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/AMS6280M AEROSPACE MATERIAL SPECIFICATION AMS6280 REV. M Issued 1942-09 Revised 2017-08 Supers
5、eding AMS6280L Steel Bars, Forgings, and Rings 0.50Cr - 0.55Ni - 0.20Mo (0.28 - 0.33C) (SAE 8630) (Composition similar to UNS G86300) RATIONALE AMS6280M results from a Five-Year Review and update of this specification that revises grain size determination (3.1.1 and 3.3.2), decarburization determina
6、tion (3.3.4), surface quality (3.4.2), testing frequency (4.2), reporting (4.4) and identification (5.2). 1. SCOPE 1.1 Form This specification covers an aircraft-quality, low-alloy steel in the form of bars, forgings, flash welded rings, and stock for forging or flash welded rings. 1.2 Application T
7、hese products have been used typically for parts, with sections 0.500 inch (12.70 mm) and under in thickness at time of heat treatment, requiring a through-hardening steel capable of developing hardness as high as 35 HRC when properly hardened and tempered and also for parts of greater thickness but
8、 requiring proportionately lower hardness, but usage is not limited to such applications. 2. APPLICABLE DOCUMENTS The following publications form a part of this document to the extent specified herein. The latest issue of SAE publications shall apply. The applicable issue of other publications shall
9、 be the issue in effect on the date of the purchase order. In the event of conflict between the text of this document and references cited herein, the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has
10、 been obtained. 2.1 SAE Publications Available from SAE 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 Bars AMS2259 Chemical Check Analysis Limits Wrought Lo
11、w-Alloy and Carbon Steels SAE INTERNATIONAL AMS6280M Page 2 of 8 AMS2301 Steel Cleanliness, Aircraft Quality Magnetic Particle Inspection Procedure AMS2370 Quality Assurance Sampling and Testing Carbon and Low-Alloy Steel Wrought Products and Forging Stock AMS2372 Quality Assurance Sampling and Test
12、ing Carbon and Low-Alloy Steel Forgings AMS2806 Identification Bars, Wire, Mechanical Tubing, and Extrusions Carbon and Alloy Steels and Corrosion and Heat-Resistant Steels and Alloys AMS2808 Identification Forgings AMS7496 Rings, Flash Welded, Carbon and Low-Alloy Steels ARP1917 Clarification of Te
13、rms Used in Aerospace 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
14、-832-9585, www.astm.org. ASTM A255 Determining the Hardenability of Steel ASTM A370 Mechanical Testing of Steel Products ASTM E112 Determining Average Grain Size ASTM E140 Hardness Conversion Tables for Metals Relationship Among Brinell Hardness, Vickers Hardness, Rockwell Hardness, Superficial Hard
15、ness, Knoop Hardness, Scleroscope 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
16、. 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 E350, by spectrochemical methods, or by other analytical methods acceptable to purchaser. Table 1 - Composition Element Min Max Carbon 0.28
17、 0.33 Manganese 0.70 0.90 Silicon 0.15 0.35 Phosphorus - 0.025 Sulfur - 0.025 Chromium 0.40 0.60 Nickel 0.40 0.70 Molybdenum 0.15 0.25 Copper - 0.35 SAE INTERNATIONAL AMS6280M Page 3 of 8 3.1.1 Aluminum, vanadium and columbium are optional grain refining elements and need not be determined or report
18、ed unless used to satisfy the average grain size requirements of 3.3.2.2. 3.1.2 Check Analysis Composition variations shall meet the applicable requirements of AMS2259. 3.2 Condition The product shall be supplied in the following condition; hardness and tensile strength shall be determined in accord
19、ance 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 having tensile strength not higher than 125 ksi (862 MPa) or hardness not higher than 26 HRC. 3.2.
20、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 hardness not higher than 229 HB, or equivalent (see 8.2). Bars ordered cold finished may have hardness as high as 248 HB, or equivalent (see 8.
