SAE AMS 6476E-2016 Steel Bars Forgings and Tubing 0 50Cr - 0 12Mo (0 89 - 1 01C) (UNS K19526).pdf

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/AMS6476E AEROSPACE MATERIAL SPECIFICATION AMS6476 REV. E Issued 1988-04 Revised 2

5、016-09Superseding AMS6476D Steel, Bars, Forgings, and Tubing 0.50Cr - 0.12Mo (0.89 - 1.01C) (Composition similar to UNS K19526)RATIONALE AMS6476E results from a Five Year Review and update of this specification that revises macrostructure (3.3.1), test procedure for decarburization (3.3.4.4), and re

6、porting (4.4). 1. SCOPE 1.1 Form This specification covers a low-alloy steel in the form of bars, forgings, mechanical tubing, and forging or tubing stock. 1.2 Application These products have been used typically for bearing components requiring a through-hardening steel usually with hardness of appr

7、oximately 60 HRC and section thickness under 0.50 inch (12.7 mm), 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 ma

8、y 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, 4

9、00 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 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-Alloy Steel Forgings SAE INTERNATIONAL AMS6476E Page 2 of 8 AMS2806 Identification Bars, Wire, Mechanical Tubing, and Extrusio

11、ns 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 Allowance Aircraft-Quality and Premium Aircraft-Quality Steel Bars and Mechanical Tubing

12、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 E45 Determining the Inclusion Content of Steel ASTM E140 Hardness Conversion Tables fo

13、r Metals ASTM E350 Chemical Analysis of Carbon Steel, Low-Alloy Steel, Silicon Electrical Steel, Ingot Iron, and Wrought Iron ASTM E381 Macroetch Testing Steel Bars, Billets, Blooms, and Forgings ASTM E384 Microindentation Hardness Testing of Materials 3. TECHNICAL REQUIREMENTS 3.1 Composition Shall

14、 conform to the 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 Element min max Carbon Manganese Silicon Phosphorus Sulfur Chromium Molyb

15、denum Nickel Copper 0.89 0.50 0.15 - - 0.40 0.08 - - 1.01 0.80 0.35 0.025 0.025 0.60 0.15 0.25 0.35 SAE INTERNATIONAL AMS6476E Page 3 of 8 3.1.1 Check Analysis Composition variations shall meet the applicable requirements of AMS2259. 3.2 Condition The product shall be supplied in the following condi

16、tion; 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 Distance Between Parallel Sides Cold finished, with microstructure of spheroidi

17、zed cementite in a ferrite matrix, having tensile strength not higher than 120 ksi (827 MPa), or equivalent hardness (see 8.2). 3.2.1.2 Bars Over 0.500 Inch (12.70 mm) in Nominal Diameter or Least Distance Between Parallel Sides Unless otherwise ordered, hot finished and annealed, with microstructur

18、e of spheroidized cementite in a ferrite matrix, having hardness not higher than 207 HB, or equivalent (see 8.3). Bars ordered cold finished may have hardness as high as 248 HB, or equivalent (see 8.3). 3.2.2 Forgings As ordered. 3.2.3 Mechanical Tubing Unless otherwise ordered, cold finished with m

19、icrostructure of spheroidized cementite in ferrite matrix. Tubing ordered hot finished and annealed shall have hardness not higher than 95 HRB, or equivalent (see 8.3). 3.2.4 Forging or Tubing Stock As ordered by the forging or tubing manufacturer. 3.3 Properties The product shall conform to the fol

20、lowing requirements; hardness 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 cra

21、cks. Porosity, segregation, inclusions, and other imperfections shall be no worse than the macrographs of ASTM E381 shown in Table 2. Table 2 - Maximum macrostructure ratings Section Size Square Inches Section Size Square Centimeters Macrographs Up to 36, incl Over 36 to 133, incl Over 133 Up to 232

22、, incl Over 232 to 858, incl Over 858 S2 - R1 - C2 S2 - R2 - C3 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 AMS6476E Page 4 of 8 3.3.1.

