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 2015 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/AMS6479DAEROSPACEMATERIAL SPECIFICATIONAMS6479 REV. DIssued 1996-08Revised 2015-10Superseding
5、 AMS6479CSteel, Bars, Forgings, and Tubing1.45Cr (0.93-1.05C) (SAE 52100)Special Aircraft-Quality Cleanliness(Composition similar to UNS G52986)RATIONALEAMS6479D results from a Five Year Review and update of this specification that revises decarburization requirements and reporting.1. SCOPE1.1 FormT
6、his specification covers a special 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 parts requiring a through-hardening steel, usually with hardness of approximately 60 HRC in section thic
7、knesses 0.50 inch (12.7 mm) and under, and subject to very rigid inspection standards, but usage is not limited to such applications.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 here
8、in. The supplier may 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 PublicationsAvailable from SAE
9、 International, 400 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 BarsAMS2253 Tolerances, Carbon and Alloy Steel TubingAMS2259 Chemical Check Analysis Limits, Wrought Low-All
10、oy and Carbon SteelsAMS2304 Steel Cleanliness, Special Aircraft-Quality Magnetic Particle Inspection ProcedureSAE INTERNATIONAL AMS6479D Page 2 of 8AMS2370 Quality Assurance Sampling and Testing, Carbon and Low-Alloy Steel Wrought Products and Forging StockAMS2372 Quality Assurance Sampling and Test
11、ing Carbon and Low-Alloy Steel ForgingsAMS2806 Identification Bars, Wire, Mechanical 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
12、Steel Bars and Mechanical Tubing2.2 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 A370 Mechanical Testing of Steel ProductsASTM E45 Determining the Inclusion Content of SteelASTM E350
13、Chemical Analysis of Carbon Steel, Low-Alloy Steel, Silicon Electrical Steel, Ingot Iron, and Wrought IronASTM E381 Macrotech Testing Steel Bars, Billets, Blooms, and ForgingsASTM E384 Knoop and Vickers Hardness of Materials3. TECHNICAL REQUIREMENTS3.1 CompositionShall conform to the percentages by
14、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 - CompositionElement min maxCarbon 0.93 1. 05Manganese 0.25 0.45Silicon 0.15 0.35Phosphorus - 0.015Sulfur - 0.015Chromi
15、um 1.30 1.60Nickel - 0.15Molybdenum - 0.08Copper - 0.15Titanium - 0.0030 (30 ppm)Oxygen - 0.0015 (15 ppm)Calcium - 0.0010 (10 ppm)SAE INTERNATIONAL AMS6479D Page 3 of 83.1.1 Check AnalysisComposition variations shall meet the applicable requirements of AMS2259.3.2 Melting PracticeSteel shall be melt
16、ed using ladle furnace melting and refining practice or other steel making practices acceptable to purchaser.3.3 ConditionThe product shall be supplied in the following condition; hardness and tensile strength shall be determined in accordance with ASTM A370.3.3.1 BarsBar shall not be cut from plate
17、 (also see 4.4.2).3.3.1.1 Bars 0.500 Inch (12.70 mm) and Under in Nominal Diameter or Least Distance Between Parallel SidesCold finished, with microstructure of spheroidized cementite in a ferrite matrix, having tensile strength not higher than 120 ksi (827 MPa) or equivalent hardness (see 8.2).3.3.
