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 isentirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefr
2、om, 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 2015 SAE InternationalAll rights reserved. No part of this public
3、ation 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 (outs
4、ide 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/AMS7718HAEROSPACEMATERIAL SPECIFICATIONAMS7718 REV. HIssued 1981-01Revised 2015-08Superseding
5、AMS7718GNickel-Iron Alloy, Magnetic, Bars, Rods, Tubing, and Forgings50Ni - 50Fe(Composition similar to UNS K95000)RATIONALEAMS7718H results from a Five Year Review and update of this specification. 1. SCOPE1.1 FormThis specification covers a magnetically soft nickel-iron alloy in the form of bars,
6、rods, forgings, mechanical tubing, and forging stock.1.2 ApplicationThese products have been used typically for parts in magnetic circuits requiring high magnetic permeability and high saturation induction with the fabricated parts to be annealed in dry hydrogen, but usage is not limited to such app
7、lications.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 herein. The supplier may work to a subsequent revision of a document unless a specific document issue is specified. When the re
8、ferenced document has been cancelled and no superseding document has been specified, the last published issue of that document shall apply.2.1 SAE PublicationsAvailable from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or +1 724-776-
9、4970 (outside USA), www.sae.org.AMS2241 Tolerances, Corrosion and Heat-Resistant Steel, Iron Alloy, Titanium, and Titanium Alloy Bars and WireAMS2243 Tolerances, Corrosion and Heat-Resistant Steel TubingAMS2371 Quality Assurance Sampling and Testing, Corrosion and Heat-Resistant Steels and Alloys, W
10、rought Products and Forging StockAMS2374 Quality Assurance Sampling and Testing, Corrosion and Heat-Resistant Steel and Alloys ForgingsSAE INTERNATIONAL AMS7718H Page 2 of 5AMS2806 Identification Bars, Wire, Mechanical Tubing, and Extrusions, Carbon and Alloy Steels and Corrosion and Heat-Resistant
11、Steels and AlloysAMS2808 Identification Forgings2.2 ASTM PublicationsAvailable from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, www.astm.org.ASTM A596/A596M Direct-Current Magnetic Properties of Materials Using the Ballistic Method a
12、nd Ring SpecimensASTM A773/A773M D-C Magnetic Properties of Materials Using Ring and Permeameter Procedures with dc Electronic Hysteresigraphs.ASTM E18 Rockwell Hardness of Metallic Materials3. TECHNICAL REQUIREMENTS3.1 CompositionShall be an alloy containing approximately 50% nickel and 50% iron wi
13、th other alloying elements in such proportions as required to provide a product meeting the requirements of 3.3.3.2 ConditionThe product shall be supplied in the following condition:3.2.1 Bars, Rods, and Mechanical TubingCold drawn, partially annealed (See 8.2), and centerless ground.3.2.2 ForgingsA
14、s ordered.3.2.3 Forging StockAs ordered by the forging manufacturer.3.3 PropertiesThe product shall conform to the following requirements:3.3.1 HardnessShall be as follows, determined in accordance with ASTM E18.3.3.1.1 Bars and forgings 0.50 inch (12.7 mm) and under in nominal diameter or cross-sec
15、tional thickness and mechanical tubing shall have hardness not higher than 100 HRB, or equivalent (See 8.3).3.3.1.2 Bars and forgings over 0.50 to 2.00 inches (12.7 to 50.8 mm) in nominal diameter or cross-sectional thickness shall have hardness not higher than 90 HRB, or equivalent (See 8.3).SAE IN
16、TERNATIONAL AMS7718H Page 3 of 53.3.2 Magnetic PropertiesShall be as shown in Table 1, determined in accordance with ASTM A596/A596M or ASTM A773/A773M on specimens as in 4.3.3 annealed by heating to 2150 F 25 (1177 C 14) in a dry hydrogen atmosphere having a dew point of -60 F (-51 C) or lower, hol
17、ding at heat for 4 hours 0.25, and cooling in a non-contaminating atmosphere at a rate not greater than 100 F (56 C) degrees per hour to 800 F (427 C) or lower, unless another cooling rate is recommended by the alloy producer (See 8.2). The annealed maximum coercive force (Hc) from 10 000 Gauss, (1.