21、2). 3.2.2 Forgings and Flash Welded Rings As ordered. 3.2.2.1 Flash welded rings shall not be supplied unless specified or permitted on purchasers part drawing. When supplied, flash welded rings shall be manufactured in accordance with AMS7496. 3.2.3 Stock for Forging or Flash Welded Rings As ordere
22、d by the forging or flash welded ring manufacturer. 3.3 Properties The product shall conform to the following 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, and stock for fo
23、rging or flash welded rings, 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 macrographs of ASTM E381 shown in Table 2. Table 2 - Macrostructure limits Cross-Sectional Ar
24、ea 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 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 wri
25、tten approval of the agreement from the cognizant engineering organization. SAE INTERNATIONAL AMS6280M Page 4 of 8 3.3.2 Average Grain Size of Bars, Forgings, and Flat Welded Rings 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 i
26、n accordance with ASTM E112. 3.3.2.2 The product of a heat shall be considered to have an ASTM No. 5 or 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 con
27、tent 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 0.02 to 0.05%. 3.3.3 Hardenability of Each Heat Shall be J5/16 inch (7.9 mm) = 35 HRC minimum and J8/16 inch (12.7 mm) = 28 HRC minimum, determined on the standard end-quench test specimen in acc
28、ordance 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 1525 F 10 F (829 C 6 C). 3.3.4 Decarburization 3.3.4.1 Bars and flash welded rings ordered ground, turned, or polished shall be free from decarburization on the ground, t
29、urned, or polished surfaces. 3.3.4.2 Allowable decarburization of bars and billets ordered for redrawing or forging or to specified microstructural requirements shall be as agreed upon by purchaser and producer. 3.3.4.3 Decarburization of bars and flash welded rings that 3.3.4.1 or 3.3.4.2 is not ap
30、plicable shall be not greater than shown in Table 3. Table 3 Table 3A - Maximum depth of decarburization limits, inch/pound units Nominal Diameter or Distance Between Parallel Sides Inches Total Depth of Decarburization, Inch Up to 0.375, incl 0.010 Over 0.375 to 0.500, incl 0.012 Over 0.500 to 0.62
31、5, incl 0.014 Over 0.625 to 1.000, incl 0.017 Over 1.000 to 1.500, incl 0.020 Over 1.500 to 2.000, incl 0.025 Over 2.000 to 2.500, incl 0.030 Over 2.500 to 3.000, incl 0.035 Over 3.000 to 4.000, incl 0.045 SAE INTERNATIONAL AMS6280M Page 5 of 8 Table 3B - Maximum depth of decarburization limits, SI
32、units Nominal Diameter or Distance Between Parallel Sides Millimeters Total Depth of Decarburization, Millimeters Up to 9.52, incl 0.25 Over 9.52 to 12.70, incl 0.30 Over 12.70 to 15.88, incl 0.36 Over 15.88 to 25.40, incl 0.43 Over 25.40 to 38.10, incl 0.51 Over 38.10 to 50.80, incl 0.64 Over 50.80
33、 to 63.50, incl 0.76 Over 63.50 to 76.20, incl 0.89 Over 76.20 to 101.60, incl 1.14 3.3.4.3.1 When permitted by purchaser, flash welded rings, to be machined all over by purchaser, may have decarburization greater than shown in Table 3 provided such decarburization is removable within the machining
34、allowance for the part. 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, selected at the discretion of the producer. 3.3.4.4.1 Metallographic Method A cross section taken perpendicular to the surface shall be prepared, etched, and visually examined meta
35、llographically at a magnification not to exceed 100X. 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 microindenta
36、tion hardness testing in accordance with ASTM E384, 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
37、to the depth 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. 3.3.4.4.3 When determining the depth of d
38、ecarburization, 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. 3.3.4.4.4 In case of dispute, the total depth of decarburization determined using th
39、e microindentation hardness traverse method shall govern. 3.4 Quality The 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. 3.4.1 Steel shall be aircraft-quality conforming
40、to AMS2301. 3.4.2 Bars shall be free from seams, laps, tears, and cracks after removal of the standard stock removal allowance in accordance with AS1182. 3.4.3 Grain flow of die forgings, except in areas which contain flash-line end grain, shall follow the general contour of the forgings showing no
41、evidence of reentrant grain flow. SAE INTERNATIONAL AMS6280M Page 6 of 8 3.5 Tolerances Bars shall conform to all applicable requirements of AMS2251. 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for Inspection The producer of the product shall supply all samples for producers tests and shall b
42、e 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 product conforms to specified requirements. 4.2 Classification of Tests 4.2.1 Acceptance Tests Composition (3.1), hardness (3.2.
43、1), macrostructure (3.3.1), average grain size (3.3.2), hardenability (3.3.3), decarburization (3.3.4), frequency-severity cleanliness ratings (3.4.1), and tolerances (3.5) are acceptance tests and shall be performed on each heat or lot as applicable. If grain refining elements (3.3.2.2) are not pre
44、sent, the ASTM E112 grain size test (3.3.2.1) shall be conducted on each lot. 4.2.2 Periodic Tests Grain flow of die forgings is a periodic test and shall be performed at a frequency selected by the producer unless frequency of testing is specified by the purchaser. If grain refining elements (3.3.2
45、.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 4.3.1 Bars, Flash Welded Rings, Forg
46、ing Stock, and Stock for Flash Welded Rings In accordance with AMS2370. 4.3.2 Forgings In accordance with AMS2372. 4.4 Reports 4.4.1 The producer of bars, forgings and flash welded rings shall furnish with each shipment a report showing producer identity, country where the metal was melted (e.g., fi
47、nal melt in the case of metal processed by multiple melting operations), the results of composition, macrostructure, hardenability and frequency-severity cleanliness rating for each heat and for average grain size of each lot and stating that the product conforms to other technical requirements. Thi
48、s report shall include the purchase order number, heat and lot numbers, AMS6280M, product form, 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. If the grain size requirement of 3.3.
49、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 If the ship size/shape is cut from a larger cross section, report the nominal metallurgically worked size (see 3.2.1). 4.4.3 The producer of stock for forging and flash welded rings shall furnish