18、1.2 Bars Over 0.500 Inch (12.70 mm) in Nominal Diameter or Least Distance Between Parallel SidesHot finished and annealed, unless otherwise ordered, with microstructure of spheroidized cementite in a ferrite matrix, having hardness not higher than 207 HB, or equivalent (see 8.3). Bars ordered cold f
19、inished may have hardness as high as 248 HB, or equivalent (see 8.3).3.3.2 ForgingsAs ordered.3.3.3 Mechanical TubingCold finished, unless otherwise ordered, with microstructure of spheroidized cementite in a ferrite matrix, having hardness no higher than 24 HRC or equivalent (see 8.3). Tubing order
20、ed hot finished and annealed shall have hardness not higher than 95 HRB, or equivalent (see 8.3).3.3.4 Forging StockAs ordered by the forging manufacturer.3.4 PropertiesThe product shall conform to the following requirements; hardness testing shall be performed in accordance with ASTM A370.3.4.1 Mac
21、rostructureVisual 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, segregation, inclusions, and other imperfections shall be no worse than the macrog
22、raphs of ASTM E381 ratings S1, R1, and C1 for plate 1 and acceptable macrographs of plates 2 or 3 or as agreed upon by purchaser and producer.SAE INTERNATIONAL AMS6479D Page 4 of 83.4.2 Micro-Inclusion RatingNo specimen shall exceed the limits shown in Table 2, determined in accordance with ASTM E45
23、, Method D.Table 2 - Micro-inclusion rating limitsAThinAHeavyBThinBHeavyCThinCHeavyDThinDHeavyWorst Field Severity 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0Worst Field Frequency,Maximum a 1 a 1 a 1 5 3Total Rateable Fields,Frequency, Maximum b 1 b 1 b 1 c 3a - Combined A + B + C, no more than 3 fieldsb - Comb
24、ined A + B + C, not more than 8 fieldsc - Any number of lower rateable D-type thin fields per specimen is permissible.3.4.2.1 Thickness of D-type heavy shall not exceed 0.0005 inch (12.7 m).3.4.2.2 A rateable field is defined as one that has a type A, B, C, or D inclusion rating of at least 1.0 thin
25、 or heavy in accordance with ASTM E45. 3.4.3 Response to Heat Treatment of Bars, Forgings, and TubingSpecimens as in 4.3.3, protected by suitable means or treated in a neutral atmosphere or neutral salt to minimize scaling and prevent either carburization or decarburization, shall have substantially
26、 uniform hardness not lower than 63 HRC at any point below any permissible decarburization after being heated to 1525 F 10 F (829 C 6 C), held at heat for 20 minutes 2 minutes, and quenched in commercial paraffin oil (90 to 110 SUS at 100 F (38 C) at room temperature.3.4.4 Decarburization3.4.4.1 Bar
27、s and tubing ordered ground, turned, or polished shall be free from decarburization on the ground, turned, or polished surfaces. Decarburization on tubing ID shall not exceed the maximum depth specified in Table 3.3.4.4.2 Allowable decarburization of bars, billets, and tube rounds ordered for redraw
28、ing or forging or to specified microstructural requirements other than spheroidized cementite in a ferrite matrix shall be as agreed upon by purchaser and producer.3.4.4.3 Decarburization of bars that 3.4.4.1 or 3.4.4.2 is not applicable shall be not greater than shown in Table 3.3.4.4.4 Decarburiza
29、tion on the ID and OD of tubes that 3.4.4.1 or 3.4.4.2 is not applicable shall be not greater than that shown in Table 3.SAE INTERNATIONAL AMS6479D Page 5 of 8Table 3A - Maximum total depth of decarburization limits, inch/pound unitsNominal Diameteror Least DistanceBetween Parallel SidesInchesTotal
30、Depth ofDecarburizationBarsHot FinishedInchTotal Depth ofDecarburizationBarsAnnealedInchTotal Depth ofDecarburizationBarsCold FinishedInchTotal Depth ofDecarburizationTubesAnnealedInchTotal Depth ofDecarburizationTubesCold FinishedInchUp to 0.250, incl 0.005 0.015 0.003 0.012 0.010Over 0.250 to 0.50
31、0, incl 0.006 0.015 0.004 0.012 0.010Over 0.500 to 0.750, incl 0.008 0.015 0.006 0.012 0.010Over 0.750 to 1.000, incl 0.010 0.015 0.008 0.012 0.010Over 1.000 to 2.000, incl 0.017 0.022 0.015 0.020 0.014Over 2.000 to 3.000, incl 0.025 0.030 0.025 0.030 0.019Over 3.000 to 4.000, incl 0.035 0.045 0.035
32、 0.035 0.024Over 4.000 to 5.000, incl 0.055 0.065 0.055 0.040 0.028Table 3B - Maximum total depth of decarburization limits, SI unitsNominal Diameteror Least DistanceBetween Parallel SidesMillimetersTotal Depth ofDecarburizationBarsHot FinishedMillimeterTotal Depth ofDecarburizationBarsAnnealedMilli
