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 there
2、from, 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 2016 SAE International All rights reserved. No part of this p
3、ublication 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: +1 724-776-497
4、0 (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:/www.sae.org/technical/standards/AMS6494B AEROSPACE MATERIAL SPECIFICATION AMS6494 REV. B Issued 2009-09 Revised 2
5、016-06Superseding AMS6494A Steel Bars, Forgings, and Tubing 1.0Cr 2.50Ni 2.0Mo 1.10Si (0.10 0.20C) Aircraft-Quality (Composition similar to UNS K51570)RATIONALE AMS6494B is a Five Year Review and update of this specification that revises macrostructure testing methods, grain size sampling, and repor
6、ting. 1. SCOPE 1.1 Form This specification covers an aircraft-quality, low-alloy steel in the form of bars, forgings, mechanical tubing, and forging stock. 1.2 Application These products have been used typically for carburized parts requiring high minimum core hardness with a narrow range, reduced d
7、istortion and subject to magnetic particle inspection standards, but usage is not limited to such applications. 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
8、 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 Publications Available from SAE International, 40
9、0 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or +1 724-776-4970 (outside USA), www.sae.org. AMS2251 Tolerances Low-Alloy Steel Bars AMS2253 Tolerances, Carbon and Alloy Steel Tubing AMS2259 Chemical Check Analysis Limits Wrought Low-Alloy and Carbon Stee
10、ls AMS2301 Steel Cleanliness, Aircraft Quality Magnetic Particle Inspection Procedure SAE INTERNATIONAL AMS6494B Page 2 of 7 AMS2370 Quality Assurance Sampling and Testing, Carbon and Low-Alloy Steel Wrought Products and Forging Stock AMS2372 Quality Assurance Sampling and Testing Carbon and Low-All
11、oy Steel Forgings AMS2806 Identification Bars, Wire, Mechanical Tubing, and Extrusions Carbon and Alloy Steels and Corrosion and Heat-Resistant Steels and Alloys AMS2808 Identification Forgings ARP1917 Clarification of Terms Used in Aerospace Metals Specifications AS1182 Standard Stock Removal Allow
12、ance Aircraft-Quality and Premium Aircraft-Quality Steel Bars and Mechanical Tubing 2.2 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 A370 Mechanical Testing of Steel Products ASTM E3
13、81 Macroetch Testing Steel Bars, Billets, Blooms and Forgings ASTM E112 Determining Average Grain Size ASTM E140 Hardness Conversion Tables for Metals ASTM E350 Chemical Analysis of Carbon Steel, Low-Alloy Steel, Silicon Electrical Steel,Ingot Iron, and Wrought Iron ASTM E384 Knoop and Vickers Hardn
14、ess of Materials 3. TECHNICAL REQUIREMENTS 3.1 Composition Shall conform to the following percentages by weight shown in Table 1, determined by wet chemical methods in accordance with ASTM E350, by spectrochemical methods, or by other analytical methods acceptable to purchaser. Table 1 - Composition
15、 Element min max Carbon 0.10 0.20 Manganese - 1.00 Silicon 0.90 1.30 Phosphorus - 0.020 Sulfur - 0.015 Chromium 0.80 1.20 Nickel 2.30 2.70 Molybdenum 1.70 2.20 Vanadium - 0.50 SAE INTERNATIONAL AMS6494B Page 3 of 7 3.1.1 Check Analysis Composition variations shall meet the applicable requirements of
16、 AMS2259. 3.2 Condition The product shall be supplied in the following condition; hardness and tensile strength shall be determined in accordance with ASTM A370: 3.2.1 Bars Bar shall not be cut from plate (also see 4.4.2). 3.2.1.1 Bars 0.500 inch (12.70 mm) and Under in Nominal Diameter or Least Dis
17、tance Between Parallel Sides Cold finished having tensile strength not higher than 138 ksi (950 MPa) or hardness not higher than 285 HB or equivalent (see 8.2). 3.2.1.2 Bars over 0.500 inch (12.70 mm) in Nominal Diameter or Least Distance Between Parallel Sides Hot finished and annealed, unless othe
18、rwise ordered, having hardness not higher than 285 HB or equivalent (see 8.2). Bars ordered cold finished may have hardness as high as 310 HB or equivalent (see 8.2). 3.2.2 Forgings As ordered. 3.2.3 Mechanical Tubing Cold finished, unless otherwise ordered, having hardness not higher than 285 HB, o
