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 2013 SAE International All rights reserved. No part of this pub
3、lication 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
4、(outside USA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/AS7479DAEROSPACESTANDARDAS7479 REV. DIssued 1991-01 Reaffirmed 2012-11 Revised 2013-
5、09 Superseding AS7479C Bolts and Screws, Steel, UNS S66286 1650 F Solution Heat Treated Precipitation Heat Treated Before Roll Threaded FSC 5306 RATIONALETABLE 4 - Sampling Data Major A Sample Size for lot size 10 001 to 35 000 changed from 169 to 189.1. SCOPE 1.1 Type This specification covers bolt
6、s and screws made from a corrosion and heat resistant, precipitation hardenable iron base alloy of the type identified under the Unified Numbering System as UNS S66286, and of 130 000 psi tensile strength at room temperature, with maximum test temperature of parts at 1200 F. 1.2 Application Primaril
7、y for aerospace propulsion system applications where a good combination of strength and resistance to relaxation at elevated temperatures is required. 1.3 Safety - Hazardous Materials While the materials, applications, and processes described or referenced in this specification may involve the use o
8、f 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 hazardous materials and to take necessary precautionary measures to ensure the health and safe
9、ty of all personnel involved. SAE INTERNATIONAL AS7479D Page 2 of 22 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. The applicable issue of other publications shall be th
10、e 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 been
11、obtained. 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 724-776-4970 (outside USA), www.sae.org.AMS2759/3 Heat Treatment Precipitation-Hardening, Corrosion-Resistant and Maraging Steel Parts AM
12、S5734 Steel, Corrosion and Heat-Resistant, Bars, Wire, Forgings, and Tubing, 15Cr - 25.5Ni - 1.2Mo - 2.1Ti - 0.006B - 0.30V, Consumable Electrode Melted, 1650 F (899 C) Solution Heat Treated AS1132 Bolts, Screws and Nuts - External Wrenching, UNJ Thread, Inch - Design Standard AS3062 Bolts, Screws a
13、nd Studs, Screw Thread Requirements AS3063 Bolts, Screws, and Studs, Geometric Control Requirements AS8879 Screw Threads - UNJ Profile, Inch Controlled Radius Root with Increased Minor Diameter 2.1.2 NAS Publications Available from Aerospace Industries Association, 1000 Wilson Boulevard, Suite 1700,
14、 Arlington, VA 22209-3928, Tel: 703-358-1000, www.aia-aerospace.org.NASM 1312-6 Fastener Test Methods, Method 6, Hardness NASM 1312-8 Fastener Test Methods, Method 8, Tensile Strength NASM 1312-10 Fastener Test Methods, Method 10, Stress-Rupture 2.1.3 ASME Publications Available from American Societ
15、y of Mechanical Engineers, 22 Law Drive, P.O. Box 2900, Fairfield, NJ 07007-2900, Tel: 973-882-1170, www.asme.org.ASME B46.1 Surface Texture (Surface Roughness, Waviness, and Lay) SAE INTERNATIONAL AS7479D Page 3 of 22 2.1.4 ASTM Publications Available from ASTM International, 100 Barr Harbor Drive,
16、 P.O. Box C700, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, www.astm.org.ASTM E8 Tension Testing of Metallic Materials ASTM E140 Standard Testing of Metallic Materials ASTM E1417 Liquid Penetrant Examination ASTM D3951 Commercial Packaging 2.2 Unit Symbols C - degree Celsius F - degree Fahr
17、enheit % - percent (1% = 1/100) lbf - pounds force ksi - kips (1000 pounds) per square inch sp gr - specific gravity HRC - hardness, Rockwell C scale 2.3 Definitions BURR: A rough edge or ridge left on the metal due to a cutting, grinding, piercing or blanking operation. COLD ROLLING: Forming materi
18、al below the recrystallation temperature. CRACK: Rupture in the material 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 on
19、e or more defects. DISCONTINUITY: An interruption in the normal physical structure or configuration of a part; such as a lap, seam, inclusion, crack, machining tear, or stringer. HEAT PATTERN: A discernible difference in etched appearance between the head and shank caused by the plastic forming of t
20、he head. INCLUSION: Nonmetallic particles originating from the material making process. They may exist as discrete particles or strings of particles extending longitudinally. LAP: Surface imperfection caused by folding over metal fins or sharp corners and then rolling or forging them into the surfac
21、e. 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 width with a depth of 0.0005 inch when viewed at 200X magnification. SAE INTERNATIONAL AS7479D Page 4 of 22
22、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 all finished parts of the same part number, made from a single heat
23、 of alloy, heat treated at the same time to the same specified condition, produced as one continuous run, and submitted for vendors inspection at the same time. SEAM: Longitudinal surface imperfection in the form of an unwelded, open fold in the material. STRINGER: A solid nonmetallic impurity in th
24、e 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 limits of the part. 3. TECHNICAL REQUIREMENTS 3.1 Material Shall be AMS5734
25、 steel heading stock, unless otherwise specified on the part drawing. 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 including plating, shall conform to the requirements as speci
26、fied on the part drawing. Dimensions shall apply after plating but before coating with solid dry film lubricants. 3.2.2 Surface Texture Surface texture of finished parts, prior to plating or coating, shall conform to the requirements as specified on the part drawing, determined in accordance with AS
27、ME B46.1. 3.2.3 Threads Screw thread UNJ profile and dimensions shall be in accordance with AS8879, unless otherwise specified on the part drawing.3.2.3.1 Incomplete Lead and Runout Threads Incomplete threads are permissible at the entering end and the juncture of the unthreaded portion of the shank
28、 or adjacent to the head in accordance with AS3062. 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
