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/AMS6497AAEROSPACE MATERIAL SPECIFICATIONAMS6497 REV. AIssued 2009-09Revised 2013-11Supersedin
5、g AMS6497Steel Bars, Forgings, and Tubing, Nitriding1.4Cr - 1.2Mo - 0.3V (0.29 - 0.36C)Electroslag Remelted or Consumable Electrode Vacuum RemeltedPremium Aircraft-Quality for Bearing Applications(Composition similar to UNS K23280)RATIONALEAMS6497A results from a Five Year Review and update of this
6、specification.1. SCOPE1.1 FormThis specification covers a nitriding grade of premium aircraft-quality, low-alloy steel in the form of bars, forgings, mechanical tubing, and forging stock. AMS6496 and AMS6498 cover UNS K23280 with other quality levels.1.2 ApplicationThese products have been used typi
7、cally for nitrided parts such as bearings, operating under heavy loads and high speeds at moderate temperatures, and subject to very rigid inspection standards, and requiring highest surface hardness, high core toughness, and less distortion than parts made from steel requiring quenching to case har
8、den, but usage is not limited to such applications.1.3 ClassificationSteel covered by this specification is classified by melting practice as follows:Type 1 Electroslag remelted (ESR)Type 2 Consumable electrode vacuum remelted (VAR)1.3.1 Unless a specific type is ordered, either type may be supplied
9、.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 referenced
10、document has been cancelled and no superseding document has been specified, the last published issue of that document shall apply.SAE INTERNATIONAL AMS6497A Page 2 of 82.1 SAE PublicationsAvailable from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside U
11、SA and Canada) or 724-776-4970 (outside USA), www.sae.org.AMS2251 Tolerances, Low-Alloy Steel BarsAMS2253 Tolerances, Carbon and Alloy Steel TubingAMS2259 Chemical Check Analysis Limits, Wrought Low-Alloy and Carbon SteelsAMS2300 Steel Cleanliness, Premium Aircraft-Quality, Magnetic Particle Inspect
12、ion ProcedureAMS2370 Quality Assurance Sampling and Testing, Carbon and Low-Alloy Steel Wrought Products and Forging StockAMS2372 Quality Assurance Sampling and Testing, Carbon and Low-Alloy Steel Forgings AMS2806 Identification, Bars, Wire, Mechanical Tubing, and Extrusions, Carbon and Alloy Steels
13、 and Corrosion and Heat-Resistant Steels and AlloysAMS2808 Identification, ForgingsAS1182 Standard Stock Removal Allowance, Aircraft-Quality and Premium Aircraft-Quality Steel Bars and Mechanical Tubing2.2 ASTM PublicationsAvailable from ASTM International, 100 Barr Harbor Drive, P. O. Box C700, Wes
14、t Conshohocken, PA 19428-2959, Tel: 610-832-9585, www.astm.org.ASTM A 255 Determining Hardenability of SteelASTM A 370 Mechanical Testing of Steel ProductsASTM A 604 Macroetch Testing of Consumable Electrode Remelted Steel Bars and BilletsASTM E 112 Determining Average Grain SizeASTM E 350 Chemical
15、Analysis of Carbon Steel, Low-Alloy Steel, Silicon Electrical Steel,Ingot Iron, and Wrought IronASTM E 384 Knoop and Vickers Hardness of Materials3. TECHNICAL REQUIREMENTS3.1 CompositionShall conform to the following percentages by weight shown in Table 1, determined by wet chemical methods in accor
16、dance with ASTM E 350, by spectrochemical methods, or by other analytical methods acceptable to purchaser.SAE INTERNATIONAL AMS6497A Page 3 of 8TABLE 1 COMPOSITIONElement min maxCarbon 0.29 0.36Manganese 0.70 1.20Silicon - 0.30Phosphorus - 0.015Sulfur - 0.005Chromium 1.10 1.60Nickel 0.50 1.00Molybde
17、num 0.90 1.40Aluminum 0.10 0.30Vanadium 0.20 0.403.1.1 Check AnalysisComposition variations shall meet the applicable requirements of AMS2259.3.2 Melting Practice Steel shall be multiple melted using either electroslag remelt practice (ESR) or vacuum arc consumable electrode practice (VAR) in the re
18、melt cycle (See 1.3).3.3 ConditionThe product shall be supplied in the following condition; hardness and tensile strength shall be determined in accordance with ASTM A 370:3.3.1 Bars3.3.1.1 Bars 0.500 inch (12.70 mm) and Under in Nominal Diameter or Least Distance Between Parallel Sides Cold finishe
19、d having tensile strength not higher than 138 ksi (950 MPa) or hardness not higher than 285 HB or equivalent (See 8.2).3.3.1.2 Bars over 0.500 inch (12.70 mm) in Nominal Diameter or Least Distance Between Parallel Sides Hot finished and annealed, unless otherwise ordered, having hardness not higher
