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 2014 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/AMS6270QAEROSPACE MATERIAL SPECIFICATIONAMS6270 REV. QIssued 1942-09Reaffirmed 2006-02Revised
5、 2014-07Superseding AMS6270PSteel, Bars, Forgings, and Tubing0.50Cr - 0.55Ni - 0.20Mo (0.13 - 0.18C) (SAE 8615)(Composition similar to UNS G86150)RATIONALEAMS6270Q results from a Five Year Review and update of this specification 1. SCOPE1.1 FormThis specification covers an aircraft-quality, low-allo
6、y steel in the form of bars, forgings, mechanical tubing, and forging stock.1.2 ApplicationThese products have been used typically for carburized parts which require low minimum core hardness and allow wide hardness range in sections 0.375 inch (9.52 mm) and under in nominal thickness, but usage is
7、not limited to such applications. The core should be machinable after hardening.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 herein. The supplier may work to a subsequent revision of
8、 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 International, 400 Commonwealth Drive, Warrendale, P
9、A 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 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-Alloy and Carbon SteelsAMS2301 Steel Cleanliness, Aircraft Q
10、uality, Magnetic Particle Inspection ProcedureSAE INTERNATIONAL AMS6270Q Page 2 of 6AMS2370 Quality Assurance Sampling and Testing, Carbon and Low-Alloy Steel, Wrought Products and Forging StockAMS2372 Quality Assurance Sampling and Testing, Carbon and Low-Alloy Steel ForgingsAMS2806 Identification,
11、 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 Steel, Bars and Mechanical Tubing2.2 ASTM PublicationsAvail
12、able from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959,Tel: 610-832-9585, www.astm.org.ASTM A 255 Determining Hardenability of SteelASTM A 370 Mechanical Testing of Steel ProductsASTM E 112 Determining Average Grain SizeASTM E 350 Chemical Analysis of Ca
13、rbon Steel, Low-Alloy Steel, Silicon Electrical Steel, Ingot Iron, and Wrought IronASTM E 381 Macroetch Testing Steel Bars, Billets, Blooms, and Forgings3. TECHNICAL REQUIREMENTS3.1 CompositionShall conform to the percentages by weight shown in Table 1, determined by wet chemical methods in accordan
14、ce with ASTM E 350, by spectrochemical methods, or by other analytical methods acceptable to purchaser.TABLE 1 - COMPOSITIONElement min maxCarbon 0.13 0.18Manganese 0.70 0.90Silicon 0.15 0.35Phosphorus - 0.025Sulfur - 0.025Chromium 0.40 0.60Nickel 0.40 0.70Molybdenum 0.15 0.25Copper - 0.353.1.1 Chec
15、k AnalysisComposition variations shall meet the applicable requirements of AMS2259.3.2 ConditionThe product shall be supplied in the following condition unless another condition is authorized by purchaser; hardness and tensile strength shall be determined in accordance with ASTM A 370:SAE INTERNATIO
16、NAL AMS6270Q Page 3 of 63.2.1 Bars3.2.1.1 Bars 0.500 Inch (12.70 mm) and Under in Nominal Diameter or Least Distance Between Parallel SidesCold finished having tensile strength not higher than 130 ksi (896 MPa) or equivalent hardness (See 8.2).3.2.1.2 Bars Over 0.500 Inch (12.70 mm) in Nominal Diame
17、ter or Least Distance Between Parallel SidesHot finished, unless otherwise ordered, having hardness not higher than 229 HB, or equivalent (See 8.3). Bars ordered cold finished may have hardness as 248 HB, or equivalent (See 8.3).3.2.1.3 Bar shall not be cut from plate (Also see 4.4.2).3.2.2 Forgings
18、As ordered.3.2.3 Mechanical TubingCold finished, unless otherwise ordered, having hardness not higher than 25 HRC, or equivalent (See 8.3). Tubing ordered hot finished shall have hardness not higher than 99 HRB, or equivalent (See 8.3).3.2.4 Forging StockAs ordered by the forging manufacturer.3.3 Pr
19、opertiesThe product shall conform to the following requirements; hardness testing shall be performed in accordance with ASTM A 370:3.3.1 MacrostructureVisual examination of transverse full cross-sections from bars, billets, tube rounds, and forging stock, etched in hot hydrochloric acid in accordanc
20、e with ASTM E 381, shall not show pipe or cracks. Porosity, segregation, inclusions, and other imperfections shall be no worse than the macrographs of ASTM E 381 shown in Table 2.TABLE 2 - MACROSTRUCTURE LIMITSCross Sectional Area Square InchesCross Sectional AreaSquare Centimeters MacrographsUp to
21、36, incl Up to 232, incl S2 - R1 - C2Over 36 to 133, incl Over 232 to 858, incl S2 - R2 - C3Over 133 Over 858 Note 1Note 1 Limits for larger sizes shall be agreed upon by purchaser and vendor. The purchaser shall have written approval of the agreement from the cognizant engineering organization.3.3.
