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 2015 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/AS7471GAEROSPACESTANDARDAS7471 REV. G Issued 1991-01 Reaffirmed 1997-07 Revised 2015
5、-03 Superseding AS7471FBolts and Screws, Nickel Alloy, UNS N07001 Tensile Strength 165 ksi, Corrosion and Heat Resistant Procurement Specification FSC 5306 RATIONALERevise requirements for oxide removal after all heat treatments. 1. SCOPE 1.1 Type This procurement specification covers bolts and scre
6、ws made from a corrosion and heat resistant, age hardenable nickel base alloy of the type identified under the Unified Numbering System as UNS N07001. The following specification designations and their properties are covered: AS7471 165 ksi minimum ultimate tensile strength at room temperature. 75 k
7、si stress-rupture strength at 1350 F. AS7471-1 165 ksi minimum ultimate tensile strength at room temperature. 99 ksi minimum ultimate shear strength at room temperature. 1.2 Application Primarily for aerospace propulsion systems applications where a good combination of tensile strength, and resistan
8、ce to relaxation at elevated temperatures up to approximately 1500 F is required. 1.3 Safety - Hazardous Materials While the materials, methods, applications, and processes described or referenced in this specification may involve the use of hazardous materials, this specification does not address t
9、he 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 safety of all personnel involved. SAE INTERNATIONAL AS7471G Page
10、 2 of 23 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 documents shall be the issue in effect on the date of the purchase order. In the eve
11、nt of conflict between the text of this specification 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 obtained. 2.1.1 SAE Publications Available from SAE Intern
12、ational, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org.2.1.1.1 Aerospace Material Specifications AMS2750 Pyrometry AMS5708 Nickel Alloy, Corrosion and Heat-Resistant, Bars, Wire Forgings, and Rings 58Ni - 19.5C
13、r - 13.5Co - 4.3Mo - 3.0Ti - 1.4Al Consumable Electrode or Vacuum Induction Melted 1975 F (1079 C) Solution Heat Treated 2.1.1.2 Aerospace Standards AS1132 Bolts, Screws and Nuts - External Wrenching UNJ Thread, Inch - Design Standard AS3062 Bolts, Screws and Studs, Screw Thread Requirements AS3063
14、Bolts, Screws and Studs, Geometric Control Requirements AS8879 Screw Threads - UNJ Profile, Inch Controlled Radius Root with Increased Minor Diameter 2.1.2 AIA/NAS Publications Available from Aerospace Industries Association, 1000 Wilson Boulevard, Suite 1700, Arlington, VA 22209-3928, Tel: 703-358-
15、1000, www.aia-aerospace.org.NASM1312-6 Fastener Test Methods, Method 6, Hardness NASM1312-8 Fastener Test Methods, Method 8, Tensile Strength NASM1312-10 Fastener Test Methods, Method 10, Stress-Rupture NASM1312-13 Fastener Test Methods, Method 13, Double Shear Test SAE INTERNATIONAL AS7471G Page 3
16、of 23 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 D3951 Commercial Packaging ASTM E8/E8M Standard Test Methods for Tension Testing of Metallic Materials ASTM E112 Determining A
17、verage Grain Size ASTM E139 Conducting Creep, Creep-Rupture, and Stress-Rupture Tests of Metallic Materials ASTM E140 Standard Hardness Conversion Tables for Metals ASTM E340 Standard Test Methods for Microetching Metals and Alloys ASTM E407 Standard Practice for Microetching Metals and Alloys ASTM
18、E930 Standard Test Methods for Estimating the Largest Grains Observed in a Metallographic Section (ALA Grain Size) ASTM E1417/E1417M Standard Practice for Liquid Penetrant Testing 2.1.4 ASME Publications Available from ASME, P.O. Box 2900, 22 Law Drive, Fairfield, NJ 07007-2900, Tel: 800-843-2763 (U
19、.S./Canada), 001-800-843-2763 (Mexico), 973-882-1170 (outside North America), www.asme.org.ASME B46.1 Surface Texture (Surface Roughness, Waviness, and Lay) 2.2 Definitions BURR: A rough edge or ridge left on the metal due to cutting, grinding, piercing, or blanking operation. COLD ROLLING: Forming
20、material 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 or the product with specified requirements. DEFECTIVE: A unit of the product whic
21、h contains one 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 the shank caused by plastic
22、 forming of the head. INCLUSION: Nonmetallic particles originating from the material making process. They may exist as discrete particles or strings of particles extending longitudinally. SAE INTERNATIONAL AS7471G Page 4 of 23 LAP: Surface imperfection caused by folding over metal fins or sharp corn
23、ers 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 width with a depth of 0.0005 inch when viewed at 200X ma
24、gnification. 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
25、 single heat 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 im
26、purity in the metal bar, often the result of an inclusion that has been extended during the rolling process. TIGHT BURR: A burr closely compacted and binding in the periphery of a part without loose ends and is within the dimensional limits of the part. 2.3 Unit Symbols C - degree Celsius F - degree
