1、Designation: C784 05 (Reapproved 2012)C784 16Standard Specification forNuclear-Grade Aluminum Oxide-Boron Carbide CompositePellets1This standard is issued under the fixed designation C784; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revi
2、sion, the year of last revision. A number in 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 composed of mixtures of aluminum oxide and boron carbide that
3、may be ultimately usedin a reactor core, for example, in neutron absorber rods.1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.2. Referenced Documents2.1 ASTM Standards:2C559 Test Method for Bulk Density by Physical Measu
4、rements of Manufactured Carbon and Graphite ArticlesC750 Specification for Nuclear-Grade Boron Carbide PowderC809 Test Methods for Chemical, Mass Spectrometric, and Spectrochemical Analysis of Nuclear-Grade Aluminum Oxide andAluminumOxide-Boron Carbide Composite PelletsC859 Terminology Relating to N
5、uclear MaterialsC1031 Specification for Nuclear-Grade Aluminum Oxide PowderE11 Specification for Woven Wire Test Sieve Cloth and Test SievesE105 Practice for Probability Sampling of Materials2.2 ANSI Standard:ANSI/ASME NQA-1 Quality Assurance Program Requirements for Nuclear Facilities32.3 Governmen
6、t Standard:Title 10, Code of Federal Regulations, Energy Part 50 (10CFR50), Domestic Licensing of Production and Utilization Facilities43. Terminology3.1 Definitions:3.1.1 Terms shall be defined in accordance with Terminology C859 except for the following:3.2 Definitions of Terms Specific to This St
7、andard:3.2.1 buyerorganization issuing the purchase order.3.2.2 pelleta fabricated geometric shape of aluminum oxide-boron carbide having a chemical composition as described inSection 4.3.2.3 pellet lotthat quantity of pellets produced from one powder mixture lot using one set of mixing and process
8、parameters.Pellet lot size shall be agreed upon between the seller and the buyer.3.2.4 powder mixture lota specified quantity of aluminum oxide and boron carbide made up of powders from one or moresources blended together such that samples taken in accordance with Section 7 can be considered as repr
9、esentative of the entirespecified quantity.3.2.5 sellerpellet supplier.1 This specification is under the jurisdiction ofASTM Committee C26 on Nuclear Fuel Cycle and is the direct responsibility of Subcommittee C26.03 on NeutronAbsorberMaterials Specifications.Current edition approved Jan. 1, 2012Apr
10、il 1, 2016. Published January 2012April 2016. Originally approved in 1976. Last previous edition approved in 20052012 asC784 05.C784 05 (2012). DOI: 10.1520/C0784-05R12.10.1520/C0784-16.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceast
11、m.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from American National Standards Institute, 11 W. 42nd St., 13th Floor, New York, NY 10036.4 Available from Superintendent of Documents, U.S. Government Printing O
12、ffice, Washington, DC 20402.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends
13、that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Technical Require
14、ments4.1 Major ConstituentsAluminum oxide-boron carbide pellets shall be fabricated using major constituents that meet therequirements of Specifications C750 and C1031.4.2 Chemical Composition:4.2.1 Use analytical chemistry methods in accordance with Methods C809 or demonstrated alternate methods ag
15、reed uponbetween the buyer and the seller.4.2.2 The finished pellets shall conform to the following chemical analysis:C784 162Si 2.0 weight % maxFe + Cr + Ni 0.6 weight % maxMg 1.0 weight % maxNa 0.2 weight % maxsCa 0.3 weight % maxHf 200 g/g pellet maxF 50 g/g pellet maxF + Cl + I + Br 100 g/g pell
16、et maxGd 25 g/g pellet maxSm 50 g/g pellet maxEu 50 g/g pellet maxDy 50 g/g pellet maxElement Weight %, maxSilicon (Si) 2.0Iron + Chromium + Nickel(Fe + Cr + Ni)0.6Magnesium (Mg) 1.0Sodium (Na) 0.2Calcium (Ca) 0.3Hafnium (Hf) 200 g/g pelletFluorine (F) 50 g/g pelletFluorine + Chlorine + Iodine + Bro
17、mine(F + Cl + I + Br)100 g/g pelletGadolinium (Gd) 25 g/g pelletSamarium (Sm) 50 g/g pelletEuropium (Eu) 50 g/g pelletDysprosium (Dy) 50 g/g pelletAny elemental impurity not listed in 4.2.2 shall not exceed 1 weight % as determined by emission spectroscopy. spectroscopyor method agreed upon between
18、buyer and seller. The sum of all impurities shall not exceed 4.0 weight %. A water-soluble boronlimit may be required in certain designs in which case it shall be determined on a sample crushed to pass through a No. 100 mesh(150-m) U.S. standard sieve (see Specification E11.)4.2.3 Should elements no
19、t listed in 4.2.2 be of concern, their inclusion in the listing shall be mutually agreed upon between thebuyer and the seller.4.2.4 In specifying the allowable range in 10B concentration the buyer shall consider the following:4.2.4.1 Variations in chemical composition,4.2.4.2 Bulk pellet density,4.2
20、.4.3 Boron isotopic composition,4.2.4.4 Pellet dimensions, and4.2.4.5 Typical units are grams of 10B per unit volume or grams of 10B per centimeter length.4.2.5 The hydrogen impurity (including moisture content), the detailed procedure for measuring hydrogen, and packagingrequirements associated wit
21、h hydrogen contamination, shall be agreed upon between the buyer and the seller.5. Physical Requirements5.1 Physical Dimensions:5.1.1 Dimensional requirements shall be in accordance with applicable drawings and purchase order documents.5.1.2 Pellet dimensions shall be measured to ensure compliance w