22、2 Average Grain Size of Bar, Forgings, and TubingShall be ASTM No. 5 or finer, determined in accordance with ASTM E 112.3.3.3 Hardenability of Each HeatShall be J1/16 inch (1.6 mm) = 45 HRC maximum and J4/16 inch (6.4 mm) = 20 HRC minimum, determined on the standard end-quench test specimen in accor
23、dance with ASTM A 255, except that the steel shall be normalized at 1750 F 10 (954 C 6) and the test specimen austenitized at 1550 F 10 (843 C 6).SAE INTERNATIONAL AMS6270Q Page 4 of 63.4 QualityThe product, as received by purchaser, shall be uniform in quality and condition, sound, and free from fo
24、reign materials and from imperfections detrimental to usage of the product.3.4.1 Steel shall be aircraft quality conforming to AMS2301.3.4.2 Bars and mechanical tubing ordered hot rolled or cold drawn, or ground, turned, or polished, shall, after removal of the standard stock removal allowance in ac
25、cordance with AS1182, be free from seams, laps, tears, and cracks exposed to the machined, ground, turned, or polished surfaces.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 evidence of reentrant grai
26、n flow.3.5 Tolerances3.5.1 BarsIn accordance with AMS2251.3.5.2 Mechanical TubingIn accordance with to AMS2253.4. QUALITY ASSURANCE PROVISIONS4.1 Responsibility for InspectionThe vendor of the product shall supply all samples for vendors tests and shall be responsible for the performance of all requ
27、ired tests. Purchaser reserves the right to sample and perform any confirmatory testing deemed necessary to ensure that the product conforms to specified requirements.4.2 Classification of Tests4.2.1 Acceptance TestsComposition (3.1), condition (3.2), macrostructure (3.3.1), average grain size (3.3.
28、2), hardenability (3.3.3), frequency-severity cleanliness rating (3.4.1), and tolerances (3.5) are acceptance tests and shall be performed on each heat or lot as applicable.4.2.2 Periodic TestsGrain flow of die forgings (3.4.3) is a periodic test and shall be performed at a frequency selected by the
29、 vendor unless a frequency of testing is specified by purchaser.4.3 Sampling and Testing4.3.1 Bars, Mechanical Tubing, and Forging StockIn accordance with AMS2370.4.3.2 ForgingsIn accordance with AMS2372.SAE INTERNATIONAL AMS6270Q Page 5 of 64.4 Reports4.4.1 The producer of the bar, tubing, and forg
30、ings shall furnish with each shipment a report showing producer identity and 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 chemical composition, macrostructure, hardenability, and frequency-severity clea
31、nliness rating of each heat and for condition and average grain size of 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, AMS6270Q, product form and size or part number, and quantity. If for
32、gings 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 different (See 3.2.1.3).4.4.3 The producer of forging stock shall furnish with each shipment a report showi
33、ng producer identity and country where the metal was melted (e. g., final melt in the case of metal processed by multiple melting operations) and the results of tests for composition, macrostructure, hardenability, and frequency-severity cleanliness rating of each heat. This report shall include the
34、 purchase order number, heat number, AMS6270Q, size and quantity4.5 Resampling and Retesting4.5.1 Bars, Mechanical Tubing, and Forging StockIn accordance with AMS2370.4.5.2 ForgingsIn accordance with AMS2372.5. PREPARATION FOR DELIVERY5.1 SizesExcept when exact lengths or multiples of exact lengths
35、are ordered, straight bars and mechanical 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 lengthsshorter than 10 feet (3 m).5.2 Identification5.2.1 Bars and Mechanical TubingIn accordance with AMS2806.5.2.2 Forgings
36、In accordance with AMS2808.5.2.3 Forging StockAs agreed upon by purchaser and vendor.5.3 Protective TreatmentBars and mechanical tubing ordered cold drawn, cold rolled, ground, turned, or polished shall be protected from corrosion prior to shipment.SAE INTERNATIONAL AMS6270Q Page 6 of 65.4 Packaging
37、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 product to ensure carrier acceptance and safe delivery.6. ACKNOWLEDGMENTA vendor shall include th
38、is specification number and its revision letter in all quotations and when acknowledging purchase orders.7. REJECTIONProduct not conforming to this specification, or to modifications authorized by purchaser, will be subject to rejection.8. NOTES8.1 A change bar (l) located in the left margin is for
39、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 indicates a complete revision of the document, including technical revisions. Change bars and (R) are
40、 not used in original publications, nor in documents that contain editorial changes only.8.2 Tensile strength to hardness conversions are presented in ASTM A 370.8.3 Hardness conversion tables for metals are presented in ASTM E 140.8.4 Terms used in AMS are clarified in ARP1917.8.5 Dimensions and pr
41、operties 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.8.6 Purchase documents should specify not less than the following:AMS6270QProduct form and size or part number of product desiredQuantity of product desired.PREPARED BY AMS COMMITTEE “E”
