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 ther
2、efrom, 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 2017 SAE International All rights reserved. No part of this
3、publication 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: +1 724-776-49
4、70 (outside USA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SAE values your input. To provide feedback on this Technical Report, please visit http:/standards.sae.org/AMS4251B AEROSPACE MATERIAL SPECIFICATION AMS4251 REV. B Issued 1989-04 Reaffirmed 2011-11 Rev
5、ised 2017-09 Superseding AMS4251A Aluminum Alloy Sheet 2.7Cu - 2.2Li - 0.12Zr (2090-T83) Solution Heat Treated, Cold Worked, and Precipitation Heat Treated (Composition similar to UNS A92090) RATIONALE AMS4251B revises Condition (3.2), Properties (3.3.2), Acceptance Tests (4.2.1), Reports (4.4), and
6、 Identification (5.1.1), and is a Five-Year Review and update of this specification. 1. SCOPE 1.1 Form This specification covers an aluminum alloy in the form of sheet 0.040 to 0.249 inch (1.02 to 6.32 mm) in thickness (see 8.6). 1.2 Application Primarily for applications requiring the strength of A
7、MS4045 and 7.8% lower nominal density. 2. APPLICABLE DOCUMENTS The 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 i
8、ssue 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 Publications Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (insid
9、e USA and Canada) or +1 724-776-4970 (outside USA), www.sae.org. AMS2355 Quality Assurance, Sampling and Testing Aluminum Alloys and Magnesium Alloy Wrought Products (Except Forging Stock), and Rolled, Forged, or Flash Welded Rings AMS2772 Heat Treatment of Aluminum Alloy Raw Materials ARP1917 Clari
10、fication of Terms Used in Aerospace Metals Specifications SAE INTERNATIONAL AMS4251B Page 2 of 5 2.2 ANSI Publications Copies of these documents are available online at http:/webstore.ansi.org/. ANSI H35.1/ H35.1M Standard Alloy and Temper Designation System For Aluminum ANSI H35.2 Dimensional Toler
11、ances for Aluminum Mill Products ANSI H35.2M Dimensional Tolerances for Aluminum Mill Products (Metric) 2.3 ASTM Publications: Available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, www.astm.org. ASTM B660 Packaging/Packing of Al
12、uminum and Magnesium Products ASTM B666 Identification and Marking of Aluminum and Magnesium Products ASTM G34 Exfoliation Corrosion Susceptibility in 2XXX and 7XXX Series Aluminum Alloys (EXCO Test) ASTM G85 Modified Salt Spray (Fog) Testing ASTM G112 Conducting Exfoliation Corrosion Tests in Alumi
13、num Alloys 3. TECHNICAL REQUIREMENTS 3.1 Composition Shall conform to the following percentages by weight shown in Table 1, determined in accordance with AMS2355. Table 1 Composition Element Min Max Silicon - 0.10 Iron - 0.12 Copper 2.4 3.0 Manganese - 0.05 Magnesium - 0.25 Chromium - 0.05 Zinc - 0.
14、10 Titanium - 0.15 Lithium 1.9 2.6 Zirconium 0.08 0.15 Other Elements, each - 0.05 Other Elements, total - 0.15 Aluminum remainder 3.2 Condition Solution heat treated, cold worked, and precipitation heat treated to the T83 temper, see ANSI H35.1/H35.1M. 3.2.1 Heat treatment shall be in accordance wi
15、th AMS2772; times and temperatures shall be established by the producer (see 8.4). SAE INTERNATIONAL AMS4251B Page 3 of 5 3.3 Properties Shall conform to the following requirements, determined in accordance with AMS2355 on the mill produced size: 3.3.1 Tensile Properties Shall be as specified in Tab
16、le 2. Table 2 Table 2A Nominal Thickness Inches Specimen Orientation Tensile Strength ksi, min Yield Strength at 0.2% Offset ksi, minimum Elongation in 2 Inches %, minimum 0.040 to 0.125, incl Longitudinal Long-Transverse 77.0 73.0 70.0 66.0 3 5 Over 0.125 to 0.249, incl Longitudinal Long-Transverse
17、 75.0 73.0 70.0 66.0 4 5 Table 2B (SI) Nominal Thickness Millimeters Specimen Orientation Tensile Strength MPa, min Yield Strength at 0.2% Offset MPa, minimum Elongation in 50.8 mm %, minimum 1.02 to 3.18, incl Longitudinal Long-Transverse 531 503 483 455 3 5 Over 3.18 to 6.32, incl Longitudinal Lon
18、g-Transverse 517 503 483 455 4 5 3.3.1.1 Tensile property requirements for sheet under 0.040 inch (1.02 mm) in nominal thickness shall be as agreed upon by purchaser and producer. 3.3.2 Exfoliation-Corrosion Resistance Sheet shall not exhibit exfoliation corrosion greater than that illustrated by Ph
19、otograph EB, Figure 2, of ASTM G34 when specimens are exposed for 2 weeks according to the procedures in ASTM G85 Annex A2, using the dry-bottom MASTMAASIS Test Method (see 8.5). 3.4 Quality Sheet, as received by purchaser, shall be uniform in quality and condition, sound, and free from foreign mate