19、r equivalent (see 8.2). Tubing ordered hot finished and annealed or tempered shall have hardness not higher than 285 HB or equivalent (see 8.2). 3.2.4 Forging Stock As ordered by the forging manufacturer. 3.3 Properties The product shall conform to the following requirements; hardness, tensile, and
20、impact testing shall be performed in accordance with ASTM A370: 3.3.1 Macrostructure Visual examination of transverse full cross-sections from bars, billets tube rounds, and forging stock, etched in hot hydrochloric acid in accordance with ASTM E381, shall show no pipe or cracks. Porosity, segregati
21、on, inclusions, and other imperfections shall be no worse than the macrographs of ASTM E381 shown in Table 2. Table 2 - Macrostructure limits Cross-Section Area Square Inches Cross-Section Area Square Centimeters Macrographs Up to 36, incl Up to 232, incl S2 - R1 - C2 Over 36 to 133, incl Over 232 t
22、o 858, incl S2 - R2 - C3 Over 133 Over 858 Note 1 Note 1 Limits for larger sizes shall be agreed upon by purchaser and producer. The purchaser shall have written approval of the agreement from the cognizant engineering organization. SAE INTERNATIONAL AMS6494B Page 4 of 7 3.3.2 Average Grain Size of
23、Bars, Mechanical Tubing and Forgings Average grain size shall be determined by either 3.3.2.1 or 3.3.2.2. 3.3.2.1 Shall be ASTM No. 5 or finer determined in accordance with ASTM E112. 3.3.2.2 The product of a heat shall be considered to have an ASTM No. 5 or finer austenitic grain size if the vanadi
24、um content is 0.02% minimum determined by heat analysis (see 8.5). 3.3.3 Response to Heat Treatment Specimens from the product shall have the properties shown in Table 3 after being austenitized by heating to 1760 F 25 F (960 C 14 C), holding at heat for a time commensurate with section thickness, h
25、eating equipment, and procedure used, oil quenched to below 90 F (32 C) followed by tempering for 2 hours minimum at 570 F 10 F (299 C 6 C). Table 3 - Minimum longitudinal mechanical properties Property Value Tensile Strength 181 ksi (1250 MPa) Yield Strength 0.2% 138 ksi (950 MPa) Elongation in 4D
26、12% Charpy Vnotch 37 ft-lb (50 J) 3.4 Quality The product, as received by purchaser, shall be uniform in quality and condition, sound, and free from foreign materials and from imperfections detrimental to usage of the product. 3.4.1 Steel shall be aircraft-quality conforming to AMS2301. 3.4.2 Bars a
27、nd mechanical tubing shall be free from seams, laps, tears, and cracks after removal of the standard stock removal allowance in accordance with AS1182. 3.4.3 Grain flow of die forgings, except in areas that contain flash-line end grain, shall follow the general contour of the forgings showing no evi
28、dence of reentrant grain flow. 3.5 Tolerances 3.5.1 Bars In accordance with AMS2251. 3.5.2 Mechanical Tubing In accordance with AMS2253. SAE INTERNATIONAL AMS6494B Page 5 of 7 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for Inspection The producer of the product shall supply all samples for p
29、roducers 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 product conforms to specified requirements. 4.2 Classification of Tests 4.2.1 Acceptance Tests Composi
30、tion (3.1), condition (3.2), macrostructure (3.3.1), average grain size (3.3.2), response to heat treatment (3.3.3), frequency-severity rating (3.4.1), and tolerances (3.5) are acceptance tests and shall be performed on each heat or lot as applicable. If grain refining element (3.3.2.2) is not prese
31、nt, the ASTM E112 grain size test (3.3.2.1) shall be conducted on each lot. 4.2.2 Periodic Tests If the grain refining element (3.3.2.2) is present, the ASTM E112 grain size test (3.3.2.1) may be conducted on a periodic basis and shall be performed at a frequency selected by the producer (not to exc
32、eed one year) unless frequency of testing is specified by purchaser. Grain flow of die forgings (3.4.3) is a periodic test and shall be performed at a frequency selected by the producer unless frequency of testing is specified by purchaser. 4.3 Sampling and Testing 4.3.1 Bars, Mechanical Tubing, and
