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 2017 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:/standards.sae.org/AS7460C AEROSPACE STANDARD AS7460 REV. C Issued 1992-06 Reaffirmed 2004-07 Revised 2017-04 Supe
5、rseding AS7460B Bolts and Screws, Titanium Alloy 6.0Al - 4.0V Procurement Specification For FSC 5306 RATIONALE Hydrogen test requirement added to lot acceptance Table 3, Figures 1 to 7 redrawn. 1. SCOPE 1.1 Type This procurement specification covers aircraft-quality bolts and screws made of 6.0Al -
6、4.0V titanium alloy and of 160 ksi tensile strength at room temperature. 1.2 Application Primarily for aerospace propulsion system applications where high strength, light weight fasteners are required for use up to approximately 600 F. 1.3 Safety - Hazardous Materials While the materials, methods, a
7、pplications, and processes described or referenced in this specification may involve the use of hazardous materials, this specification does not address the hazards which may be involved in such use. It is the sole responsibility of the user to ensure familiarity with the safe and proper use of any
8、hazardous materials and to take necessary precautionary measures to ensure the health and safety of all personnel involved. 2. REFERENCES 2.1 Applicable Documents The following publications form a part of this document to the extent specified herein. The latest issue of SAE publications shall apply.
9、 The applicable issue of other publications shall 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 law
10、s and regulations unless a specific exemption has been obtained. SAE INTERNATIONAL AS7460C Page 2 of 19 2.1.1 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.
11、 AMS2750 Pyrometry AMS4967 Titanium Alloy, Bars, Wire, Forgings, and Rings 6.0Al - 4.0V Annealed, Heat Treatable AS1132 Bolts, Screws and Nuts - External Wrenching UNJ Thread, Inch - Design Standard AS1814 Terminology for Titanium Microstructures AS3062 Bolts, Screws, and Studs, Screw Thread Require
12、ments AS3063 Bolts, Screws, and Studs, Geometric Control Requirements AS8879 Screw Threads - UNJ Profile, Inch Controlled Radius Root with Increased Minor Diameter 2.1.2 U.S. Government Publications Copies of these documents are available online at http:/quicksearch.dla.mil. MIL-STD-2073-1 Standard
13、Practice for Military Packaging 2.1.3 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 B600 Descaling and Cleaning Titanium and Titanium Alloy Surfaces ASTM E8/E8M Tension Testing of Met
14、allic Materials ASTM E340 Standard Test Method for Macroetching Metals and Alloys ASTM E407 Standard Test Practice for Microetching Metals and Alloys ASTM E1417/E1417M Standard Practice for Liquid Penetrant Testing ASTM E1447 Standard Test Method for Determination of Hydrogen in Titanium and Titaniu
15、m Alloys, by Inert Gas Fusion Thermal Conductivity/Infrared Detection Method 2.1.4 ASME Publications Available from ASME, P.O. Box 2900, 22 Law Drive, Fairfield, NJ 07007-2900, Tel: 800-843-2763 (U.S./Canada), 001-800-843-2763 (Mexico), 973-882-1170 (outside North America), www.asme.org. ASME B46.1
16、Surface Texture (Surface Roughness, Waviness, and Lay) 2.1.5 AIA Publications Available from Aerospace Industries Association, 1000 Wilson Boulevard, Suite 1700, Arlington, VA 22209-3928, Tel: 703-358-1000, www.aia-aerospace.org. NASM1312-6 Fastener Test Methods, Method 6, Hardness NASM1312-8 Fasten
17、er Test Methods, Method 8, Tensile Testing SAE INTERNATIONAL AS7460C Page 3 of 19 2.2 Definitions BURR: A rough edge or ridge left on the metal due to a cutting, grinding, piercing, or blanking operation. COLD ROLLING: Forming material below the recrystallization temperature. CRACK: Rupture in the m
18、aterial which may extend in any direction and which may be intercrystalline or transcrystalline in character. DEFECT: Any nonconformance of the unit of product with specified requirements. DEFECTIVE: A unit of product which contains one or more defects. DISCONTINUITY: An interruption in the normal p
19、hysical structure or configuration of a part; such as a lap, seam, inclusion, crack, machining tear, or stringer. INCLUSION: Non-metallic particles originating from the material making process. They may exist as discrete particles or strings of particles extending longitudinally. LAP: Surface imperf
20、ection caused by folding over metal fins or sharp corners and then rolling or forging them into the surface. The allowable lap depth shall not exceed the limit specified herein. The minimum condition that shall be rated as a lap is a fold having its length equal to or greater than three times its wi
