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 2015 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:/www.sae.org/technical/standards/AS7475D AEROSPACE STANDARD AS7475 REV. D Issued 1991-01 Revised 2010-08Reaffirmed
5、 2015-04 Superseding AS7475C Bolts, Cobalt-Chromium-Nickel Alloy, UNS R30159, Tensile Strength 260 ksi, Procurement Specification FSC 5306 RATIONALE AS7475D has been reaffirmed to comply with the SAE five-year review policy. 1. SCOPE This procurement specification covers bolts made from a corrosion
6、resistant, work-strengthened, cobalt-chromium-nickel alloy of the type identified under the Unified Numbering System as UNS R30159. 1.1 Type The following specification designations and their properties are covered: AS7475 260 ksi minimum ultimate tensile strength at room temperature 205 ksi minimum
7、 ultimate tensile strength at 1100 F 140 ksi stress-rupture strength at 1100 F 135 ksi tension to 13.5 ksi tension fatigue at room temperature AS7475-1 260 ksi minimum ultimate tensile strength at room temperature 132 ksi minimum ultimate shear strength at room temperature 1.1.1 Classification 260 k
8、si minimum tensile strength at room temperature. 1.2 Application Primarily for use in aerospace propulsion system applications where an excellent combination of strength, creep, fatigue, and relaxation resistance is required. 1.3 Safety - Hazardous Materials While the materials, methods, application
9、s, 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 hazardous
10、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. The appli
11、cable 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 laws and regu
12、lations unless a specific exemption has been 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. AMS2750 Pyrometry AMS5842 Cobalt-Nickel Alloy, Corr
13、osion Heat Resistant, Bars, 19Cr - 36Co - 25Ni - 7.0Mo - 0.50Cb (Nb) - 2.9Ti - 0.20Al - 9.0Fe, Vacuum Induction Plus Vacuum Consumable Electrode Melted Solution Heat Treated and Work Strengthened AS3062 Bolts, Screws and Studs, Screw Thread Requirements AS3063 Bolts, Screws and Studs, Geometric Cont
14、rol Requirements AS3658 Bolt, Machine - Double Hexagon Extended Washer Head, Close Tolerance Shank, Cobalt-Nickel Alloy, UNS R30159, 260KSI Min AS3659 Bolt, Machine - Double Hexagon Extended Washer Head, Drilled, Close Tolerance Shank, Cobalt-Nickel Alloy, UNS R30159, 260KSI Min AS8879 Screw Threads
15、 - UNJ Profile, Inch, Controlled Radius Root with Increased Minor Diameter 2.1.2 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 E 8 Tension Testing of Metallic Materials ASTM E 21 Elev
16、ated Temperature Tension Tests of Metallic Materials ASTM E 112 Determining Average Grain Size ASTM E 139 Conducting Creep, Creep-Rupture, and Stress-Rupture Tests in Metallic Materials ASTM E 140 Standard Hardness Conversion Tables for Metals ASTM E 1417 Liquid Penetrant Examination ASTM D 3951 Com
17、mercial Packaging SAE INTERNATIONAL AS7475D 2 OF 222.1.3 AIA/NAS Publications Available from Aerospace Industries Association, 1000 Wilson Boulevard, Suite 1700, Arlington, VA 22209-3928, Tel: 703-358-1000, www.aia-aerospace.org. NASM 1312-6 Fastener Test Methods, Method 6, Hardness NASM 1312-8 Fast
18、ener Test Methods, Method 8, Tensile Strength NASM 1312-10 Fastener Test Methods, Method 10, Stress-Rupture NASM 1312-11 Fastener Test Methods, Method 11, Tension Fatigue NASM 1312-13 Fastener Test Methods, Method 13, Double Shear Test NASM 1312-18 Fastener Test Methods, Method 18, Elevated Temperat
19、ure Tensile Strength NASM 21296 Bolt, Tension, Steel, 260 ksi Ftu, 450 F, External Wrenching, Spline Drive, Flanged Head 2.1.4 ASME Publications Available from American Society of Mechanical Engineers, 22 Law Drive, P.O. Box 2900, Fairfield, NJ 07007-2900, Tel: 973-882-1170, www.asme.org. ASME B46.1
20、 Surface Texture (Surface Roughness, Waviness, and Lay) 2.2 Definitions BURR: A rough edge or ridge left on the metal due to a cutting, grinding, piercing or blanking operation. COLD WORKING: Forming material below the recrystallation temperature. CRACK: Rupture in the material which may extend in a
21、ny direction and which may be intercrystalline or transcrystalline in character. 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: The discernible difference in the etched appe
22、arance between the head and shank caused by the plastic 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. INSPECTION LOT: Shall consist of parts from a single prod
23、uction lot, of the same part number. LAP: Surface imperfection 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 havin
24、g its length equal to or greater than three times its width 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
25、dull cutting tools. NON-CONFORMANCE: A departure from a specified requirement for any characteristic. NON-CONFORMING UNIT: A unit of the product that has one or more non-conformances. SAE INTERNATIONAL AS7475D 3 OF 22PRODUCTION INSPECTION LOT: Shall be all finished parts of the same part number, mad