18、0 T) shall be 0.070 Oersted (5.57 A/m).Table 1 - Annealed minimum magnetic propertiesNominal Diameter orLeast DistanceBetween Parallel SidesInchNominal Diameter orLeast DistanceBetween ParallelSidesMillimetersMaximumPermeabilityPermeability atB = 100 Gauss(0.01T)Induction atH = 100 Oersteds(7958 A/m
19、)Up to 5/16, excl Up to 7.9, excl 50 000 6000 15 000 gauss (1.5T)5/16 and over 7.9 and over 50 000 4000 15 000 gauss (1.5T)3.4 QualityThe product, as received by purchaser, shall be uniform in quality and condition, sound, and free from foreign materials and from imperfections detrimental to usage o
20、f the product.3.5 TolerancesShall be as follows:3.5.1 Bars and RodsIn accordance with AMS2241.3.5.2 Mechanical TubingIn accordance with AMS2243.4. QUALITY ASSURANCE PROVISIONS4.1 Responsibility for InspectionThe producer of the product shall supply all samples for producers tests and shall be respon
21、sible for the performance of all required tests. Purchaser reserves the right to sample and to perform any confirmatory testing deemed necessary to ensure that the product conforms to specified requirements.4.2 Classification of TestsAll technical requirements are acceptance tests and shall be perfo
22、rmed on each heat or lot.4.3 Sampling and Testing4.3.1 Bars, Rods, Mechanical Tubing, and Forging StockIn accordance with AMS2371.SAE INTERNATIONAL AMS7718H Page 4 of 54.3.2 ForgingsIn accordance with AMS2374.4.3.3 For magnetic property tests, one or more samples shall be selected at random from eac
23、h lot.4.4 ReportsThe producer of the product shall furnish with each shipment a report showing the producer identity, the results of tests for hardness and magnetic properties of each lot, and stating that the product conforms to the other technical requirements. This report shall include the purcha
24、se order number, heat and lot numbers, AMS7718H, cooling rate if other than 100 F (56 C) degrees per hour, test method used for magnetic properties testing, product form, size, and quantity. If forgings aresupplied, the size and melt source of stock used to make the forgings shall also be included.4
25、.5 Resampling and Retesting4.5.1 Bars, Rods, Mechanical Tubing, and Forging StockIn accordance with AMS2371.4.5.2 ForgingsIn accordance with AMS2374.5. PREPARATION FOR DELIVERY5.1 SizesExcept when exact lengths or multiples of exact lengths are ordered, straight bars, rods, and tubing will be accept
26、able in mill lengths of 6 to 20 feet (1.8 to 6.1 m) but not more than 10% of any shipment shall be supplied in lengths shorter than 10 feet (3 m).5.2 Identification5.2.1 Bars, Rods, and Mechanical TubingIn accordance with AMS2806.5.2.2 ForgingsIn accordance with AMS2808.5.2.3 Forging StockAs agreed
27、upon by purchaser and producer.5.3 Protective TreatmentProduct shall be protected from corrosion prior to shipment.5.4 PackagingThe product shall be prepared for shipment in accordance with commercial practice and in compliance with applicable rules and regulations pertaining to the handling, packag
28、ing, and transportation of the product to ensure carrier acceptance and safe delivery.SAE INTERNATIONAL AMS7718H Page 5 of 56. ACKNOWLEDGMENTA producer shall include this specification number and its revision letter in all quotations and when acknowledging purchase orders.7. REJECTIONSProduct not co
29、nforming to this specification, or to modifications authorized by purchaser, will be subject to rejection.8. NOTES8.1 A change bar (l) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial changes, have been made to the previous issu
30、e of this document. An (R) symbol to the left of the document title indicates a complete revision of the document, including technical revisions. Change bars and (R) are not used in original publications, nor in documents that contain editorial changes only.8.2 Annealing of fabricated parts is requi
31、red to produce the required magnetic properties. Dry hydrogen atmosphere is typically recommended. Vacuum or other protective atmospheres may produce magnetic properties that are not equivalent to those produced in dry hydrogen.8.3 Hardness conversion tables for metals are presented in ASTM E140.8.4
32、 Terms used in AMS are clarified in ARP1917.8.5 Dimensions and properties in inch/pound units and the Fahrenheit temperatures are primary; dimensions and properties in SI units and the Celsius temperatures are shown as the approximate equivalents of the primary units and are presented only for information.8.6 Purchase documents should specify not less than the following:AMS7718HProduct form and size or part number of product desiredQuantity of product desired.PREPARED BY AMS COMMITTEE “E“