21、dth with a depth of 0.0005 inch when viewed at 200X magnification. MACHINING TEAR: A pattern of short, jagged individual cracks, generally at right angles to the direction of machining, frequently the result of improperly set cutting tools, or dull cutting tools. PRODUCTION INSPECTION LOT: Shall be
22、all finished parts of the same part number, made from a single heat of alloy, heat treated at the same time to the same specified condition, produced as one continuous run, and submitted for manufacturers inspection at the same time. SEAM: Longitudinal surface imperfection in the form of an unwelded
23、, open fold in the material. STRINGER: A solid non-metallic impurity in the metal bar, often the result of inclusions that have been extended during the rolling process. TIGHT BURR: A burr closely compacted and binding in the periphery of a part without any loose ends and is within the dimensional l
24、imits of the part. Refer to AS1814 for titanium microstructure terms and definitions. 2.3 Unit Symbols Baume hydrometer scale unit for measuring specific gravity of liquids F degree Fahrenheit % percent (1% = 1/100) lbf pound-force ksi kips (1000 pounds) per square inch sp gr specific gravity SAE IN
25、TERNATIONAL AS7460C Page 4 of 19 3. TECHNICAL REQUIREMENTS 3.1 Material Shall be AMS4967 titanium alloy. 3.2 Design Finished (completely manufactured) parts shall conform to the following requirements: 3.2.1 Dimensions The dimensions of finished parts, after all processing, shall conform to the part
26、 drawing. Dimensions apply before any required coating with dry film lubricants. 3.2.2 Surface Texture Surface texture of finished parts, prior to any required coating, shall conform to the requirements as specified on the part drawing, determined in accordance with ASME B46.1. 3.2.3 Threads Screw t
27、hread UNJ profile and dimensions shall be in accordance with AS8879, unless otherwise specified on the part drawing. 3.2.3.1 Incomplete Threads Incomplete threads are permissible at the chamfered end and the juncture of the unthreaded portion of the shank or adjacent to the head as specified in AS30
28、62. 3.2.3.2 Chamfer The entering end of the thread shall be chamfered as specified on the part drawing. 3.2.4 Geometric Tolerances Part features shall be within the geometric tolerances specified on the part drawing and, where applicable, controlled in accordance with AS3063. 3.3 Fabrication 3.3.1 B
29、lanks Heads shall be formed by hot forming or machining. 3.3.1.1 Cleaning Blanks shall be cleaned prior to heat treatment in accordance with ASTM B600, or other methods approved by the purchaser. Blank surfaces shall be free of halogen compounds, such as residue from halogenated solvents and coolant
30、s, and salt from sweaty hands. Surfaces of parts, fixtures, racks, etc., shall be clean and free of dirt, water, oil, grease, paint, ink, crayon markings, dye pickup, finger prints, and other foreign material. After cleaning and prior to heat treatment, personnel handling blanks shall wear clean whi
31、te cotton gloves or equivalent. SAE INTERNATIONAL AS7460C Page 5 of 19 3.3.2 Heat Treatment Headed and machined blanks after cleaning as in 3.3.1.1 shall, before finishing the shank and the bearing surface of the head, cold working the head-to-shank fillet radius, and rolling the threads, be heat tr
32、eated as follows: 3.3.2.1 Heating Equipment Furnaces may be any type ensuring uniform temperature throughout the blanks being heated and shall be equipped with, and operated by, automatic temperature controllers and data recorders conforming to AMS2750. The heating medium or atmosphere shall cause n
33、either surface hardening nor embrittlement unless blanks are machined after heat treatment, to remove surface hardening. 3.3.2.2 Solution Heat Treatment Blanks shall be uniformly heated to a temperature within the range 1650 to 1740 F, held at the selected temperature within 25 F for 30 to 60 minute
34、s, and quenched in water. 3.3.2.3 Precipitation Heat Treatment Solution heat treated blanks shall be heated to a temperature within the range 900 to 1100 F, held at the selected temperature within 10 F for 4 to 8 hours, and cooled in air. 3.3.3 Contamination Removal The solution and precipitation he
35、at treated blanks, before cold working the fillet radius when specified and rolling the threads, shall have the full body, head-to-shank fillet, and bearing surface of the head free from surface contamination and contamination penetration caused by prior heat treatment. The removal process shall pro
