SAE AS 7478B-1997 Bolts and Screws Steel UNS S66286 Classification 130 ksi 1200 Degrees F 1800 Degrees F Solution Heat Treated Aged After Roll Threaded Procurement Specification fo.pdf

1、AEROSPACE STANDARDAS7478REV.BIssued 1991-01Revised 1997-12Reaffirmed 2006-05Superseding AS7478ABolts and Screws, Steel, UNS S66286Classification: 130 ksi/1200 F1800 F Solution Heat Treated, Aged After Roll ThreadedProcurement Specification forFSC 53061. SCOPE:This procurement specification covers bo

2、lts and screws made from a corrosion and heat resistant, age hardenable iron base alloy of the type identified under the Unified Numbering System as UNS S66286.1.1 Type:The following specification designations and their properties are covered:AS7478: 130 ksi minimum ultimate tensile strength at room

3、 temperature65 ksi stress-rupture strength at 1200 FAS7478-2: 130 ksi minimum ultimate tensile strength at room temperature78 ksi minimum ultimate shear strength at room temperature1.1.1 Classification: 130 ksi minimum tensile strength at room temperature1200 F maximum test temperature of parts1.2 A

4、pplication:Primarily for aerospace propulsion system applications where stress-rupture strength and creep resistance are required at elevated temperature.1.3 Safety - Hazardous Materials:While the materials, applications, and processes described or referenced in this specification may involve the us

5、e 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 materials and to take necessary precautionary measures to ensure the health and s

6、afety of all personnel involved.RATIONALE This document has been reaffirmed to comply with the SAE 5-year Review policy. 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 v

7、oluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefrom, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites you

8、r written comments and suggestions. Copyright 2006 SAE International All rights reserved. No part of this publication 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

9、permission of SAE. TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada) Tel: 724-776-4970 (outside USA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction o

10、r networking permitted without license from IHS-,-,-SAE AS7478 Revision B- 2 -2. REFERENCES:2.1 Applicable Documents:The following publications form a part of this specification to the extent specified herein. The latest issue of SAE publications shall apply. The applicable issue of other documents

11、shall be the issue in effect on the date of the purchase order.2.1.1 SAE Publications: Available from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001.AMS 2759/3 Heat Treatment of Precipitation Hardening, Corrosion Resistant and Maraging Steel PartsAMS 5731 Steel Bars, Forgings, Tubing, and Ri

12、ngs, Corrosion and Heat Resistant, 15Cr-25.5Ni-1.2Mo-2.1Ti-0.006B-0.30V Consumable Electrode Melted, 1800 F (982 C), Solution Heat TreatedAS1132 Design Parameters for Bolts and Screws, External Wrenching, Unified Thread Inch SeriesAS3062 Bolts, Screws, and Studs, Screw Thread RequirementsAS3063 Bolt

13、s, Screws, and Studs, Geometric Control Requirements2.1.2 U.S. Government Publications: Available from DODSSP, Subscription Services Desk, Building 4D, 700 Robbins Avenue, Philadelphia, PA 19111-5094.MIL-S-8879 Screw Threads, Controlled Radius Root With Increased Minor Diameter; General Specificatio

14、ns ForMIL-STD-1312-6 Fastener Test Methods, Method 6, HardnessMIL-STD-1312-8 Fastener Test Methods, Method 8, Tensile StrengthMIL-STD-1312-10 Fastener Test Methods, Method 10, Stress-RuptureMIL-STD-1312-13 Fastener Test Methods, Method 13, Double Shear Test2.1.3 ASTM Publications: Available from AST

15、M, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959.ASTM E 8 Tension Testing of Metallic MaterialsASTM E 112 Determining Average Grain SizeASTM E 139 Conducting Creep, Creep-Rupture, and Stress-Rupture Test of Metallic MaterialsASTM E 140 Standard Hardness Tables for MetalsASTM E 1417 Liquid

