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 ther
2、efrom, 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 2017 SAE International All rights reserved. No part of this
3、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) Tel: +1 724-776-49
4、70 (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:/standards.sae.org/AMS6381J AEROSPACE MATERIAL SPECIFICATION AMS6381 REV. J Issued 1942-12 Reaffirmed 2008-04 Rev
5、ised 2017-10 Superseding AMS6380H Steel, Mechanical Tubing 0.95Cr - 0.20Mo (0.38 - 0.43C) (SAE 4140) (Composition similar to UNS G41400) RATIONALE AMS6381J results from a Five-Year Review and update of this specification that revises grain size determination (3.1.1 and 3.3.2), decarburization determ
6、ination (3.3.4.4), quality (3.4.2), testing frequency (4.2, reporting (4.4) and identification (5.2.1). 1. SCOPE 1.1 Form This specification covers an aircraft-quality, low-alloy steel in the form of mechanical tubing. 1.2 Application This tubing has been used typically for parts, 0.500 inch (12.70
7、mm) and under in nominal wall thickness at time of heat treatment requiring a through-hardening steel capable of developing hardness as high as 50 HRC when properly hardened and tempered and also for parts of greater wall thickness but requiring proportionately lower hardness, but usage is not limit
8、ed 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 may work to a subsequent revision of a document unless a specific document issue is specif
9、ied. 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 Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Cana
10、da) or +1 724-776-4970 (outside USA), www.sae.org. AMS2253 Tolerances, Carbon and Alloy Steel Tubing AMS2259 Chemical Check Analysis Limits Wrought Low-Alloy and Carbon Steels AMS2301 Steel Cleanliness, Aircraft Quality Magnetic Particle Inspection Procedure SAE INTERNATIONAL AMS6381J Page 2 of 6 AM
11、S2370 Quality Assurance Sampling and Testing, Carbon and Low-Alloy Steel Wrought Products and Forging Stock AMS2806 Identification Bars, Wire, Mechanical Tubing, and Extrusions Carbon and Alloy Steels and Corrosion and Heat-Resistant Steels and Alloys ARP1917 Clarification of Terms Used in Aerospace
12、 Metals Specifications 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 Conshohocken, PA 19428-2959, Tel: 610-832-9585, www.astm.o
13、rg. ASTM A255 Determining Hardenability of Steel ASTM E18 Rockwell Hardness of Metallic Materials ASTM E112 Determining Average Grain Size ASTM E140 Hardness Conversion Tables for Metals Relationship Among Brinell Hardness, Vickers Hardness, Rockwell Hardness, Superficial Hardness, Knoop Hardness, S
14、cleroscope Hardness, and Leeb Hardness 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 of Materials 3. TECHNICAL REQUIREMENTS
15、 3.1 Composition Shall 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 0.38 0.43 Manganese 0.75 1.00
16、Silicon 0.15 0.35 Phosphorus - 0.025 Sulfur - 0.025 Chromium 0.80 1.10 Molybdenum 0.15 0.25 Nickel - 0.25 Copper - 0.35 3.1.1 Aluminum, vanadium and columbium are optional grain refining elements and need not be determined or reported unless used to satisfy the average grain size requirements of 3.3
17、.2.2. 3.1.2 Check Analysis Composition variations shall meet the applicable requirements of AMS2259. SAE INTERNATIONAL AMS6381J Page 3 of 6 3.2 Condition Cold finished, unless otherwise ordered, having hardness not higher than 25 HRC, or equivalent (see 8.2). Tubing ordered hot finished and annealed
18、 or tempered shall have hardness not higher than 99 HRB, or equivalent (see 8.2). Hardness shall be determined in accordance with ASTM E18. 3.3 Properties Tubing shall conform to the following requirements. 3.3.1 Macrostructure Visual examination of transverse full cross-sections from blooms or tube
19、 rounds (not hollows), 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 macrographs of ASTM E381 shown in Table 2. Table 2 - Macrostructure limits Section Size Square Inches S
20、ection Size Square Centimeters Macrographs Up to 36, incl Up to 232, incl S2 - R1 - C2 Over 36 to 133, incl Over 232 to 858, incl S2 - R2 - C3 Over 133 Over 858 Note 1 Note 1: Limits for larger sizes shall be agreed upon by purchaser and producer. The purchaser shall have written approval of the agr
21、eement from the cognizant engineering organization. 3.3.2 Average Grain Size Average grain size shall be determined by either 3.3.2.1 or 3.3.2.2. 3.3.2.1 Shall be ASTM No. 5 or finer, determined in accordance with ASTM E112. 3.3.2.2 The product of a heat shall be considered to have an ASTM No. 5 or
22、finer austenitic grain size if one or more of the following are determined by heat analysis (see 8.5): 3.3.2.2.1 A total aluminum content of 0.020 to 0.050%. 3.3.2.2.2 An acid soluble aluminum content of 0.015 to 0.050%. 3.3.2.2.3 A vanadium content of 0.02 to 0.08%. 3.3.2.2.4 A columbium content of
23、 0.02 to 0.05%. 3.3.3 Hardenability of Each Heat Shall be J 6/16 inch (9.5 mm) = 50 HRC minimum, determined on the standard end-quench test specimen in accordance with ASTM A255 except that the steel shall be normalized at 1700 F 10 F (927 C 6 C) and the test specimen austenitized at 1550 F 10 F (84
24、3 C 6 C). 3.3.4 Decarburization 3.3.4.1 Tubing ordered ground, turned, or polished shall be free from decarburization on the ground, turned, or polished surfaces. 3.3.4.2 Allowable decarburization of pierced billets, of tube rounds, and tubing for redrawing or forging, or of tubing ordered to specif
25、ied microstructural requirements shall be as agreed upon by purchaser and producer. SAE INTERNATIONAL AMS6381J Page 4 of 6 3.3.4.3 Decarburization of tubing that 3.3.4.1 or 3.3.4.2 is not applicable shall be not greater than shown in Table 3. Table 3 Table 3A - Maximum depth of decarburization, inch
