should be qualified by demonstrated equivalency with animmersion t
49、echnique.X1.3.2 Alternatively, the density of the pellet may beobtained by an immersion technique or demonstrated equiva-lent method as agreed upon between the buyer and the seller.X1.4 Sintered Pellet Performance TestX1.4.1 Make the sinterability test using at least fifteenpellets produced from each lot. Determine the density of eachpellet, and verify that each pellet is within 62.0 % of theaverage and not less than 94.0 % TD. The minimum sintereddensity should account for test additives (if used) and approxi-mate the buyers nominal pellet density r