29、 accordance with AS3063. SAE INTERNATIONAL AS7479D Page 5 of 22 3.3 Fabrication 3.3.1 Blanks Heads shall be formed by hot-cold forging at a temperature not higher than 2100 F, by cold forging or machining. Lightening holes may be produced by any suitable method. Wrenching recesses may be forged or m
30、achined. Flash or chip clearance in machined recesses shall not cause recess dimensions to exceed the specified limits. 3.3.2 Heat Treatment Shall conform to the technical requirements and other provisions specified in AMS2759/3 for A286, 1650 F solution treatment and aging treatment. 3.3.2.1 Soluti
31、on Heat Treatment Headed blanks of AMS5734 shall, before finishing the shank and the bearing surface of the head, cold rolling the head-to-shank fillet radius, and rolling the threads, be solution heat treated as in 3.3.2.3.3.2.2 Aging Treatment After solution heat treatment as in 3.3.2.1, blanks sh
32、all be heat treated by aging as in 3.3.2.3.3.3 Oxide Removal Surface oxide and oxide penetration resulting from prior heat treatment shall be removed from the full body diameter and bearing surface of the head of the solution and aged blanks prior to cold rolling the under head fillet radius when sp
33、ecified and rolling the threads. The oxide removal process shall produce no intergranular attack or corrosion 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. 3.3.4 Cold
34、Rolling of Fillet Radius After removal of oxide as in 3.3.3, the head-to-shank fillet radius of parts having the radius complete throughout the circumference of the part, when specified, shall be cold rolled sufficiently to remove all visual evidence of grinding or tool marks. Distortion due to cold
35、 rolling shall conform to Figure 2, unless otherwise specified on the part drawing. It shall not raise metal 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 2; distorted areas shall not extend beyond “C” as shown in Figu
36、re 2. In configurations having an undercut connected with the fillet radius, the cold rolling will be required only for 90 degrees of fillet arc, starting at thepoint of tangency of the fillet radius and the bearing surface of the head. For shouldered bolts, having an unthreaded shank diameter large
37、r than the thread major diameter and having an undercut connected with a fillet between the threaded shank and the shoulder of the unthreaded shank, the cold rolling will be required only for 90 degrees of fillet arc, starting at the point of tangency of the fillet radius and the shouldered surface
38、of the unthreaded shank. 3.3.5 Thread Rolling Threads shall be formed on the heat treated and finished blanks by a single cold rolling process after removal of oxide as in 3.3.3. SAE INTERNATIONAL AS7479D Page 6 of 22 3.3.6 Cleaning Parts, after finishing, shall be degreased and immersed in one of t
39、he following solutions for the time and temperature shown:a. One volume of nitric acid (sp gr 1.42) and 9 volumes of water for not less than 20 minutes at room temperature. b. One volume of nitric acid (sp gr 1.42) and 4 volumes of water for 30 to 40 minutes at room temperature. c. One volume of nit
40、ric acid (sp gr 1.42) and 4 volumes of water for 10 to 15 minutes at 140 to 160 F. 3.3.6.1 Water Rinse Immediately after removal from the cleaning solution, the parts shall be thoroughly rinsed in (70 to 200 F) water. 3.4 Product Marking Each part shall be identification marked as specified by the p
41、art drawing. The markings may be formed by forging or stamping, raised or depressed 0.010 inch maximum, with rounded root form on depressed characters. 3.5 Plating or Coating Where required, surfaces shall be plated or coated as specified by the part drawing. Where coating with solid dry film lubric
42、ants is required, the under-head bearing surface, unthreaded shank, and threads shall be coated as specified on the part drawing; other surfaces are optional to coat, unless otherwise specified. Plating thickness determined in accordance with plating specification. 3.6 Mechanical Properties Parts sh
43、all conform to the requirements of 3.6.1, 3.6.2 and 3.6.3. Threaded members of gripping fixtures for tensile and stress-rupture tests shall be of sufficient size and strength to develop the full strength of the part without stripping the thread. Finished parts shall be tested in accordance with the
44、following applicable test methods: a. Hardness: MIL-STD-1312-6 in accordance with NASM 1312-6 b. Room Temperature Ultimate Tensile Strength: MIL-STD-1312-8 in accordance with NASM 1312-8 c. Stress-Rupture Strength at 1200 F: MIL-STD-1312-10 in accordance with NASM 1312-10 3.6.1 Ultimate Tensile Stre
45、ngth at Room Temperature 3.6.1.1 Finished Parts Tension bolts, such as hexagon, double hexagon, and spline drive head, shall have an ultimate tensile load not lower than that specified in Table 2A and shall be tested to failure in order to observe fracture location, first measuring and recording the
46、 maximum tensile load achieved. Screws, such as 100 degree flush head, pan head, and fillister head, shall have an ultimate tensile load not lower than that specified in Table 2B; screws need not be tested to failure, however the maximum tensile load achieved shall be measured and recorded. If the s
47、ize or shape of the part is such that failure would occur outside the threaded section but the part can be tested satisfactorily, such as parts having a shank diameter equal to or less than the minimum pitch diameter or having an undercut, parts shall have an ultimate tensile strength not lower than
48、 130 ksi; for such parts, the diameter of the area on which stress is based shall be the actual measured minimum diameter of the part. Tension fasteners with either standard hexagon, double hexagon or spline drive type heads having a minimum metal condition in the head equal to the design parameters
49、 specified in AS1132 shall not fracture in the head-to-shank fillet radius except when this radius is connected with an undercut or with a shank diameter less than the minimum pitch diameter of the thread. SAE INTERNATIONAL AS7479D Page 7 of 22 3.6.1.2 Machine 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 on specimen