20、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).3.3.1.3 Bars shall not be cut from plate.3.3.2 ForgingsAs ordered.3.3.3 Mechanical TubingCold finished, unless otherwise ordered, having hardness not higher than 285 HB, or equ
21、ivalent (See 8.2). Tubing ordered hot finished and annealed or tempered shall have hardness not higher than 285 HB or equivalent (See 8.2).3.3.4 Forging Stock As ordered by the forging manufacturer.3.4 PropertiesThe product shall conform to the following requirements; hardness, tensile and impact te
22、sting shall be performed in accordance with ASTM A 370:SAE INTERNATIONAL AMS6497A Page 4 of 83.4.1 MacrostructureVisual examination of transverse full cross-sections from bars, billets, tube rounds and forging stock, etched in hot hydrochloric acid in accordance with ASTM A 604, shall show no pipe o
23、r cracks. Porosity, segregation, inclusions, and other imperfections shall be no worse than the macrographs of ASTM A 604 shown in Table 2.TABLE 2 MACROSTRUCTURE LIMITSClass Condition Severity1FrecklsA2 White Spots A3 Radial Segregation B4 Ring Pattern B3.4.2 Average Grain SizeShall be ASTM No. 6 or
24、 finer determined in accordance with ASTM E 112.3.4.3 Response to Heat Treatment3.4.3.1 Bars, Forgings and Mechanical TubingSpecimens from product shall have the properties shown in Table 4 after being austenitized by heating to 1720 F 25 (938 C 14), holding at heat for a time commensurate with sect
25、ion thickness, heating equipment, and procedure used, oil quenched below 90 F (32 C) followed by tempering for 2 hours minimum at no lower than 1110 F (599 C).TABLE 4 LONGITUDINAL MECHANICAL PROPERTIESPROPERTY VALUETensile Strength, min 181 ksi (1250 MPa)Yield Strength 0.2%, min 155 ksi (1070 MPa)El
26、ongation in 4D, min 11%Charpy Vnotch, min 18 ft-lb (25 J)Hardness 375 to 450 HB, or equivalent (See 8.2)3.4.3.2 Forging StockWhen a sample of stock is forged to a test coupon and heat treated as in 3.4.3.1, specimens taken from the heat treated coupon shall conform to the requirements of 3.4.3.1. If
27、 specimens taken from the stock after heat treatment as in 3.4.3.1 conform to the requirements of 3.4.3.1, tests shall be accepted as equivalent to tests of a forged coupon.3.4.4 Decarburization3.4.4.1 Bars and tubing ordered ground, turned, or polished shall be free from decarburization on the grou
28、nd, turned or polished surfaces. Decarburization on tubing ID shall not exceed the maximum depth specified in Table 6.3.4.4.2 Allowable decarburization of bars, billets, and tube rounds ordered for redrawing or forging or to specified microstructural requirements shall be as agreed upon purchaser an
29、d vendor.3.4.4.3 Decarburization of bars to which 3.4.4.1 or 3.4.4.2 is not applicable shall be not greater than shown in Table 5.SAE INTERNATIONAL AMS6497A Page 5 of 8TABLE 5A - MAXIMUM TOTAL DEPTH OF DECARBURIZATION, BARS, INCH/POUND UNITSNominal Diameter or DistanceBetween Parallel SidesInchesTot
30、al Depthof DecarburizationInchUp to 0.500, incl 0.030Over 0.500 to 1.000, incl 0.035Over 1.000 to 1.500, incl 0.040Over 1.500 to 2.000, incl 0.050Over 2.000 to 2.500, incl 0.060Over 2.500 to 3.000, incl 0.070Over 3.000 0.080TABLE 5B - MAXIMUM TOTAL DEPTH OF DECARBURIZATION, BARS, SI UNITSNominal Dia
31、meter or DistanceBetween Parallel SidesMillimetersTotal Depthof DecarburizationMillimetersUp to 12.70, incl 0.76Over 12.70 to 25.40, incl 0.89Over 25.40 to 38.10, incl 1.02Over 38.10 to 50.80, incl 1.27Over 50.80 to 63.50, incl 1.52Over 63.50 to 76.20, incl 1.78Over 76.20 2.043.4.4.4 Decarburization
32、 of tubing to which 3.4.4.1 or 3.4.4.2 is not applicable shall be not greater than shown in Table 6.TABLE 6A - MAXIMUM TOTAL DEPTH OF DECARBURIZATION, TUBING, INCH/POUND UNITSNominal Wall ThicknessInchesTotal Depth of DecarburizationInchIDTotal Depth of DecarburizationInchODUp to 0.109, incl 0.008 0
33、.015Over 0.109 to 0.203, incl 0.010 0.020Over 0.203 to 0.400, incl 0.012 0.025Over 0.400 to 0.600, incl 0.015 0.030Over 0.600 to 1.000, incl 0.017 0.035Over 1.000 0.020 0.040TABLE 6B - MAXIMUM TOTAL DEPTH OF DECARBURIZATION, TUBING, SI UNITSNominal Wall ThicknessMillimetersTotal Depth of Decarburiza
34、tionMillimeterIDTotal Depth of DecarburizationMillimetersODUp to 2.77, incl 0.20 0.38Over 2.77 to 5.16, incl 0.25 0.51Over 5.16 to 10.16, incl 0.30 0.64Over 10.16 to 15.24, incl 0.38 0.76Over 15.24 to 25.40, incl 0.43 0.89Over 25.40 0.51 1.02SAE INTERNATIONAL AMS6497A Page 6 of 83.4.4.5 Decarburizat
