1、Designation: C 751 07Standard Specification forNuclear-Grade Boron Carbide Pellets1This standard is issued under the fixed designation C 751; 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 pa
2、rentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification applies to boron carbide pellets foruse as a control material in nuclear reactors.1.2 The values stated in SI units are to be r
3、egarded 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 750 Specification for Nuclear-Grade Boron Carbide Pow-derC 791 Test Me
4、thods for Chemical, Mass Spectrometric, andSpectrochemical Analysis of Nuclear-Grade Boron Car-bideC 859 Terminology Relating to Nuclear Materials3E 105 Practice for Probability Sampling Of Materials2.2 ANSI Standard:ANSI/ASME NQA-1 Quality Assurance Program Require-ments for Nuclear Facilities42.3
5、U.S. Government Document:Title 10, CFR, Energy Part 50 (10 CFR 50) Licensing ofDomestic Production and Utilization Facilities53. Terminology3.1 Terms shall be defined in accordance with TerminologyC 859, except for the following:3.2 buyerthe organization issuing the purchase order.3.3 pellet lotthat
6、 quantity of pellets produced from oneboron carbide powder lot using one set of process parameters.The pellet lot size shall be agreed upon between seller andbuyer.3.4 powder lota fixed quantity of boron carbide powderblended together such that samples taken in accordance withSection 7 on Sampling c
7、an be considered as representative ofthe entire fixed quantity.3.5 sellerthe boron carbide pellet supplier.4. Chemical Composition4.1 The starting boron carbide powder used to produce thesepellets shall be in accordance with Specification C 750.4.2 Analytical chemistry methods used to test pellets f
8、orconformance with this specification shall be those of MethodC 791 or demonstrated equivalent methods agreed upon be-tween buyer and seller.4.3 The10B concentration (gram10B per unit volume orgrams10B per unit length) may be specified by the buyer. Thebuyer should consider the following in specifyi
9、ng the allow-able range in10B concentration:4.3.1 Variations in chemical composition,4.3.2 Bulk pellet density,4.3.3 Boron isotopic composition, and4.3.4 Pellet dimensions.4.4 The finished boron carbide pellets shall conform to thechemical analysis in Table 1.5. Physical Requirements Physical Requir
10、ements5.1 Physical Dimensions:5.1.1 Dimensional requirements shall be in accordance withapplicable drawings and purchase order documents.5.1.2 Pellet dimensions shall be measured to ensure com-pliance with the buyers requirements.5.2 Density:5.2.1 Pellet density limits shall be specified by the buye
11、r.5.2.2 The method of density measurement shall be TestMethod C 559 or an alternative method approved by the buyer.Sampling plans to meet the acceptance criteria shall be agreedupon between the buyer and the seller. The method of densitymeasurement and the method of compliance with 5.2.1 shall beapp
12、roved by the buyer.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 Specifications.Current edition approved Feb. 15, 2007. Published April 2007. Originallyapproved in 1975. Di
13、scontinued in April 2001 and reinstated as C75107. Lastprevious edition approved in 1992 as C 751 92.2For 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 D
14、ocument Summary page onthe ASTM website.3Withdrawn.4Available from American National Standards Institute, 11 W. 42nd St., 13thFloor, New York, NY 10036.5Available from U.S. Government Printing Office, Washington, DC 20402.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Consho
15、hocken, PA 19428-2959, United States.5.3 Visual AppearanceVisual examination shall be con-ducted on finished pellets in accordance with Section 7 onSampling. As soon as practical after finished pellets areavailable, the seller and buyer shall jointly select two sets ofvisual standards for defining t
16、he requirements of 5.3.1, 5.3.2,and 5.3.3. One set of standards shall be used each by the sellerand buyer as an acceptance standard in the visual examinationof the pellets. The method of measurement of defects in case ofa dispute shall be approved by the buyer. Maximum permis-sible defects are defin
17、ed as follows:5.3.1 End ChipsPellet end surfaces shall not be chippedbeyond 10 % of the end-face surface area, and no chip shallexceed 1.02 mm (0.040 in.) in depth.5.3.2 Circumferential ChipsPellet circumferential sur-faces shall not be chipped beyond 5 % of the circumferentialsurface area. No singl
18、e chip shall exceed a depth of 1.02 mm(0.040 in.).5.3.3 CracksIndividual cracks not exceeding 90 of cir-cumference in length are acceptable provided other require-ments of the specification are met. Acceptable number ofcracks shall be specified by the buyer5.3.4 Fissures and other defects shall be e
19、valuated withrespect to the criteria of 5.3.1, 5.3.2, and 5.3.3.5.4 Mechanical PropertiesRequired mechanical proper-ties and test methods shall be mutually agreed upon betweenbuyer and seller.6. Cleanliness6.1 finished pellets shall be handled in a manner to avoidcontamination by grinding fluids and
20、 dust, agents and organicmaterials such as plastics and paper used in packaging.Cleaning solutions, if used, shall be free of halides or nonvola-tile additives and shall be removed from the pellets prior tosampling and packaging.7. Sampling7.1 Sampling plans to meet acceptance criteria and inspec-ti
21、on and measurement procedures that describe the method ofcompliance with this specification shall be approved by thebuyer prior to manufacture of the required pellets. The degreeof sampling varies with the application and for this reasonshould be specified in the purchase order. E 105 is referenceda
22、s a guide.7.2 Powder and pellet samples taken shall be sufficient, asnecessary, for quality verification tests, acceptance tests, ref-eree tests, and the retention of archive samples7.3 Archive samples shall be retained and disposed of inaccordance with the buyers instructions.8. Inspection and Cert
23、ification8.1 The seller shall inspect the material covered by thisspecification and shall furnish the buyer with certificates oftests showing the results of testing and inspection performed oneach pellet lot prior to shipment. The seller shall certify thateach pellet lot is in compliance with the pr
24、ovisions of thisspecification.9. Rejection and Rehearing9.1 Unless buyer and seller agree otherwise, rejection andacceptance 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 seller maypetition the buyer to
25、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 he can demonstrate tothe buyer that such remedy does not impair the function orpreclude the
26、certification of the rejected material.9.3 In the event of disagreement over the results of analyses,samples shall be submitted to a mutually selected referee forresolution.10. Packaging and Shipping10.1 The pellets shall be packaged in sealed containers forshipment from the seller to the buyer. The
27、 seller shall beresponsible for using the shipping container to ensure thepellets arrive still in conformance with this specification.10.2 Each container shall be clearly marked with the fol-lowing: Boron carbide pellets, purchase order number, gross,net, and tare weights, lot number, and name of se
28、ller.11. Quality Assurance11.1 Quality assurance requirements shall be agreed uponbetween the buyer and seller when specified in the purchaseorder. Code of Federal Regulations Title 10 Part 50 AppendixB and ASTME NQA-1 are referenced as guides.12. Keywords12.1 boron carbide pellets; B4C neutron abso
29、rber; controlmaterialTABLE 1 1 Chemical Analysis of Finished Boron Carbide PelletsConstituent LimitsTotal boron 81.0 % weight, max73.0 % weight, minNitric acid-soluble boron 0.5 % weight, maxWater-soluble boron 0.2 % weight, maxCalcium 0.3 % weight, maxIron 1.0 % weight, maxTotal boron + total carbo
30、n 98.0 % weight, minFluoride 25 g/g, maxChloride 75 g/g, maxWater 750 g/g, maxAAUltimate usage of the pellets in a control rod may require drying to a lowermoisture level.C751072ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item men
31、tionedin 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 committee
32、 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 a meetin
33、g 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 Drive, PO
34、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).C751073