20、rials and from imperfections detrimental to usage of the sheet. 3.5 Tolerances Shall conform to all applicable requirements of ANSI H35.2 or ANSI H35.2M. SAE INTERNATIONAL AMS4251B Page 4 of 5 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for Inspection The producer of sheet shall supply all sa
21、mples for producers tests and shall be responsible 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 sheet conforms to specified requirements. 4.2 Classification of Tests 4.2.1 Acceptance Test
22、s: Composition (3.1), long- transverse tensile properties (3.3.1), tolerances (3.5), and, when specified, longitudinal tensile properties (3.3.1) are acceptance tests and, except for composition, shall be performed on each lot. 4.2.2 Periodic Tests Exfoliation-corrosion resistance (3.3.2) is a perio
23、dic test and shall be performed at a frequency selected by the producer unless frequency of testing is specified by purchaser. 4.3 Sampling Shall be in accordance with AMS2355. 4.4 Reports 4.4.1 The producer of sheet shall furnish with each shipment a report stating that the sheet conforms to the co
24、mposition, showing the results of tests on each inspection lot to determine conformance to the other acceptance test requirements, and stating that the sheet conforms to the other technical requirements of this specification. This report shall include the purchase order number, inspection lot number
25、, AMS4251B, size, quantity. The report shall also identify the producer, the product form, and the mill produced size. 4.4.2 When the product size is outside the range covered by 1.1, the report shall contain a statement to that effect. 4.4.3 When material produced to this specification is beyond th
26、e sizes allowed in the scope of tables, or other exceptions are taken to the technical requirements listed in Section 3 (see 5.1.1), the report shall contain a statement “This material is certified as AMS4251B(EXC) because of the following exceptions.” and the specific exceptions shall be listed. 4.
27、5 Resampling and Retesting Shall be in accordance with AMS2355. 5. PREPARATION FOR DELIVERY 5.1 Identification Shall be in accordance with ASTM B666/B666M. 5.1.1 When technical exceptions are taken (see 4.4.2), the material shall be marked with AMS4251(EXC). 5.2 Protective Treatment Product shall be
28、 protected from damage during storage and shipment by a method determined by the producer, unless specified by purchaser. Examples of typical protective coating include but are not limited to interleaving with paper or oiling of the surface. SAE INTERNATIONAL AMS4251B Page 5 of 5 5.3 Packaging The p
29、roduct shall be prepared for shipment in accordance with ASTM B660 and in compliance with applicable rules and regulations pertaining to the handling, packaging, and transportation of the product to ensure carrier acceptance and safe delivery. 6. ACKNOWLEDGMENT A producer shall mention this specific
30、ation number and its revision letter in all quotations and when acknowledging purchaser orders. 7. REJECTIONS Sheet not conforming to this specification, or to modifications authorized by purchaser, will be subject to rejection. 8. NOTES 8.1 Revision Indicator A change bar (I) located in the left ma
31、rgin is for the convenience of the user in locating areas where technical revisions, not editorial changes, have been made to the previous issue 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
32、 and (R) are not used in original publications, nor in documents that contain editorial changes only. 8.2 Terms used in AMS are clarified in ARP1917. 8.3 Dimensions and properties in inch/pound units and the Fahrenheit temperatures are primary; dimensions and properties in SI units and the Celsius t
33、emperatures are shown as the approximate equivalents of the primary units and are presented only for information. 8.4 Heat treatment and cold working parameters are proprietary. 8.5 The solution used for exposure by ASTM G34, the EXCO Test, has been determined to be inappropriate for Al-Li alloys. F
34、or further information on this, review ASTM G112 which describes limitations on this test method for Al-Li alloys. 8.6 Purchase documents should specify not less than the following: AMS4251B Size of sheet desired Longitudinal tensile properties (if required) (see 3.3.1) Property and acceptance requirements from the cognizant engineering organization applicable to sizes outside the range listed in 1.1 Quantity of sheet desired PREPARED BY AMS COMMITTEE “D“
