1、AEROSPACE MATERIAL SPECIFICATION AMS4920 REV. F Issued 1984-07 Revised 2015-02 Superseding AMS4920E Titanium Alloy, Forgings 6AI - 4V Alpha-Beta or Beta Processed, Annealed (Composition similar to UNS R56400) RATIONALE AMS4920F results from a Five Year Review and update of this specification that in
2、cludes the removal of sample size allowance for hydrogen of Table 1 (covered by ASTM E1447) and allowance of higher hyrdrogen for forgings, requires agreement on mechanical property values for material outside specification ranges (3.5.1.1.1 and 8.7), the addition of AS6279 (3.7) and revises the rep
3、ort paragraph (4.4). 1. SCOPE 1.1 Form This specification covers a titanium alloy in the form of forgings, 6.000 inches (152.40 mm) and under in cross-sectional thickness and forging stock of any size. 1.2 Application These forgings have been used typically for parts that do not require heat treatme
4、nt but require high mechanical properties in the annealed condition and for which processing above the beta transus is permissible, but usage is not limited to such applications. This alloy exhibits high strength-to-weight ratios up to 750 F (399 C). 1.2.1 Certain processing procedures and service c
5、onditions may cause these products to become subject to stress-corrosion cracking; ARP982 recommends practices to minimize such conditions. 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 specif
6、ied herein. The supplier may 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. _ SAE Technical Standards Boa
7、rd 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 therefrom, is the sole responsibil
8、ity 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 2015 SAE International All rights reserved. No part of this publication may be reproduced,
9、 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 (outside USA) Fax: 724-776-
10、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/AMS4920F SAE INTERNATIONAL AMS4920F Page 2 of 6 2.1 SAE Publications Available from SAE International, 400 Com
11、monwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org. AMS2249 Chemical Check Analysis Limits, Titanium and Titanium Alloys AMS2750 Pyrometry AMS2808 Identification, Forgings ARP982 Minimizing Stress-Corrosion Cracking in Wro
12、ught Titanium Alloy Products AS6279 Industry Standard Practices for Production, Distribution, and Procurement of Metal Stock 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 E8 / E8M
13、 Tension Testing of Metallic Materials ASTM E539 Analysis of Titanium Alloys by X-Ray Fluorescence Spectrometry ASTM E1409 Determination of Oxygen and Nitrogen in Titanium and Titanium Alloys by the Inert Gas Fusion Technique ASTM E1447 Determination of Hydrogen in Titanium and Titanium Alloys by th
14、e Inert Gas Fusion Thermal Conductivity/Infrared Detection Method ASTM E1941 Determination of Carbon in Refractory and Reactive Metals and Their Alloys by Combustion Analysis ASTM E2371 Analysis of Titanium and Titanium Alloys by Direct Current Plasma and Inductively Coupled Plasma Atomic Emission S
15、pectrometry 3. TECHNICAL REQUIREMENTS 3.1 Composition Shall conform to the percentages by weight shown in Table 1; carbon shall be determined in accordance with ASTM E1941, hydrogen in accordance with ASTM E1447, oxygen and nitrogen in accordance with ASTM E1409, and other elements in accordance wit
16、h ASTM E539 or ASTM E2371. Other analytical methods may be used if acceptable to the purchaser. Table 1 - Composition Element min max Aluminum 5.50 6.75 Vanadium 3.50 4.50 Iron - 0.30 Oxygen - 0.20 Carbon - 0.10 Nitrogen - 0.05 (500 ppm) Hydrogen - 0.0125 (125 ppm) Yttrium (3.1.3) - 0.005 ( 50 ppm)
17、Other Elements, each (3.1.1) - 0.10 Other Elements, total (3.1.1) - 0.40 Titanium remainder SAE INTERNATIONAL AMS4920F Page 3 of 6 3.1.1 Determination not required for routine acceptance. 3.1.2 Check Analysis Composition variations shall meet the applicable requirements of AMS2249. Variation over ma
18、ximum is not permitted for yttrium. 3.2 Melting Practice Alloy shall be multiple melted. The first melt shall be made by vacuum consumable electrode, nonconsumable electrode, electron beam cold hearth, or plasma arc cold hearth melting practice. The subsequent melt or melts shall be made under vacuu
