1、_SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising theref
2、rom, is the sole responsibility of the user.”SAE reviews each technical report at least every five years at which time it may be revised, reaffirmed, stabilized, or cancelled. SAE invites your written comments and suggestions.Copyright 2013 SAE InternationalAll rights reserved. No part of this publi
3、cation may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE.TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada)Tel: +1 724-776-4970 (out
4、side USA)Fax: 724-776-0790Email: CustomerServicesae.orgSAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedbackon this Technical Report, please visithttp:/www.sae.org/technical/standards/AMS7881AAEROSPACE MATERIAL SPECIFICATIONAMS7881 REV. AIssued 2003-04Revised 2007-06Reaffirmed
5、 2013-07Superseding AMS7881Tungsten Carbide-Cobalt PowderAgglomerated and SinteredRATIONALEAMS7881A has been reaffirmed to comply with the SAE five-year review policy.1. SCOPE1.1 FormThis specification covers tungsten carbide-cobalt in the form of powder.1.2 ApplicationThis powder has been used typi
6、cally for producing thermal spray coatings to provide wear and fretting resistant surfaces, but usage is not limited to such applications.2. APPLICABLE DOCUMENTSThe issue of the following documents in effect on the date of the purchase order forms a part of this specification to the extent specified
7、 herein. The supplier may work to a subsequent revision of a document unless a specific document issue is specified. When the referenced document has been cancelled and no superseding document has been specified, the last published issue of that document shall apply.2.1 SAE PublicationsAvailable fro
8、m SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org.AMS 2448 Application of Tungsten Carbide Coatings on Ultrahigh Strength Steels, High Velocity Oxygen/Fuel Process2.2 ASTM PublicationsAvailable
9、 from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959,Tel: 610-832-9585, www.astm.org.ASTM B 215 Sampling Finished Lots of Metal PowdersASTM B 822 Particle Size Distribution of Metal Powders and Related Compounds by Light ScatteringASTM Manual 32 Manual on
10、Test Sieving MethodsSAE INTERNATIONAL AMS7881A Page 2 of 53. TECHNICAL REQUIREMENTS3.1 Composition shall conform to the percentages by weight shown in Table 1, determined by methods acceptable to the cognizant engineering organization.TABLE 1 - COMPOSITIONPercent by WeightElement min maxCobalt 15.0
11、18.5Carbon, Total 4.8 5.6Tungsten BalanceIron - 1.5Others (if determined) - 0.53.2 Condition shall be as manufactured.3.3 PropertiesPowder shall conform to the following requirements:3.3.1 Particle size distribution shall be as shown in Tables 2 and 3. Each lot shall show the following cumulative Ta
12、ble 2 volume percentages when measured by laser light scattering method in accordance with ASTM B 822 or other method acceptable to the cognizant engineering organization. See 8.2. Each lot shall have the cumulative Table 3 weight percentages using ASTM Manual 32 as a guide or other method acceptabl
13、e to the cognizant engineering organization. Measured distribution percentages can vary by application method. See 8.3.TABLE 2 - PARTICLE SIZE DISTRIBUTIONPercent by Volume, Method 1Micron Size Minimum % Maximum %+62 - 10+44 18 35+22 60 95+11 92 -Percent by Volume, Method 2Micron Size Minimum % Maxi
14、mum %+62 - 5+44 10 30+22 75 95+11 98 -Percent by Volume, Method 3Micron Size Minimum % Maximum %+62 - 15+44 25 45+22 80 95+11 95 -SAE INTERNATIONAL AMS7881A Page 3 of 5TABLE 3 - PARTICLE SIZE DISTRIBUTION BY SIEVE SIZEPercent by Weight, Method 1Sieve Size Minimum % Maximum %+270 - 6%+325 - 25%Percen
15、t by Weight, Method 2Sieve Size Minimum % Maximum %+270 - 5%+325 - 25%Percent by Weight, Method 3Sieve Size Minimum % Maximum %+270 - 5%+325 - 15%3.3.2 Thermal spray powder shall be capable of producing thermal spray coatings that meet the requirements of AMS 2448 or alternative requirements accepta
16、ble to the cognizant engineering organization.3.4 QualityPowder, as received by purchaser, shall be thoroughly blended, uniform in color and quality, dry, free flowing and free from foreign materials, clumps and imperfections detrimental to its spraying qualities.4. QUALITY ASSURANCE PROVISIONS4.1 R
17、esponsibility for InspectionThe supplier of powder shall provide all samples for suppliers tests and shall be responsible for the performance of all required tests. The cognizant engineering organization reserves the right to sample and to perform any confirmatory testing deemed necessary to ensure
18、that the powder conforms to specified requirements.4.2 Classification of TestsTests for all technical requirements are acceptance tests and preproduction tests and shall be performed prior to or on the initial shipment of powder to a purchaser, on each lot, when a change in ingredients and/or proces