35、ion shall be measured by the metallographic method or by a traverse method using microhardness testing in accordance with ASTM E 384. The microhardness method shall be conducted on a hardened but untempered specimen protected during heat treatment to prevent changes in surface carbon content. Depth
36、of decarburization, when measured by the microhardness method, is defined as the perpendicular distance from the surface to the depth under that surface where there is no further increase in hardness. Such measurements shall be far enough away from any adjacent surface to be uninfluenced by any deca
37、rburization on the adjacent surface. In case of dispute, the depth of decarburization determined using the microhardness traverse method shall govern.3.4.4.5.1 When determining the depth of decarburization, it is permissible to disregard local areas provided the decarburization of such areas does no
38、t exceed the above limits by more than 0.005 inch (0.12 mm) and the width is 0.065 inch (1.65 mm) or less.3.5 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 of the product.3.5
39、.1 Steel shall be premium aircraft-quality conforming to AMS2300.3.5.2 Product ordered hot finished or cold finished or ground, turned, or polished shall, after removal of the standard stock removal allowance in accordance with AS1182, be free from seams, laps, tears, and cracks open to the machined
40、, ground, turned, or polished surface.3.5.3 Grain flow of die forgings, except in areas that contain flash-line end grain, shall follow the general contour of the forgings showing no evidence of reentrant grain flow.3.6 Tolerances3.6.1 BarsIn accordance with AMS2251.3.6.2 Mechanical TubingIn accorda
41、nce with AMS2253.4. QUALITY ASSURANCE PROVISIONS4.1 Responsibility for inspectionThe vendor of the product shall supply all samples for vendors tests and shall be responsible for the performance of all required tests. Purchaser reserves the right to sample and to perform any confirmatory testing dee
42、med necessary to ensure that the product conforms to specified requirements.4.2 Classification of Tests4.2.1 Acceptance Tests4.2.1.1 Composition (3.1), condition (3.3), macrostructure (3.4.1), average grain size (3.4.2), response to heat treatment (3.4.3.1), and tolerances (3.6) are acceptance tests
43、 and shall be performed on each heat or lot as applicable.4.2.1.2 When specified, decarburization (3.4.4).4.2.2 Periodic TestsFrequency-severity cleanliness rating (3.5.1), grain flow of die forgings (3.5.3) and response to heat treatment of forging stock (3.4.3.2) are periodic tests and shall be pe
44、rformed at a frequency selected by the vendor unless frequency of testing is specified by purchaser.SAE INTERNATIONAL AMS6497A Page 7 of 84.3 Sampling and Testing4.3.1 Bars, Mechanical Tubing, and Forging Stock In accordance with AMS2370.4.3.2 Forgings In accordance with AMS2372.4.4 Reports4.4.1 The
45、 producer of bars, forgings and tubing shall furnish with each shipment a report showing the producer identity and country where the metal was melted (i.e., final melt in the case of metal processed by multiple melting operations) and the results of tests for composition and macrostructure of each h
46、eat, and for condition, average grain size, and response to heat treatment of each lot, and stating that the product conforms to the other technical requirements. This report shall include the purchase order number, heat and lot numbers, AMS6497A, melt practice, product form and size or part number,
47、 and quantity. If forgings are supplied, the size and melt source of stock used to make the forgings shall also be included.4.4.2 Report the nominal metallurgically worked cross sectional size and the cut size, if different (See 3.3.1.3).4.4.3 The producer of forging stock shall furnish with each sh
48、ipment a report showing the producer identity and country where the metal was melted (e. g., final melt in the case of metal processed by multiple melting operations) and the composition, macrostructure and frequency-severity cleanliness rating of each heat. This report shall include the purchase or
49、der number, heat number, AMS6497A, size and quantity.4.5 Resampling and Retesting4.5.1 Bars, Mechanical Tubing, and Forging StockIn accordance with AMS2370.4.5.2 ForgingsIn accordance with AMS2372.5. PREPARATION FOR DELIVERY5.1 SizesExcept 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 shipme