33、meterTotal Depth ofDecarburizationBarsCold FinishedMillimeterTotal Depth ofDecarburizationTubesAnnealedMillimeterTotal Depth ofDecarburizationTubesCold FinishedMillimeterUp to 6.35, incl 0.13 0.38 0.08 0.30 0.25Over 6.35 to 12.70, incl 0.15 0.38 0.10 0.30 0.25Over 12.70 to 19.05, incl 0.20 0.38 0.15
34、 0.30 0.25Over 19.05 to 25.40, incl 0.25 0.38 0.20 0.30 0.25Over 25.40 to 50.80, incl 0.43 0.56 0.38 0.51 0.36Over 50.80 to 76.20, incl 0.64 0.76 0.64 0.76 0.48Over 76.20 to 101.60, incl 0.89 1.14 0.89 0.89 0.61Over101.60 to 127.00, incl 1.40 1.65 1.40 1.02 0.713.4.4.5 Decarburization shall be evalu
35、ated by one of the methods of 3.4.4.6 or 3.4.4.7, 3.4.4.6 Metallographic MethodA cross section taken perpendicular to the surface shall be prepared, etched, and visually examined metallographically at a magnification not to exceed 100X. The product shall not show a layer of complete (ferrite) or par
36、tial decarburization exceeding the limits of Table 3.3.4.4.7 Hardness Traverse MethodThe total depth of decarburization shall be determined by a traverse method using microhardness testing in accordance with ASTM E384, at a magnification not exceeding 100X, conducted on a hardened but untempered spe
37、cimen protected during heat treatment to prevent changes in surface carbon content. Tempering is generally not recommended, but if tempered, the tempering temperature shall be not higher than 300 F (149 C). Depth of decarburization is defined as the perpendicular distance from the surface to the dep
38、th under that surface where there is not further increase in hardness. Such measurements shall be far enough away from any adjacent surface to be uninfluenced by any decarburization on the adjacent surface. Acceptance shall be as listed in Table 3.3.4.4.8 When determining the depth of decarburizatio
39、n, it is permissible to disregard local areas provided the decarburization of such areas does not exceed the above limits by more than 0.005 inch (0.13 mm) and the width is 0.065 inch (1.65 mm) or less.3.4.4.9 In the case of dispute, the total depth of decarburization determined using the microhardn
40、ess traverse method shall govern.SAE INTERNATIONAL AMS6479D Page 6 of 83.5 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.3.5.1 Steel shall be special aircraft-
41、quality conforming to AMS2304.3.5.2 Bars and mechanical tubing ordered hot rolled or cold drawn, 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, ground, turned, or po
42、lished 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 accordance with AMS2253.4. QUA
43、LITY ASSURANCE PROVISIONS4.1 Responsibility for InspectionThe producer of the product shall supply all samples 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 en
44、sure 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), micro-inclusion rating (3.4.2), response to heat treatment (3.4.3), decarburization (3.4.4), frequency-severity cleanliness rating (3.
45、5.1), and tolerances (3.6) are acceptance tests and shall be performed on each heat or lot as applicable.4.2.2 Periodic TestsGrain flow of die forgings (3.5.3) 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
46、Sampling and Testing4.3.1 Bars, Mechanical Tubing, and Forging StockIn accordance with AMS2370.4.3.2 ForgingsIn accordance with AMS2372.SAE INTERNATIONAL AMS6479D Page 7 of 84.3.3 Samples for response to heat treatment (see 3.4.3) shall be as follows:4.3.3.1 Specimens from bars shall be full cross-s
47、ections of the bar, except length and width need not exceed 1.5 inches (38 mm) respectively, ground on both faces normal to the axis so that length is 0.50 inch 0.010 inch (12.7 mm 0.25 mm).4.3.3.2 Specimens from mechanical tubing shall be full cross-sections of the tubing, shall have wall thickness
48、 not over 0.625 inch (15.88 mm) with wall thicknesses over 0.625 inch (15.88 mm) being turned to 0.625 inch 0.010inch (15.88 mm 0.25 mm), and shall be ground on both faces so that length is 0.50 inch 0.010 inch (12.7 mm 0.25 mm).4.4 Reports4.4.1 The producer of bar, forgings, and tubing shall furnis
49、h with each shipment 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), the results of tests for composition, macrostructure, inclusion rating, and frequency-severity cleanliness rating of each heat and for the condition and response to heat treatment of each lot, and stating that the product conforms