23、1 If tubes are produced directly from ingots or large blooms, transverse sections may be taken from the tubes rather than tube rounds. Macroetch standards for such tubes shall be as agreed upon by purchaser and producer. 3.3.2 Micro-Inclusion Rating of Each Heat One or more specimens from each ingot

24、 tested, as well as two-thirds of the total number of specimens and the average of all specimens, shall not exceed the limits shown in Table 3, determined in accordance with ASTM E45, Method A. Table 3 - Micro-inclusion rating Type A B C D Thin Heavy 2.5 1.5 2.0 1.0 0.5 0.5 1.0 1.0 3.3.3 Response to

25、 Heat Treatment for Bars, Forgings, and Tubing Specimens as in 4.3.3, protected by suitable means or treated in a neutral atmosphere to minimize scaling and prevent either carburization or decarburization, shall have substantially uniform hardness not lower than 63 HRC at any point below any permiss

26、ible decarburization after being placed in a furnace which is at 1525 F 10 F (829 C 6 C), allowed to heat 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. 3.3.4 Decarburization 3.3.4.1 Bars

27、and tubing ordered ground, turned, or polished shall be free from decarburization on the ground, turned, or polished surfaces. Decarburization on the tubing ID shall not exceed the maximum depth specified in Table 4. 3.3.4.2 Allowable decarburization of bars, billets, and tube rounds ordered for red

28、rawing or forging or to specified microstructural requirements other than spheroidized cementite in a ferrite matrix shall be as agreed upon by purchaser and producer. 3.3.4.3 Decarburization of bars and of the ID and OD of tubes that 3.3.4.1 or 3.3.4.2 is not applicable shall be not greater than sh

29、own in Table 4. Table 4A - Maximum decarburization limits, inch/pound units Nominal Diameter or Distance Between Parallel Sides Inches Total Depth of Decarburization Bars, Hot Finished Inch Total Depth of Decarburization Bars Annealed Inch Total Depth of Decarburization Bars, Cold Finished Inch Tota

30、l Depth of Decarburization Tubes Annealed Inch Total Depth of Decarburization Tubes, Cold Finished Inch Up to 0.250, incl Over 0.250 to 0.500, incl Over 0.500 to 0.750, incl Over 0.750 to 1.000, incl Over 1.000 to 2.000, incl Over 2.000 to 3.000, incl Over 3.000 to 4.000, incl Over 4.000 to 5.000, i

31、ncl 0.005 0.006 0.008 0.010 0.017 0.025 0.035 0.055 0.015 0.015 0.015 0.015 0.022 0.030 0.045 0.065 0.003 0.004 0.006 0.008 0.015 0.025 0.035 0.055 0.012 0.012 0.012 0.012 0.020 0.030 0.035 0.040 0.010 0.010 0.010 0.010 0.014 0.019 0.024 0.028 SAE INTERNATIONAL AMS6476E Page 5 of 8 Table 4B - Maximu

32、m decarburization limits, SI units Nominal Diameter or Distance Between Parallel Sides Millimeters Total Depth of Decarburization Bars, Hot Finished Millimeters Total Depth of Decarburization Bars Annealed Millimeters Total Depth of Decarburization Bars, Cold Finished Millimeters Total Depth of Deca

33、rburization Tubes Annealed Millimeters Total Depth of Decarburization Tubes, Cold Finished Millimeter Up to 6.35, incl Over 6.35 to 12.70, incl Over 12.70 to 19.05, incl Over 19.05 to 25.40, incl Over 25.40 to 50.80, incl Over 50.80 to 76.20, incl Over 76.20 to 101.60, incl Over 101.60 to 127.00, in

