1、AEROSPACE MATERIAL SPECIFICATION AMS6472 REV. F Issued 1965-02 Reaffirmed 2006-02 Revised 2014-07 Superseding AMS6472E Steel, Bars and Forgings, Nitriding 1.6Cr - 0.35Mo - 1.1Al (0.38 - 0.43C) (135 Mod) Hardened and Tempered, 112 ksi (772 MPa) Tensile Strength (Composition similar to UNS K24065) RAT
2、IONALE AMS6472F results from a Five Year Review and update of this specification that revises cutting restrictions, macrostructure, decarburization, and reporting requirements. 1. SCOPE 1.1 Form This specification covers an aircraft-quality, low-alloy steel in the form of heat treated bars and forgi
3、ngs, and of forging stock. 1.2 Application This material has been used typically for nitrided parts requiring high surface hardness, resistance to heat, and less distortion than parts fabricated from steel requiring quenching to case harden, but usage is not limited to such applications. This steel
4、may be case hardened in dissociated ammonia gas to provide a minimum case hardness of 900 HV. 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 subsequ
5、ent 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, 400 Commonwealth Dri
6、ve, Warrendale, 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 Bars AMS2259 Chemical Check Analysis Limits, Wrought Low-Alloy and Carbon Steels AMS2301 Steel Cleanliness, Aircraft Quality, Magnetic Particle Ins
7、pection Procedure _ 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 infringe
8、ment arising therefrom, 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 2014 SAE International All rights reserved.
9、 No part of this 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) T
10、el: +1 724-776-4970 (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/AMS6472F SAE INTERNATIONAL AMS6472F Page 2 of 7 AMS2370 Quality
11、 Assurance Sampling and Testing, Carbon and Low-Alloy Steel Wrought Products and Forging Stock AMS2372 Quality Assurance Sampling and Testing, Carbon and Low-Alloy Steel Forgings AMS2750 Pyrometry AMS2806 Identification, Bars, Wire, Mechanical Tubing, and Extrusions, Carbon and Alloy Steels and Corr
12、osion and Heat-Resistant Steels and Alloys AMS2808 Identification, Forgings AS1182 Standard Stock Removal Allowance, 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 Cons
13、hohocken, PA 19428-2959, Tel: 610-832-9585, www.astm.org. ASTM A 370 Mechanical Testing of Steel Products ASTM E 350 Chemical Analysis of Carbon Steel, Low-Alloy Steel, Silicon Electrical Steel, Ingot Iron, and Wrought Iron ASTM E 381 Macroetch Testing Steel Bars, Billets, Blooms, and Forgings ASTM
14、E 384 Knoop and Vickers Hardness of Materials 3. TECHNICAL REQUIREMENTS 3.1 Composition Shall conform to the percentages by weight shown in Table 1, determined by wet chemical methods in accordance with ASTM E 350, by spectrochemical methods, or by other analytical methods acceptable to purchaser. T
15、ABLE 1 - COMPOSITION Element min max Carbon 0.38 0.43 Manganese 0.50 0.80 Silicon 0.20 0.40 Phosphorus - 0.025 Sulfur - 0.025 Chromium 1.40 1.80 Molybdenum 0.30 0.40 Aluminum 0.95 1.30 Nickel - 0.25 Copper - 0.35 3.1.1 Check Analysis Composition variations shall meet the applicable requirements of A
16、MS2259. 3.2 Condition The product shall be supplied in the following condition: SAE INTERNATIONAL AMS6472F Page 3 of 7 3.2.1 Bars Bar shall be hardened and tempered. Bar shall not be cut from plate (Also see 4.4.2). 3.2.2 Forgings Hardened and tempered 3.2.3 Forging Stock As ordered by the forging m
17、anufacturer. 3.3 Heat Treatment Bars and forgings shall be hardened by quenching from 1700 F 25 (927 C 14) and tempered to meet the tensile property requirements of 3.4.2. Pyrometry shall be in accordance with AMS2750. 3.4 Properties The product shall conform to the following requirements; hardness
18、and tensile testing shall be performed in accordance with ASTM A 370: 3.4.1 Macrostructure Visual examination of transverse full cross sections from bars and forging stock, etched in hot hydrochloric acid in accordance with ASTM E 381 shall show no pipe or cracks. Porosity, segregation, inclusions,
19、and other imperfections shall be no worse than the macrographs of ASTM E 381 shown in Table 2. TABLE 2 - MACROSTRUCTURE LIMITS Cross-Sectional Area Square Inches Cross-Sectional Area Square Centimeters Macrographs Up to 36, incl Up to 232, incl S2 - R1 - C2 Over 36 to 133, incl Over 232 to 858, incl
20、 S2 - R2 - C3 Over 133 Over 858 Note 1 Note 1: Limits for larger sizes shall be agreed upon by purchaser and vendor. The purchaser shall have written approval from the cognizant engineering organization 3.4.2 Tensile Properties of Bars and Forgings Shall be as shown in Table 3. TABLE 3 - MINIMUM TEN
21、SILE PROPERTIES Property Value Tensile Strength 112 ksi (772 MPa) Yield Strength at 0.2% Offset 90 ksi (620 MPa) Elongation in 4D 16% Reduction of Area 50% 3.4.3 Hardness of Bars and Forgings Shall be as shown in Table 4. SAE INTERNATIONAL AMS6472F Page 4 of 7 TABLE 4 - HARDNESS Nominal Diameter or
22、Least Section Thickness Inches Nominal Diameter or Least Section Thickness Millimeters Hardness Brinell Up to 3.125, incl Up to 79.38, incl 241 to 285 Over 3.125 to 6.000, incl Over 79.38 to 152.40, incl 229 to 285 3.4.3.1 Brinell hardness, or equivalent (See 8.2), shall be determined midway between
23、 surface and center of bars. 3.4.4 Decarburization 3.4.4.1 Bars ordered ground, turned, or polished shall be free from decarburization on the ground, turned, or polished surfaces. 3.4.4.2 Allowable decarburization of bars and billets ordered for redrawing or forging or to specified microstructural r