33、 Forging Stock In accordance with AMS2370. 4.3.2 Forgings In accordance with AMS2372. 4.4 Reports 4.4.1 The producer of bars, forgings and mechanical tubing shall furnish with each shipment a report showing producer identity, country where the metal was melted (e.g., final melt in the case of metal
34、processed by multiple melting operations), the results of tests for composition, macrostructure and frequency-severity cleanliness rating of each heat, and for condition, average grain size if measured, and response to heat treatment of each lot, and stating that the product conforms to the other te
35、chnical requirements. This report shall include the purchase order number, heat and lot numbers, AMS6494B, product form and size or part number, and quantity. If forgings are supplied, the size and melt source of stock used to make the forgings shall also be included. If the grain size requirement o
36、f 3.3.2.2 is met by the vanadium, a statement that the chemistry satisfies the grain size requirement shall be included. 4.4.2 Report the nominal metallurgically worked cross sectional size and the cut size, if different (also see 3.2.1). 4.4.3 The producer of forging stock shall furnish with each s
37、hipment a report showing producer identity, country where the metal was melted (e.g., final melt in the case of metal processed by multiple melting operations) and the results of tests for composition, macrostructure, and frequency-severity rating of each heat and the results of any additional prope
38、rty requirements imposed by the purchase order (see 8.5). This report shall include the purchase order number, heat number, AMS6494B, size and quantity. SAE INTERNATIONAL AMS6494B Page 6 of 7 4.5 Resampling and Retesting 4.5.1 Bars, Mechanical Tubing, and Forging Stock In accordance with AMS2370. 4.
39、5.2 Forgings In accordance with AMS2372. 5. PREPARATION FOR DELIVERY 5.1 Sizes Except when exact lengths or multiples of exact lengths are ordered, straight bars and tubing will be acceptable 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 le
40、ngths shorter than 10 feet (3 m). 5.2 Identification 5.2.1 Bars and Mechanical Tubing In accordance with AMS2806. 5.2.2 Forgings In accordance with AMS2808. 5.2.3 Forging Stock As agreed upon by purchaser and producer. 5.3 Protective Treatment Bars and mechanical tubing ordered cold drawn, cold roll
41、ed, ground, turned, or polished shall be protected from corrosion prior to shipment. 5.4 Packaging The product 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 th
42、e product to ensure carrier acceptance and safe delivery. 6. ACKNOWLEDGMENT A producer shall include this specification number and its revision letter in all quotations and when acknowledging purchase orders. 7. REJECTIONS Product not conforming to this specification, or to modifications authorized
43、by purchaser, will be subject to rejection. SAE INTERNATIONAL AMS6494B Page 7 of 7 8. NOTES 8.1 Revision Indicator 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 issue o
44、f 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 Hardness conversion tables for metals ar
45、e presented in ASTM E140. 8.3 Terms used in AMS are clarified in ARP1917. 8.4 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 an
46、d are presented only for information. 8.5 Purchase documents should specify not less than the following: AMS6494B Product form and size or part number of product desired Quantity of product desired. If forging stock, any property data beyond that reported in 4.4.3. 8.6 When vanadium, a grain refiner
47、, is present above 0.02% the grain size resulting from using the appropriate test procedures per ASTM E112 will satisfy an ASTM 5 or finer requirement. Other technical societies have adopted the verification of fine grain steel based on chemistry alone. Included are ASTM International (Documents A6, A20, and A29); American Society of Mechanical Engineers (Documents SA6, SA20, and SA29); American Bureau of Shipping; CSA Group (Canada); EuroNorm documents; American Association of State Highway and Transportation Officials. PREPARED BY AMS COMMITTEE “E”
