1、Designation: C 1076 09Standard Specification forNuclear Grade Hafnium Oxide Pellets1This standard is issued under the fixed designation C 1076; 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
2、parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification applies to pellets of stabilized cubichafnium oxide used in nuclear reactors.1.2 The values stated in SI units are to be regar
3、ded as thestandard. The values given in parentheses are for informationonly.2. Referenced Documents2.1 ASTM Standards:2C 559 Test Method for Bulk Density by Physical Measure-ments of Manufactured Carbon and Graphite ArticlesC 859 Terminology Relating to Nuclear MaterialsC 1098 Specification for Nucl
4、ear-Grade Hafnium OxidePowderE 105 Practice for Probability Sampling Of Materials2.2 ANSI Standard:3ANSI/ASME NQA-1 Quality Assurance Requirements forNuclear Facility Applications2.3 U.S. Government Document:4Code of Federal Regulations, Title 10, Part 50Energy(10CFR 50) Domestic Licensing of Produc
5、tion and Utili-zation Facilities3. Terminology3.1 DefinitionsTerms shall be defined in accordance withTerminology C 859 except for the following:3.1.1 buyerorganization issuing the purchase order.3.1.2 pelletfabricated geometric shape of stabilized cubichafnium oxide having a chemical composition as
6、 described inSection 4.3.1.3 pellet lotthe pellets produced from one hafniumoxide powder lot using one set of process parameters. Pellet lotsize shall be agreed upon between the seller and the buyer.3.1.4 phase transformationrearrangement of the atomicordering of a crystalline lattice as a material
7、is cycled througha critical transformation or inversion temperature. The changefrom one crystalline phase to another may be accompanied bya volume change that could lead to cracks or defects in articlesfabricated from such materials.5,63.1.5 powder lota specified quantity of hafnium oxidepowder with
8、 stabilizing additive, blended together such thatsamples taken in accordance with Section 7 can be consideredas representative of the entire quantity.3.1.6 sellerhafnium oxide pellet supplier.3.1.7 stabilizing additivea material which, when presentin sufficient concentration in the subject material
9、exhibiting thephase transformation, produces a stabilized crystalline phasethat does not undergo a transformation or inversion at anytemperature within the expected fabrication or usage regime ofthe manufactured pellet. The potentially deleterious volumechange is therefore avoided.4. Chemical Compos
10、ition4.1 The starting hafnium oxide powder shall be in accor-dance with Specification C 1098.4.2 A stabilizing additive shall be utilized with the hafniumoxide. The recommended stabilizing additive is yttrium oxide(Y2O3). The typical concentration range is 7 to 10 weight %Y2O3in the finished product
11、. References to other stabilizingadditives (such as calcium oxide (CaO) and magnesium oxide(MgO) may be found in the literature and these additives maybe used if agreed upon by the buyer and seller. It is cautioned,however, that the buyer should be aware of potential destabi-lization during thermal
12、cycling when MgO or CaO is used.4.3 Use analytical chemistry methods as agreed upon be-tween the buyer and the seller.1This specification is under the jurisdiction of ASTM Committee C26 onNuclear Fuel Cycle and is the direct responsibility of Subcommittee C26.03 onNeutron Absorber Materials Specific
13、ations.Current edition approved July 1, 2009. Published August 2009. Originallyapproved in 1987. Last previous edition approved in 2004 as C 1076 97 (2004).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Sevice at serviceastm.org. For Annual Book of ASTM
14、Standardsvolume 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, http:/www.ansi.org.4Available from U.S. Government Printing Office Superintendent of Documents,732
15、N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/www.access.gpo.gov.5Curtis, C. E., Doney, L. M., and Johnson, J. R., “Some Properties ofHafnium-Oxide, Hafnium-Silicate, Calcium-Hafnate, and Hafnium-Carbide,” Jour-nal of American Ceramics Society, Vol 37, 1954, pp. 458465.6Brown, L. M
16、., and Madiyasni, K. S., “Characterization of Alkoxy-DerivedYttria-Stabilized Hafnia,” Journal of American Ceramics Society, Vol 53, 1970, pp.590594.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.4 The hafnium concentration, in gr
17、ams of hafnium perunit volume or grams of hafnium per unit length, may bespecified by the buyer. In specifying the allowable range inhafnium concentration, the buyer should consider the follow-ing:4.4.1 Variations in chemical composition,4.4.2 Pellet bulk density,4.4.3 Type and concentration of stab
18、ilizing additive, and4.4.4 Pellet dimensions and dimensional tolerances.4.5 The impurity concentration, excluding zirconia and thestabilizing additive, shall not exceed 0.5 weight %. Individualelement limits are specified in Table 1. The buyer may specifyadditional limits for any elements not listed
19、 in Table 1.4.6 The zirconium concentration shall not exceed 4.5weight % on the basis of Zr/(Zr + Hf).4.7 The moisture concentration limit is included in the totalhydrogen limit (see Table 1).5. Physical Requirements5.1 Physical Dimensions:5.1.1 Dimensional requirements shall be in accordance withap
20、plicable drawings and purchase order documents.5.1.2 Pellet dimensions shall be measured to ensure com-pliance with the buyers requirements. Sampling plans to meetthe acceptance criteria shall be agreed upon between the buyerand the seller to ensure that the pellets represented by thesample are with
21、in the required tolerance.5.2 Density:5.2.1 Pellet density limits shall be specified by the buyer.The incorporation of a stabilizing additive will introduce achange in the theoretical density of the fabricated pellets andshould be taken into account. The method of establishing thetheoretical density