26、/pound units Nominal Wall Thickness Inches Total Depth ID Inch Total Depth OD Inch Up to 0.109, incl 0.008 0.015 Over 0.109 to 0.203, incl 0.010 0.020 Over 0.203 to 0.400, incl 0.012 0.025 Over 0.400 to 0.600, incl 0.015 0.030 Over 0.600 to 1.000, incl 0.017 0.035 Over 1.000 0.020 0.040 Table 3B - M
27、aximum depth of decarburization, SI units Nominal Wall Thickness Millimeters Total Depth ID Millimeter Total Depth OD Millimeter Up to 2.77, incl 0.20 0.38 Over 2.77 to 5.16, incl 0.25 0.51 Over 5.16 to 10.16, incl 0.30 0.64 Over 10.16 to 15.24, incl 0.38 0.76 Over 15.24 to 25.40, incl 0.43 0.89 Ove
28、r 25.40 0.51 1.02 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. 3.3.4.4.1 Metallographic Method A cross section taken perpendicular to the surface shall be prepared, etched, and visually examined metallographically at a magnification not to exceed 10
29、0X. The product shall not show a layer of complete (ferrite) or partial decarburization exceeding the limits of Table 3. 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
30、, at a magnification not exceeding 100X, conducted on a hardened but untempered specimen 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
31、 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. 3.3.4.4.3 When determining the depth of decarburization, it is permissible to disregard loc
32、al 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. 3.3.4.4.4 In case of dispute, the total depth of decarburization determined using the microindentation hardness traverse method shall
33、govern. 3.4 Quality Tubing, 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 tubing. SAE INTERNATIONAL AMS6381J Page 5 of 6 3.4.1 Steel shall be aircraft quality conforming to AMS2301. 3.4.2
34、 Mechanical tubing shall, be free from seams, laps, tears, and cracks after removal of the standard stock removal allowance in accordance with AS1182. 3.5 Tolerances Shall conform to all applicable requirements of AMS2253. 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for Inspection The produce
35、r of the tubing 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 ensure that the tubing conforms to specified requirements. 4.2 Classific
36、ation of Tests 4.2.1 Acceptance Tests All technical requirements are acceptance tests and shall be performed on each heat or lot as applicable. If grain refining elements (3.3.2.2) are not present, the ASTM E112 grain size test (3.3.2.1) shall be conducted on each lot. 4.2.2 Periodic Tests If grain
37、refining elements (3.3.2.2) are present, the ASTM E112 grain size test (3.3.2.1) shall be conducted on a periodic basis and shall be performed at a frequency selected by the producer (not to exceed one year) unless frequency of testing is specified by purchaser. 4.3 Sampling and Testing In accordanc
38、e with AMS2370. 4.4 Reports 4.4.1 The producer of the product shall furnish 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
39、, hardenability, and frequency-severity cleanliness rating of each heat and for hardness and average grain size (if measured) for 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, AMS6381J, s
40、ize, and quantity. If the grain size requirement of 3.3.2 is met by the aluminum, vanadium and/or columbium content, the aluminum, vanadium and/or columbium content shall be reported and a statement that the chemistry satisfies the grain size requirement shall be included. 4.4.2 When material produc
41、ed to this specification has exceptions taken to the technical requirements listed in Section 3, (see 5.2.1), the report shall contain a statement “This material is certified as AMS6381J(EXC) because of the following exceptions:“ and the specific exceptions shall be listed. 4.5 Resampling and Retest
42、ing In accordance with AMS2370. 5. PREPARATION FOR DELIVERY 5.1 Sizes Except when exact lengths or multiples of exact lengths are ordered, straight 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 shipment shall be supplied in lengths shorter tha
43、n 10 feet (3 m). SAE INTERNATIONAL AMS6381J Page 6 of 6 5.2 Identification In accordance with AMS2806. 5.2.1 When technical exceptions are taken (see 4.4.2), the material shall be marked with AMS6381J(EXC). 5.3 Protective Treatment Mechanical tubing ordered cold drawn, cold rolled, ground, turned, o
44、r polished shall be protected from corrosion prior to shipment. 5.4 Packaging Tubing 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 tubing to ensure carrier
45、 acceptance and safe delivery. 6. ACKNOWLEDGMENT A producer shall include this specification number and its revision letter in all quotations and when acknowledging purchase orders. 7. REJECTIONS Tubing not conforming to this specification, or to modifications authorized by purchaser, will be subjec
46、t to rejection. 8. NOTES 8.1 Revision Indicator A change bar (I) 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) symbol to the left of the document title in
47、dicates 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 E140. 8.3 Terms used in AMS are clarified in AR
48、P1917. 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 information. 8.5 Procurement documents sho
49、uld specify not less than the following: AMS6381J Size of tubing desired Quantity of tubing desired 8.6 Grain size The average grain size resulting from using the appropriate test procedures per ASTM E112 will satisfy an ASTM No. 5 or finer grain size when the elements defined in 3.3.2.2 as grain refiners are present. Other technical societies have adopted the verification of fine grain steel based on chemistry a