24、equirements shall be as agreed upon by purchaser and 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. TABLE 5A - MAXIMUM TOTAL DEPTH OF DECARBURIZATION LIMITS, INCH/POUND UNITS Nominal Diameter or Distance Between Paral
25、lel Sides Inches Total Depth of Decarburization Inch Up to 0.500, incl 0.030 Over 0.500 to 1.000, incl 0.035 Over 1.000 to 1.500, incl 0.040 Over 1.500 to 2.000, incl 0.050 Over 2.000 to 2.500, incl 0.060 Over 2.500 to 3.000, incl 0.070 TABLE 5B - MAXIMUM TOTAL DEPTH OF DECARBURIZATION LIMITS, SI UN
26、ITS Nominal Diameter or Distance Between Parallel Sides Millimeters Total Depth of Decarburization Millimeters Up to 12.70, incl 0.76 Over 12.70 to 25.40, incl 0.89 Over 25.40 to 38.10, incl 1.02 Over 38.10 to 50.80, incl 1.27 Over 50.80 to 63.50, incl 1.52 Over 63.50 to 76.20, incl 1.78 3.4.4.4 Dec
27、arburization shall be measured by the metallographic method or by the microhardness 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 surfa
28、ce carbon content. Depth of decarburization, when measured by a 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 u
29、ninfluenced by any decarburization on the adjacent surface. In case of dispute, the depth of decarburization determined using the microhardness traverse method shall govern. 3.4.4.4.1 When determining the depth of decarburization, it is permissible to disregard local areas provided the decarburizati
30、on 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. SAE INTERNATIONAL AMS6472F Page 5 of 7 3.5 Quality The product, as received by purchaser, shall be uniform in quality and condition, sound, and free from foreign materia
31、ls and from imperfections detrimental to usage of the product. 3.5.1 Steel shall be aircraft-quality conforming to AMS2301. 3.5.2 Bars ordered hot rolled or cold drawn or ground, turned, or polished, shall, after removal of the standard stock removal allowance in accordance with AS1182, be free from
32、 seams, laps, tears, and cracks open 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 Tolerances Bars shall conf
33、orm to all applicable requirements of AMS2251. 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for Inspection The 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 perf
34、orm any confirmatory testing deemed necessary to ensure that the product conforms to specified requirements. 4.2 Classification of Tests 4.2.1 Acceptance Tests Composition (3.1), condition (3.2), macrostructure (3.4.1), tensile properties (3.4.2), hardness (3.4.3), decarburization (3.4.4), frequency
35、-severity cleanliness ratings (3.5.1) and tolerances (3.6), are acceptance tests and shall be performed on each heat or lot as applicable. 4.2.2 Periodic Tests Grain flow of die forgings (3.5.3) is a periodic test and shall be performed at a frequency selected by the vendor unless a frequency of tes
36、ting is specified by purchaser. 4.3 Sampling and Testing 4.3.1 Bars and Forging Stock In accordance withAMS2370. 4.3.2 Forgings In accordance AMS2372. SAE INTERNATIONAL AMS6472F Page 6 of 7 4.4 Reports 4.4.1 The producer of bars and forgings shall furnish with each shipment a report showing the prod
37、ucer 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, and frequency-severity cleanliness rating of each heat and for tensile properties and hardness of each lot, and s
38、tating that the product conforms to the other technical requirements. This report shall include the purchase order number, heat and lot numbers, AMS6472F, product form and size (and/or part number, if applicable), and quantity. If forgings are supplied, the size and melt source of stock used to make
39、 the forgings shall also 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 shipment a report showing the producer identity, country where the metal was melted
40、(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 cleanliness rating of each heat. This report shall include the purchase order number, heat number, AMS6472F, size and quantity 4.5 Resamp
41、ling and Retesting 4.5.1 Bars and Forging Stock In accordance with AMS2370. 4.5.2 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 will be acceptable in mill lengths of 6 to 20 feet (1.8 to 6
42、.1 m) but not more than 10% of any shipment shall be supplied in lengths shorter than 10 feet (3 m). 5.2 Identification 5.2.1 Bars In accordance with AMS2806. 5.2.2 Forgings In accordance with AMS2808. 5.2.3 Forging Stock As agreed upon by purchaser and vendor. 5.3 Protective Treatment Bars ordered
43、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 the pr
44、oduct to ensure carrier acceptance and safe delivery. SAE INTERNATIONAL AMS6472F Page 7 of 7 6. ACKNOWLEDGMENT A vendor 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
45、, or to modifications authorized by purchaser, will be subject to rejection. 8. NOTES 8.1 A change bar (|) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial changes, have been made to the previous issue of this document. An (R) s
46、ymbol 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 are presented in ASTM E 140
47、. 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 and are presented only for
48、 information. 8.5 Purchase documents should specify not less than the following: AMS6472F Product form and size or part number of product desired Quantity of product desired For forging stock provide specific instructions if capability testing response to heat treatment is required (See 3.3, 3.4.2, and 3.4.3). 8.6 Similar Specifications MIL-S-6709 PREPARED BY AMS COMMITTEE “E“