19、m using vacuum arc remelting (VAR) practice. Alloy additions are not permitted in the final melt cycle. 3.2.1 The atmosphere for nonconsumable electrode melting shall be vacuum or shall be argon and/or helium at an absolute pressure not higher than 1000 mm of mercury. 3.2.2 The electrode tip for non
20、consumable electrode melting shall be water-cooled copper. 3.3 Condition The product shall be supplied in the following condition: 3.3.1 Forgings Annealed and descaled. 3.3.2 Forging Stock As ordered by the forging manufacturer. 3.4 Annealing Forgings shall be annealed by heating to a temperature wi
21、thin the range 1300 to 1400 F (704 to 760 C), holding at the selected temperature within 25 F (14 C) for a time commensurate with section thickness and the heating equipment and procedure used, and cooling at a rate that will produce forgings meeting the requirements of 3.5.1. Pyrometry shall be in
22、accordance with AMS2750. 3.5 Properties The product shall conform to the following requirements: 3.5.1 Forgings 3.5.1.1 Tensile Properties Forgings, 6.000 inches (152.40 mm) and under in cross-sectional thickness, shall have the properties shown in Table 2, determined in accordance with ASTM E8 / E8
23、M on specimens as in 4.3.1.2 with the rate of strain set at 0.005 inch/inch/minute (0.005 mm/mm/minute) and maintained within a tolerance of 0.002 inch/inch/minute (0.002 mm/mm/minute) through the 0.2% offset yield strain. Table 2 - Minimum tensile properties Property Value Tensile Strength 130 ksi
24、(896 MPa) Yield Strength at 0.2% Offset 120 ksi (827 MPa) Elongation in 4D 8% Reduction of Area 15% 3.5.1.1.1 Mechanical property requirements for product outside the range covered by 3.5.1.1 shall be agreed upon between purchaser and producer. SAE INTERNATIONAL AMS4920F Page 4 of 6 3.5.1.2 Microstr
25、ucture Shall be that structure resulting from alpha-beta or beta processing, as specified by purchaser (See 8.7). When no structure is specified, alpha-beta processing shall be performed. Standards for acceptance shall be as agreed upon by purchaser and producer. 3.5.1.3 Surface Contamination Except
26、 as permitted by 3.5.1.3.1, forgings shall be free of any oxygen-rich layer (See 8.2), such as alpha case, or other surface contamination, determined by microscopic examination at not lower than 400X magnification or by other method acceptable to purchaser. 3.5.1.3.1 When permitted by purchaser, for
27、gings to be machined all over may have an oxygen-rich layer provided such layer is removable within the machining allowance on the forging. 3.5.2 Forging Stock When a sample of stock is forged to a test coupon and heat treated as in 3.4, specimens taken from the heat treated coupon shall conform to
28、the requirements of 3.5.1.1. If specimens taken from the stock after heat treatment as in 3.4 conform to the requirements of 3.5.1.1, the tests shall be accepted as equivalent to tests of a forged coupon. 3.6 Quality The product, as received by purchaser, shall be uniform in quality and condition, s
29、ound, and free from foreign materials and from imperfections detrimental to usage of the product. 3.6.1 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 grain flow. 3.7 Production, distri
30、bution, and procurement of metal stock shall comply with AS6279. This requirement becomes effective August 01, 2016. 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
31、 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 The following requirements are acceptance tests and shall be perfo
32、rmed on each heat or lot as applicable: 4.2.1.1 Composition (3.1) of each heat. 4.2.1.2 Hydrogen content (3.1), tensile properties (3.5.1.1), microstructure (3.5.1.2), and surface contamination (3.5.1.3) of each lot of forgings. 4.2.2 Periodic Tests Tests for ability of forging stock to develop requ
33、ired properties (3.5.2) are periodic tests and shall be performed at a frequency selected by the producer unless frequency of testing is specified by purchaser. SAE INTERNATIONAL AMS4920F Page 5 of 6 4.3 Sampling and Testing Shall be in accordance with the following; a lot shall be all product of th