36、duce no intergranular attack or corrosion, or changes of structure of the blanks. The metal removed from the bearing surface of the head and the full body diameter of the shank shall be as little as practicable to obtain a clean, smooth surface, and in no case shall be so great as to produce more cu
37、tting of flow lines in the head-to-shank junction. 3.3.4 Cold Working of Fillet Radius After removal of contamination as in 3.3.3, the head-to-shank fillet radius of headed parts having the radius complete throughout the circumference of the part shall, when specified, be cold worked sufficiently to
38、 remove all visual evidence of grinding or tool marks. If there is no visual evidence of grinding or tool marks prior to cold working, the fillet shall still be cold worked. Distortion due to cold rolling shall conform to Figure 1, unless otherwise specified on the part drawing. It shall not raise m
39、etal more than 0.002 inch above the contour at “A“ or depress metal more than 0.002 inch below the contour at “B“ as shown in Figure 1; distorted areas shall not extend beyond “C“ as shown in Figure 2. In configurations having an undercut associated with the fillet radius, the cold working will be r
40、equired only for 90 of fillet arc, starting at the point of tangency of the fillet radius and the bearing surface of the head. For shouldered bolts, having an unthreaded shank diameter larger than the thread major diameter and having an undercut associated with a fillet between the threaded shank an
41、d the shoulder of the unthreaded shank, the cold rolling will be required only for 90 of fillet arc, starting at the point of tangency of the fillet radius and the shouldered surface of the unthreaded shank. For parts with compound fillet radii between head and shank, cold work only the radius that
42、blends with the head. The shank diameter on close tolerance full shank bolts shall not exceed its maximum diameter limit after cold rolling the head-to-hank fillet radius. 3.3.5 Thread Rolling Threads shall be formed on the heat treated and finished blanks by a single rolling process after removal o
43、f contamination as in 3.3.3. 3.4 Product Marking Each part shall be identification marked as specified on the part drawing. The markings may be formed by forging or stamping, raised or depressed 0.010 inch maximum, with rounded root form on depressed characters. SAE INTERNATIONAL AS7460C Page 6 of 1
44、9 3.5 Mechanical Properties Parts shall conform to the requirements of 3.5.1. Threaded members of gripping fixtures for tensile tests shall be of sufficient size and strength to develop the full strength of the part without stripping the thread. The loaded portion of the shank shall have a minimum o
45、f three full thread turns from the thread runout exposed between the loading fixtures during the tensile test Finished parts shall be tested for ultimate tensile strength per MIL-STD-1312-8 in accordance with NASM1312-8. 3.5.1 Ultimate Tensile Strength at Room Temperature 3.5.1.1 Finished Parts Part
46、s shall have an ultimate tensile load not lower than that specified in Table 2 and shall be tested to failure, first measuring and recording the maximum tensile load achieved. If the size or shape of the part is such that failure would occur outside the threaded section but the part can be tested sa
47、tisfactorily, such as parts having a shank diameter equal to or less than the thread root diameter or having an undercut, parts shall conform to only the ultimate tensile strength requirements of 3.5.1.2; for such parts, the diameter of the area on which stress is based shall be the actual measured
48、minimum diameter of the part. Tension fasteners with either standard double hexagon drive or hexagon-type heads having a minimum metal condition in the head equal to the design parameters specified in AS1132 shall not fracture in the head-to-shank fillet radius except when this radius is associated
49、with an undercut or with a shank diameter less than the minimum pitch diameter of the thread. 3.5.1.2 Machined Test Specimens If the size or shape of the part is such that a tensile test cannot be made on the part, tensile tests shall be conducted in accordance with ASTM E8/E8M on specimens prepared as in 4.5.6. Tests on such specimens shall be conducted at a strain rate of 0.003 to 0.007 inch/inch/minute through the 0.2% off