19、sing requires approval by the cognizant engineering organization (4.4.2), and when the cognizant engineering organization deems confirmatory testing to be required.4.3 Sampling and testing shall be in accordance with ASTM B 215 or alternative in accordance with 4.3.1. Sufficient powder shall be take
20、n from each lot to perform all required tests. The number of determinations for each requirement shall be as specified in the applicable test procedure or, if not specified therein, not less than three.4.3.1 The cognizant engineering organization and supplier may agree upon an alternative statistica
21、l sampling plan.4.4 Approval4.4.1 The process and control procedures, a preproduction sample, or both, whichever is specified, shall be approved by the cognizant engineering organization before production powder is supplied.4.4.2 If the supplier makes a significant change to any ingredient, process,
22、 or control from that which was used for approval, all tests shall be performed and the results submitted to the cognizant engineering organization for reapproval. A significant change is one, which, in the judgment of the cognizant engineering organization, could affect the properties or performanc
23、e of the powder.SAE INTERNATIONAL AMS7881A Page 4 of 54.5 ReportsThe supplier of a powder shall furnish with each shipment a report showing the results of tests for composition and particle size distribution of each lot and stating that the powder conforms to other technical requirements. The report
24、 shall include the purchase order number, lot number, AMS 7881A, suppliers product designation, quantity and the details of any alternative sampling plan established in accordance with 4.3.1.4.6 Resampling and RetestingIf any sample used in the above tests fails to meet the specified requirements, d
25、isposition of the powder may be based on the results of testing three additional samples for each original nonconforming sample. Failure of any retest sample to meet the specified requirements shall be cause for rejection of the powder represented. Results of all tests shall be reported.5. PREPARATI
26、ON FOR DELIVERY5.1 Packaging and Identification5.1.1 Powder shall be packaged in sealed containers to protect it from contamination during shipment and under normal dry storage conditions. Seals used on containers shall be so designed that they must be destroyed in order for the container to be open
27、ed.5.1.2 Each individual container shall be legibly identified with not less than the following information, using characters that will not be obliterated by normal handling:TUNGSTEN CARBIDE-COBALT CHROME POWDERAMS 7881AMANUFACTURERS IDENTIFICATIONPURCHASE ORDER NUMBERQUANTITYLOT NUMBER5.1.3 Contain
28、ers of powder shall be prepared for shipment in accordance with commercial practice and in compliance with applicable rules and regulations pertaining to the handling, packaging, and transportation of the powder to ensure carrier handling and safe delivery.6. ACKNOWLEDGMENTA supplier shall mention A
29、MS 7881A in all quotations and when acknowledging purchase orders.7. REJECTIONSPowder not conforming to this specification, or to modifications authorized by the cognizant engineering organization, will be subject to rejection.8. NOTES8.1 A change bar (|) located in the left margin is for the conven
30、ience of the user in locating areas where technical revisions, not editorial changes, have been made to the previous issue of a specification. An (R) symbol to the left of the document title indicates a complete revision of the specification, including technical revision. Change bars and (R) are not
31、 used in original publications, nor in specifications that contain editorial changes only.8.2 Microtrac AnalysisA specific method of particle parameter determination using low angle forward and/or 90 light scattering (Fraunhoffer Diffraction) and associated instrumentation, data reduction hardware a
32、nd software.SAE INTERNATIONAL AMS7881A Page 5 of 58.3 Method 1 designates powder materials typically sprayed with a SulzerMetco Diamond Jet HVOF thermal spray system. Method 2 designates powder materials typically sprayed with a Praxair/Tafa HVOF thermal spray system.Method 3 designates powder mater
33、ials typically sprayed with a Deloro Stellite Jet Kote HVOF thermal spray system.8.4 Terms used in AMS are clarified in ARP1917.8.5 Dimensions and properties in inch/pound units and Fahrenheit temperatures are primary; dimensions and properties in SI units and Celsius temperatures are shown as the a
34、pproximate equivalents of the primary units and are presented only for information.8.6 Purchase documents should specify not less than the following:AMS 7881AQuantity of powder desiredAlternative thermal spray acceptance requirements and sampling plan, as applicable See 3.3.2 and 4.3.1.PREPARED BY AMS COMMITTEE “B”