34、cl 0.13 0.15 0.20 0.25 0.43 0.64 0.89 1.40 0.38 0.38 0.38 0.38 0.56 0.76 1.14 1.65 0.08 0.10 0.15 0.20 0.38 0.64 0.89 1.40 0.30 0.30 0.30 0.30 0.51 0.76 0.89 1.02 0.25 0.25 0.25 0.25 0.36 0.48 0.61 0.71 3.3.4.4 Decarburization shall be evaluated by one of the two methods of 3.3.4.4.1 or 3.3.4.4.2. 3

35、.3.4.4.1 Metallographic Method A cross section taken perpendicular to the surface shall be prepared, etched, and visually examined metallographically at a magnification not to exceed 100X. Optical indications of decarburiztion shall not show a layer of complete (ferrite) or partial decarburization e

36、xceeding the limits of Table 4. 3.3.4.4.2 Hardness Traverse Method The total depth of decarburization shall be determined by a traverse method using microindentation hardness testing in accordance with ASTM E384, at a magnification not exceeding 100X, conducted on a hardened but untempered specimen

37、protected during heat treatment to prevent changes in surface carbon content. Depth of decarburization is defined as the perpendicular distance from the surface to the depth under that surface where there is not further increase in hardness. Such measurements shall be far enough away from any adjace

38、nt surface to be uninfluenced by any decarburization on the adjacent surface. Acceptance shall be as listed in Table 4. 3.3.4.5 When determining the depth of decarburization, it is permissible to disregard local areas provided the decarburization of such areas does not exceed the above limits by mor

39、e than 0.005 inch (0.13 mm) and the width is 0.065 inch (1.65 mm) or less. 3.3.4.6 In case of dispute, the total depth of decarburization determined using the microindentation hardness traverse method shall govern. 3.4 Quality The product, as received by purchaser, shall be uniform in quality and co

40、ndition, sound, and free from foreign materials and from imperfections detrimental to usage of the product. 3.4.1 Bars and mechanical tubing shall be free from seams, laps, tears, and cracks after removal of the standard stock removal allowance in accordance with AS1182. 3.4.2 Grain flow of die forg

41、ings, except in areas that contain flash-line end grain, shall follow the general contour of the forgings showing no evidence of reentrant grain flow. SAE INTERNATIONAL AMS6476E Page 6 of 8 3.5 Tolerances Shall be as follows: 3.5.1 Bars In accordance with AMS2251. 3.5.2 Mechanical Tubing In accordan

42、ce with AMS2253. 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for Inspection The 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 testi

43、ng 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 (3.3.1), micro-inclusion rating (3.3.2), response to heat treatment (3.3.3), decarburization (3.3.4), and tolerance

44、 (3.5) are acceptance tests and shall be performed on each heat or lot, as applicable. 4.2.2 Periodic Tests Grain flow of die forgings (3.4.2) 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 Tes

45、ting 4.3.1 Bars, Mechanical Tubing, and Forging or Tubing Stock In accordance with AMS2370. 4.3.2 Forgings In accordance with AMS2372. 4.3.3 Samples for response to heat treatment (3.3.3) shall be as follows: 4.3.3.1 Specimens from bars shall be full cross-sections of the bar machined on both faces

46、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 not over 0.625 inch (15.88 mm), with wall thicknesses over 0.625 inch (15.88 mm) being turned to 0.625 inch 0.01

47、0 inch (15.88 mm 0.25 mm), and shall be machined on both faces so that length is 0.50 inch 0.010 inch (12.7 mm 0.25 mm). SAE INTERNATIONAL AMS6476E Page 7 of 8 4.4 Reports 4.4.1 The producer of the bars, forgings, and tubing shall furnish with each shipment a report showing the producer identity, co

48、untry where the metal was melted (e.g., final melt in the case of metal processed by multiple melting operations), results of tests for composition, macrostructure and micro-inclusion rating of each heat, and for response to heat treatment of each lot and stating that the product conforms to the oth

49、er technical requirements. This report shall include the purchase order number, heat and lot numbers, AMS6476E, 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 the forgings shall also be included. 4.4.2 Report the nominal metallurgically worked cross sectional size and the cut size, if dif