27、 Fahrenheit cm3 - cubic centimeter g - gram (mass) HRC - hardness Rockwell C scale lbf - pound-force % - percent (1% = 1/100) sp gr - specific gravity ksi - kips (1000 pounds) per square inch 3. TECHNICAL REQUIREMENTS 3.1 Material Shall be AMS5708 alloy heading stock. 3.2 Design Finished (completely
28、 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 part drawing. Dimensions apply after plating but before coating with solid film lubricants. SAE INTERNATIONAL AS7471G Pag
29、e 5 of 23 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 ASME B46.1. 3.2.3 Threads Screw thread UNJ profile and dimensions shall be in accordance with AS8879, unle
30、ss 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 or adjacent to the head as specified in AS3062. 3.2.3.2 Chamfer The entering end of the thread shall be
31、 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 Blanks Heads shall be formed by forging; machined heads are
32、not permitted, except lightening holes may be produced by any suitable method. Wrenching recesses may be forged or machined. Flash or chip clearance in machined recesses shall not cause recess dimensions to exceed the specified limits. 3.3.2 Heat Treatment Before finishing the shank and the bearing
33、surface of the head, cold rolling the head-to-shank fillet radius, and rolling the threads, headed blanks shall be solution and stabilization heat treated as follows; precipitation heat treatment shall follow cold rolling of the fillet radius and rolling the threads. 3.3.2.1 Heating Equipment Furnac
34、es may be any type ensuring uniform temperature throughout the parts 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 no surface hardening by carburizing or nitriding. 3.
35、3.2.2 Solution Heat Treatment Headed blanks shall be solution heat treated by heating to a temperature within the range 1900 to 1975 F, holding at the selected temperature within 25 F for 1 to 4 hours, and cooling at a rate equivalent to air cool or faster. 3.3.2.2.1 A temperature lower than 1900 F
36、may be used provided the furnace control is such that during the holding period no part is below 1875 F. 3.3.2.3 Stabilization Heat Treatment Solution heated blanks shall be stabilization heat treated by heating to 1550 F 15 F, holding at heat for 4 hours 0.5 hour, and cooling in air. SAE INTERNATIO
37、NAL AS7471G Page 6 of 23 3.3.2.4 Precipitation Heat Treatment After cold rolling the fillet radius as in 3.3.4 and rolling the threads as in 3.3.5, parts shall be precipitation heat treated by heating to 1400 F 15 F in a controlled atmosphere, holding at heat for 16 hours 1 hour, and cooling at a ra
38、te equivalent to air cool. 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 stabilization heat treated blanks prior to cold rolling the underhead fillet radius
39、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 with a metallic shee
40、n able to reflect light. 3.3.4 Cold Rolling of Fillet Radius After removal of oxide 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 be cold rolled. The cold rolling shall be sufficient to remove all visual evidenc
41、e of grinding or tool marks. Distortion due to cold 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
42、 areas shall not extend beyond “C” as shown in Figure 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 the point of tangency of the fillet radius and the bearing surface of the head. For shoulde
43、red parts, having an unthreaded shank diameter larger 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 tange
44、ncy of the fillet radius and the shouldered surface of the unthreaded shank. The shank diameter on close tolerance full shank parts shall not exceed its maximum diameter limit after cold rolling the head-to-shank fillet radius. 3.3.5 Thread Rolling Threads shall be formed on the finished blanks by a
45、 single rolling process after removal of oxide as in 3.3.3. 3.3.6 Cleaning Parts, after finishing, shall be degreased and immersed in one of the 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 roo
46、m 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 nitric 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, t
47、he parts shall be thoroughly rinsed in clean water at 70 to 200 F. 3.4 Product Marking Each part shall be identification marked as specified by the part drawing. The markings may be formed by forging or stamping, raised or depressed no more than 0.010 inch maximum, with rounded root form on depresse
48、d characters. SAE INTERNATIONAL AS7471G Page 7 of 23 3.5 Plating or Coating Where required, surfaces shall be plated or coated as specified by the part drawing. When coating with a solid film lubricant is required, the underhead bearing surface, unthreaded shank and threads shall be coated as specif
49、ied on the part drawing; other surfaces are optional to coat, unless otherwise specified. Plating thickness shall be determined in accordance with the plating specification. 3.6 Mechanical Properties Where AS7471 is specified, parts shall conform to the requirements of 3.6.1, 3.6.2, 3.6.3. Where AS7471-1 is specified, parts shall conform to the requirements of 3.6.1, 3.6.2, and 3.6.4. Threaded members of gripping fixt