22、ith the buyers requirements. Sampling plans to meetacceptance criteria shall be agreed upon between the seller and the buyer to ensure that the pellets represented by the sample arewithin the required tolerances.5.2 Density:5.2.1 Pellet density limits shall be specified by the buyer.5.2.2 The method
23、 of density measurement shall be Test Method C559 or an alternative method approved by the buyer prior touse. Sampling plans to meet acceptance criteria shall be agreed upon between the seller and the buyer.5.3 Boron Carbide Homogeneity:5.3.1 The boron carbide shall be uniformly dispersed in the alu
24、minum oxide matrix as determined by ceramographicexamination.5.3.2 The methods of ceramographic preparation and examination shall be approved by the buyer prior to use.5.3.3 Pellets selected by mutual agreement between the buyer and the seller shall be used as standards of acceptability to satisfyth
25、e requirements of 5.3.1. The seller shall submit as homogeneity standards, pellets representative of each specified boronconcentration (per 4.2.14.2.4).5.3.4 Particle size limits of boron carbide particles shall be specified by the buyer in accordance with his particular intendedapplication.5.4 Mech
26、anical PropertiesRequired mechanical properties and test methods shall be mutually agreed upon between the buyerand the seller.C784 1635.5 Visual AppearanceVisual examination shall be conducted on finished pellets in accordance with Section 7. The seller andthe buyer shall agree on visual standards
27、as representing the requirements of 5.5.1, 5.5.2, and 5.5.3. These standards shall be usedas acceptance standards for the visual examination of the pellets. The method of defect measurement shall be approved by thebuyer prior to use. Maximum permissible defects are defined as follows:5.5.1 End Chips
28、Pellet end surface shall not be chipped beyond 10 % of the end-face surface area and no chip shall exceed1.0 mm (0.040 in.) in depth.5.5.2 Circumferential ChipsPellet circumferential surfaces shall not be chipped beyond 5 % of the circumferential surfacearea. No single chip shall exceed a depth of 1
29、.0 mm (0.040 in.).5.5.3 CracksNo single crack shall exceed 90 of circumference in length.5.5.4 Fissures and other defects shall be evaluated with respect 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 to avoid contamination by grinding
30、fluids and dust, cleaning agents, andorganic materials such as plastics and paper used in packaging. Cleaning solutions, if used, shall be free of halides and nonvolatileadditives and shall be removed from the pellets prior to sampling and packaging.7. Sampling7.1 Sampling plans to meet acceptance c
31、riteria and inspection and measurement procedures that describe the method ofcompliance with this specification shall be established by the seller and submitted to the buyer for approval prior to manufactureof the required product. The degree of sampling shall be specified on the purchase order. Pra
32、ctice E105 is referenced as a guide.7.2 Each sample taken shall be sufficient for quality verification tests, referee tests and archive samples as needed.7.3 Archive samples shall be retained and disposed by the seller in accordance with the buyers instructions.8. Inspection and Certification8.1 The
33、 seller shall inspect the material covered by this specification and shall furnish the buyer with certificates of testsshowing the results of testing and inspection performed on each pellet lot prior to shipment. The seller shall certify that each pelletlot is in compliance with the provisions of th
34、is specification.9. Rejection9.1 Unless the buyer and the seller agree otherwise, rejection and acceptance shall be on a pellet lot basis.9.2 Pellet lots that fail to conform to the requirements of this specification may be rejected by the buyer. The seller may petitionthe buyer to waive selected re
35、quirements for identified out-of-specification lots. Decision to grant such waiver belongs to the buyer.The seller may also apply buyer shall approve, prior to use, any remedy proposed to bring rejected lots into specification providinghe can demonstrate to the buyer that such remedy does not impair
36、 the function or preclude the certification of the rejectedmaterial.specification.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 f
37、or shipment from the seller to the buyer. The seller shall be responsiblefor using the shipping container to assure the pellets arrive still in conformance with the specification, and to assure reasonableease of unpacking.10.2 Each container shall be clearly marked with the following:10.2.1 Aluminum
38、 oxide-boron carbide composite pellets,10.2.2 Purchase order number,10.2.3 Gross, net, and tare weights,10.2.4 Lot number, and10.2.5 Name of manufacturer.11. Quality Assurance11.1 Quality assurance requirements shall be specified in the purchase order. Code of Federal Regulations, Title 10, Part 50,
39、Appendix B, and ANSI/ASME NQA-1 are referenced as guides.C784 16412. Keywords12.1 absorber pellets; aluminum oxide; boron carbide; poison pelletsASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of
40、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 and must be reviewed every five
41、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 meeting of theresponsible technical comm
42、ittee, 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 Box C700, West Conshohocken, PA 19
43、428-2959,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). 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:/ 165