22、 value shall be mutually agreed upon be-tween the buyer and the seller.5.2.2 The method of density measurement shall be TestMethod C 559 or an alternative method submitted by the sellerfor approval by the buyer. Sampling plans to meet theacceptance criteria shall be agreed upon between the buyer and
23、the seller. The method of density measurement and the methodof compliance with 5.2.1 shall be approved by the buyer priorto use.5.3 Mechanical PropertiesRequired mechanical proper-ties and test methods shall be mutually agreed upon betweenthe buyer and the seller. It is recommended that the plan ofm
24、echanical testing to verify pellet integrity include compres-sion testing at 69 MPa (10 000 psi).5.4 Phase StabilizationA crushed sample of the firedproduct shall be tested by powder X-ray diffraction. Thediffraction pattern must show that the required cubic crystallinephase has been developed in th
25、e product. The criteria forsatisfactory development of the cubic phace shall be mutuallyagreed upon between the buyer and the seller.5.5 Visual AppearanceVisual examination shall be con-ducted on finished pellets in accordance with Section 7 onSampling. The method of defect measurement shall be ap-p
26、roved by the buyer prior to use representing the requirementsof 5.5.1, 5.5.2, and 5.5.3. These standards shall be used asacceptance standards for the visual examination of the pellets.In the event of a dispute, the method of defect measurementshall be submitted by the seller for approval by the buye
27、r.Maximum permissible defects are defined as follows:5.5.1 End ChipsPellet-end surface shall not be chippedbeyond 10 % of the end-face surface area and no chip shallexceed 1.02 mm (0.040 in.) in depth.5.5.2 Circumferential ChipsPellet circumferential sur-faces shall not be chipped beyond 5 % of the
28、circumferentialsurface area. No single chip shall exceed a depth of 1.02 mm(0.040 in.).5.5.3 CracksCracks are acceptable, providing the totallength of all cracks does not exceed 90 degrees of circumfer-ence, and other requirements of the specification are met.5.5.4 Fissures and other defects shall b
29、e evaluated withrespect to the criteria of 5.5.1, 5.5.2, and 5.5.3.6. Cleanliness6.1 The finished pellets shall be handled in a manner toavoid contamination by grinding fluids and dust, cleaningagents, and organic materials such as plastics and paper used inpackaging. Cleaning solutions, if used, sh
30、all be free of halidesor non-volatile additives and shall be removed from the pelletsprior to sampling and packaging.7. Sampling7.1 Sampling plans to meet the acceptance criteria andinspection and measurement procedures that describe themethod of compliance with this specification shall be approvedb
31、y the buyer. The degree of sampling varies with the applica-tion and for this reason should be specified on the purchaseorder. Practice E 105 is referenced as a guide.7.2 Powder and pellet samples shall be taken for qualityverification tests, acceptance tests, referee tests and archivesamples, as ne
32、eded.7.3 Archive samples shall be retained and disposed of inaccordance with the buyers instructions.8. Inspection and Certification8.1 The seller shall inspect the material covered by thisspecification and shall furnish the buyer with certificates of testshowing the results of testing and inspectio
33、n performed oneach pellet lot prior to shipment. The seller shall certify thateach pellet lot is in compliance with the provisions of thisspecification.TABLE 1 Impurity Concentration LimitsElementMaximumConcentrationLimit (g/g Pellet)B 400C 1 000Gd 200Gd+Sm+Eu+Dy 500Co 100Si 2 000Th 400F3F+Cl+Br+I 1
34、00H (total hydrogen from all sources) 2C10760929. Rejection and Rehearing9.1 Unless the buyer and the seller agree otherwise, rejec-tion and acceptance shall be on a pellet lot basis.9.2 Pellet lots that fail to conform to the requirements of thisspecification may be rejected by the buyer. The selle
35、r maypetition the buyer to waive selected requirements 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 no
36、t impair thefunction or preclude the certification of the rejected material.9.3 In the event of disagreement over the results of analysis,samples shall be submitted to a mutually selected referee forresolution.10. Packaging and Shipping10.1 The pellets shall be packaged in sealed containers topreven
37、t loss or damage, or both, of material and contaminationfrom airborne or container materials. The exact size and type ofpackaging shall be as mutually agreed upon between the buyerand seller.10.2 Each container shall be clearly marked with the fol-lowing:10.2.1 Hafnium oxide pellets plus stabilizing
38、 additive,10.2.2 Purchase order number,10.2.3 Gross, tare, and net weight,10.2.4 Lot number, and10.2.5 Name of pellet manufacturer.11. Quality Assurance11.1 Quality assurance requirements shall be agreed uponbetween the buyer and the seller when specified in the purchaseorder. Code of Federal Regula
39、tions, Title 10, Part 50 (Appen-dix B) and ANSI/ASME NQA-1 are referenced as guides.12. Keywords12.1 CaO; hafnium oxide; MgO; stabilizer; stabilizing;additive; thermal cycling test; Y2O3ASTM International takes no position respecting the validity of any patent rights asserted in connection with any
40、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 at any time by the responsible technical c
41、ommittee 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 comments will receive careful consideration at
42、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 copyrighted by ASTM International, 100 Barr Harbor Dr
43、ive, 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-mail); or through the ASTM website(www.astm.org).C1076093