26、e 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 the vendors inspection at the same time. ROOM TEMPERATURE: Ambient temperature (68 F approximately). SEAM: Longitudinal surface imperfection in the form of
27、an unwelded, open fold in the material. STRINGER: A solid nonmetallic impurity in the metal or 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
28、dimensional limits of the part. 2.3 Unit Symbols F degree Fahrenheit % percent (1% = 1/100) lbf pounds force ksi kips (1000 pounds) per square inch sp gr specific gravity HRC hardness, Rockwell C scale 3. TECHNICAL REQUIREMENTS 3.1 Material Shall be AMS5842 alloy heading stock. 3.2 Design Finished (
29、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 part drawing. Dimensions apply after plating but before coating with solid film lubricants. 3.2.2 Surface Textu
30、re 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, unless otherwise specified on the
31、 part drawing. 3.2.3.1 Incomplete Lead and Runout Threads Incomplete threads are permissible at the entering end and at the juncture of the unthreaded portion of the shank or adjacent to the head as specified in AS3062. SAE INTERNATIONAL AS7475D 4 OF 223.2.3.2 Chamfer The entering end of the thread
32、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, in accordance with AS3063. 3.3 Fabrication 3.3.1 Blanks Heads shall be formed by hot or cold forging; machined h
33、eads are 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 bea
34、ring surface of the head, cold working the head-to-shank fillet radius, and rolling the threads, headed blanks shall be aged as follows: 3.3.2.1 Heating Equipment Furnaces may be any type ensuring uniform temperature throughout the parts being heated and shall be equipped with, and operated by, auto
35、matic temperature controllers and data recorders conforming to AMS 2750. The heating medium or atmosphere shall cause no surface hardening by carburizing or nitriding. 3.3.2.2 Aging Heat Treatment Headed blanks shall be aged by heating to a temperature within the range 1200 to 1250 F, holding at the
36、 selected temperature within 25 F for 4 to 4.5 hours, and cooling at a rate equivalent to air cooling. 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 heat treated
37、, work-strengthened, and aged blanks prior to cold working the fillet radius 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
38、 little as practicable to obtain a clean, smooth surface. 3.3.4 Cold Working 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 worked sufficiently to remove all visual
39、 evidence of grinding or tool marks. Distortion due to cold working 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; d
40、istorted areas shall not extend beyond “C” shown in Figure 2. In configurations having an undercut connected with the fillet radius, the cold working will be required 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
41、 bolts, 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 working will be required only for 90 of the fillet arc, starting at the point of tangency of
42、the fillet radius and the shouldered surface of the unthreaded shank. The shank diameter on close tolerance full shank bolts shall not exceed its maximum diameter limit after cold working the head-to-shank fillet radius. 3.3.5 Thread Rolling Thread shall be formed on the finished blanks by a single
43、cold rolling process after removal of oxide as in 3.3.3. SAE INTERNATIONAL AS7475D 5 OF 223.3.6 Cleaning Parts, after finishing, shall be degreased and imersed 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 n
44、ot 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 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
45、 from the cleaning solution, 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 on the part drawing. The markings may be formed by forging or stamping, raised or depressed 0.010 inch maximum, with rounded root for
46、m 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 film lubricants is required, the under head bearing surface, the unthreaded shank, and the threads shall be coated as specified on the part
47、drawing; other surfaces are optional to coat, unless otherwise specified. Plating thickness shall be determined in accordance with the requirements in the applicable plating specification. 3.6 Mechanical Properties Where AS7475 is specified, parts shall conform to the requirements of 3.6.1, 3.6.2, 3
48、.6.3, 3.6.4, and 3.6.5. Where AS7475-1 is specified, parts shall conform to the requirements of 3.6.1, 3.6.3, and 3.6.6. Threaded members of gripping fixtures for tensile tests, and fatigue tests shall be of sufficient size and strength to develop the full strength of the part without stripping the
49、thread. The loaded portion of the shank shall have two to three full threads from the thread runout exposed between the loading fixtures during tensile test. AS7475 finished parts shall be tested in accordance with the following test methods: a. Hardness: MIL-STD-1312-6 in accordance with NASM 1312-6 b. Ultimate Tensile Strength at Room Temperature: MIL-STD-1312-8 in accordance with NASM 1312-8 c. Ultimate Tensile Strength at 11
