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/AMS6493AAEROSPACE MATERIAL SPECIFICATIONAMS6493 REV. AIssued 2009-09Revised 2013-11Supersedin
5、g AMS6493Steel Bars, Forgings, and Tubing1.0Cr - 3.25Ni - 0.40Mo (0.17 - 0.22C)Electroslag Remelted or Consumable Electrode Vacuum RemeltedPremium Aircraft-Quality(Composition similar to UNS K41910)RATIONALEAMS6493A results from a Five Year Review and update of this specification.1. SCOPE1.1 FormThi
6、s specification covers a premium aircraft-quality, low-alloy steel in the form of bars, forgings, mechanical tubing, and forging stock.1.2 ApplicationThese products have been used typically for carburized parts requiring high minimum core hardness with a narrow range, reduced distortion and subject
7、to stringent magnetic particle inspection standards, 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 speci
8、fic type is ordered, either type may be supplied.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 d
9、ocument 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.SAE INTERNATIONAL AMS6493A Page 2 of 72.1 SAE PublicationsAvailable from SAE International, 400 Commonwealth Drive, Warren
10、dale, PA 15096-0001, Tel: 877-606-7323 (inside USA 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, Pre
11、mium Aircraft-Quality, Magnetic Particle Inspection 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, Mechanica
12、l Tubing, and Extrusions, Carbon and Alloy Steels 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 Internat
13、ional, 100 Barr Harbor Drive, P. O. Box C700, West 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 D
14、etermining Average Grain SizeASTM E 350 Chemical 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 Tab
15、le 1, determined by wet chemical methods in accordance with ASTM E 350, by spectrochemical methods, or by other analytical methods acceptable to purchaser.SAE INTERNATIONAL AMS6493A Page 3 of 7TABLE 1 COMPOSITIONElement min maxCarbon 0.17 0.22Manganese 0.30 0.60Silicon - 0.40Phosphorus - 0.020Sulfur
16、 - 0.015Chromium 0.80 1.20Nickel 3.00 3.50Molybdenum 0.30 0.603.1.1 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 (V
17、AR) in the remelt 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
18、 Cold finished having tensile strength not higher than 138 ksi (950 MPa) or hardness not higher than 285 HB or equivalent (See 8.2).3.3.1.2 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 hardnes
19、s 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).3.3.1.3 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 2
20、85 HB, or 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).3.3.4 Forging Stock As ordered by the forging manufacturer.3.4 PropertiesThe product shall conform to the following requirements; hardness, tensile,
21、 and impact testing shall be performed in accordance with ASTM A 370:SAE INTERNATIONAL AMS6493A Page 4 of 73.4.1 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
22、 show no pipe or 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 Severity1Freckls A2 White Spots A3 Radial Segregation B4 Ring Pattern B3.4.2 Average Grain SizeShall
23、be ASTM No. 5 or 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 3 after being austenitized by heating to 1515 F 25 (824 C 14), holding at heat for a time commen
24、surate with section thickness, heating equipment, and procedure used, oil quenched to below 90 F (32 C) followed by tempering for 2 hours minimum at 285 F 10 (141 C 6).TABLE 3 MINIMUM LONGITUDINAL MECHANICAL PROPERTIESPROPERTY VALUETensile Strength 196 ksi (1350 MPa)Yield Strength 0.2% 152 ksi (1050
25、 MPa)Elongation in 4D 11%Charpy Vnotch 44 ft-lb (60 J)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 specimens taken from the stock after heat treatme
26、nt 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.3.5 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 o
27、f the product.3.5.1 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 ope
28、n to the machined, 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 Bars In accordance with AMS2251.SAE INTERNATION
29、AL AMS6493A Page 5 of 73.6.2 Mechanical Tubing In accordance 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 ri
30、ght to sample and to perform any confirmatory testing deemed necessary to ensure that the product conforms to specified requirements.4.2 Classification of Tests4.2.1 Acceptance TestsComposition (3.1), condition (3.3), macrostructure (3.4.1), average grain size (3.4.2), response to heat treatment (3.
31、4.3.1),and tolerances (3.6) are acceptance tests and shall be performed on each heat or lot as applicable.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
32、rformed at a frequency selected by the vendor unless frequency of testing is specified by purchaser.4.3 Sampling and Testing4.3.1 Bars, Mechanical Tubing, and Forging StockIn accordance with AMS2370.4.3.2 Forgings In accordance with AMS2372.4.4 Reports4.4.1 The producer of bars, forgings, and tubing
33、 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, macrostructure of each heat, and for condition, average grain siz
34、e, 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, AMS6493A, melt practice, product form and size or part number, and quantity. If forgings are supplied,
35、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 shipment a report showing the producer iden
36、tity and country where the metal was melted (e. g., final melt in the case of metal processed by multiple melting operations) and the composition and macrostructure of each heat. This report shall include the purchase order number, heat number, AMS6493A, size and quantity.4.5 Resampling and Retestin
37、g4.5.1 Bars, Mechanical Tubing, and Forging StockIn accordance with AMS2370.SAE INTERNATIONAL AMS6493A Page 6 of 74.5.2 Forgings In 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 accept
38、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 and Mechanical Tubing In accordance with AMS2806.5.2.2 Forgings In accordance with AMS2808.5.2.3 Forging StockAs agreed upon
39、by purchaser and vendor.5.3 Protective TreatmentBars and mechanical tubing ordered cold drawn, cold rolled, ground, turned, or polished 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
40、 with applicable rules and regulations pertaining to the handling, packaging, and transportation of the product to ensure carrier acceptance and safe delivery.6. ACKNOWLEDGMENTA vendor shall include this specification number and its revision letter in all quotations and when acknowledging purchase o
41、rders.7. REJECTIONSProduct not conforming to this specification, or to modifications authorized by purchaser, will be subject to rejection.8. NOTES8.1 A change bar (|) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial changes, ha
42、ve 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 and (R) are not used in original publications, nor in documents that contain editorial changes only.8.2 Hardn
43、ess conversion tables for metals are presented in ASTM E 140.8.3 Terms used in AMS are clarified in ARP1917.SAE INTERNATIONAL AMS6493A Page 7 of 78.4 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 for the primary units and are presented only for information.8.5 Purchase documents should specify not less than the following:AMS6493AProduct form and size or part number of product desiredQuantity of product desired.PREPARED BY AMS COMMITTEE “E”