34、e same part number from the same heat, processed at the same time, and annealed in the same heat treat batch. 4.3.1 For Acceptance Tests 4.3.1.1 Composition One sample from each heat, except for hydrogen determinations one sample from each lot obtained after thermal and chemical processing has been
35、completed. 4.3.1.2 Tensile Properties One or more specimens from each lot of forgings. The location and orientation of the specimen, and the number of any additional specimens, shall be as agreed upon between purchaser and producer. 4.3.1.3 Microstructure and Surface Contamination One or more sample
36、s from each lot. 4.4 Reports 4.4.1 The producer shall furnish with each shipment a report showing producer identity, country where the metal was melted (i.e., final melt in the case of metal processed by multiple melting operations), the results of tests for composition of each heat and for the hydr
37、ogen content and tensile properties of each lot, and stating that the forgings conform to the other technical requirements. This report shall include the purchase order number, heat and lot numbers, AMS4920F, product form and size (and/or part number, if applicable), specific annealing treatment use
38、d, and quantity. The size and melt source of stock used to make the forgings shall also be included. The producer of forging stock shall furnish with each shipment a report showing the results of tests for chemical composition of each heat and for the hydrogen content of each lot. This report shall
39、include the purchase order number, heat number, AMS4920F, size, and quantity. 4.4.2 Report the nominal metallurgically worked cross sectional size and the cut size, if different. 4.4.3 When the product size is outside the range covered by 3.5.1.1.1, the report shall contain a statement to that effec
40、t. 4.5 Resampling and Retesting If any specimen used in the above tests fails to meet the specified requirements, disposition of the product may be based on the results of testing three additional specimens for each original nonconforming specimen. Failure of any retest specimen to meet specified re
41、quirements shall be cause for rejection of the product represented. Results of all tests shall be reported. 5. PREPARATION FOR DELIVERY 5.1 Identification 5.1.1 Forgings In accordance with AMS2808, except that characters shall be applied using a marking fluid whose residue shall contain not more tha
42、n traces of halogen bearing compounds. 5.1.2 Forging Stock As agreed upon by purchaser and producer. SAE INTERNATIONAL AMS4920F Page 6 of 6 5.2 Packaging The product shall be prepared for shipment in accordance with commercial practice and in compliance with applicable rules and regulations pertaini
43、ng to the handling, packaging, and transportation of the product to ensure carrier 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 Product not conforming
44、 to this specification, or to modifications authorized by purchaser, will be subject to rejection. 8. NOTES 8.1 A change bar (l) 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 t
45、his 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 not used in original publications, nor in documents that contain editorial changes only. 8.2 An oxygen-rich layer, such as alpha case, i
46、s hard and brittle and results in marked lowering of fatigue properties. 8.3 Mechanical design properties for this specification are included in MMPDS. 8.4 Terminology for titanium microstructures is presented in AS1814. 8.5 Terms used in AMS are clarified in ARP1917. 8.6 Dimensions and properties i
47、n 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. 8.7 Purchase documents should specify not less than the following:
48、AMS4920F Product form and size (and/or part number, if applicable) of product desired Quantity of product desired Acceptance standards for microstructure (3.5.1.2) Alpha-beta or beta processing (3.5.1.2) Property and acceptance requirements from the cognizant engineering organization applicable to sizes outside the size range listed in 1.1. PREPARED BY AMS COMMITTEE “G”