16、Penetrant ExaminationASTM D 3951 Commercial PackagingCopyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AS7478 Revision B- 3 -2.1.4 ASME Publications: Available from ASME, 22 Law Drive, P.O. Box 290

17、0, Fairfield, NJ 07007-2900.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 a cutting, grinding, piercing or blanking operation.COLD ROLLING: Forming material below the recrystallation temperature.CRACK: Rupture in

18、 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 one or more defects.DISCONTINUITY: An interruption in the norma

19、l physical structure or configuration of a part; such as a lap, seam, inclusion, crack, machining tear, or stringer.HEAT PATTERN: The discernible difference in etched appearance between the head and shank caused by the plastic forming of the head.INCLUSION: Nonmetallic particles originating from the

20、 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 surface. The allowable lap depth shall not exceed the limit specified

21、 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.MACHINING TEAR: A pattern of short, jagged individual cracks, generally at right angles to the directio

22、n 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 of alloy, heat treated at the same time to the same specified condition, produced as one continuous run

23、, 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 the metal bar, often the result of inclusions that have been extended during the rolling process.Copyright S

24、AE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AS7478 Revision B- 4 -2.2 (Continued):TIGHT BURR: A burr closely compacted and binding in the periphery of a part without any loose ends and is within the dim

25、ensional limits of the part.2.3 Unit Symbols: - degree, angleC - degree CelsiusF - degree Fahrenheit% - percent (1% = 1/100)lbf - pound-forceksi - kips (1000 pounds) per square inchsp gr - specific gravityHRC - hardness, Rockwell C scale3. TECHNICAL REQUIREMENTS:3.1 Material:Shall be AMS 5731 steel

26、heading stock, unless otherwise specified on 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 specified on the

27、part drawing. Dimensions apply after plating but before coating with 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 ASME B46.1.3.2.3 Threads:

28、Screw thread UNJ profile and dimensions shall be in accordance with MIL-S-8879, 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 or adjacent to the

29、 head as specified in 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 accordance with AS306

30、3.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AS7478 Revision B- 5 -3.3 Fabrication:3.3.1 Blanks: Heads shall be formed by hot forging, cold forging; or machining. Heading stock to be hot for

31、ged shall be heated to a temperature not higher than 2100 F. 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 dimensions to exceed the specified limits.3.3.2 Heat Treatment: Shall confo

32、rm to the technical requirements and other provisions specified in AMS 2759/3 for A-286, 1800 F solution heat treatment and 1325 F aging treatment.3.3.2.1 Solution Heat Treatment: Headed and machined blanks of AMS 5731, unless machined from solution heat treated stock, shall, before finishing the sh

33、ank and the bearing surface of the head, cold rolling the head-to-shank fillet radius when specified, and rolling the threads, be solution heat treated as in 3.3.2. Blanks of other materials shall be solution heat treated in accordance with the applicable material specification. If blanks are machin

34、ed from solution heat treated stock, only the aging treatment as in 3.3.2.2 is necessary.3.3.2.2 Aging Treatment: After cold rolling the fillet radius as in 3.3.4 when specified and rolling the threads as in 3.3.5, parts of AMS 5731 shall be heat treated by aging as in 3.3.2. Parts of other material

35、s shall be heat treated by aging after cold rolling the fillet radius as in 3.3.4 when specified and rolling the threads as in 3.3.5, in accordance with the applicable material specification.3.3.3 Oxide Removal: Surface oxide and oxide penetration resulting from prior heat treatment shall be removed

36、 from the full body diameter and bearing surface of the head of the solution heat treated blanks prior to cold rolling the fillet radius when specified and rolling the threads. The oxide removal process shall produce no intergranular attack or corrosion of the blanks. The metal removed from the bear

37、ing 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 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 circu

38、mference of the part when specified shall be cold rolled sufficiently to remove all visual evidence of grinding or tool marks. Distortion due to cold rolling shall conform to Figure 1, unless otherwise specified on the part drawing. It shall not raise metal more than 0.002 inch above the contour at

39、“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 1. In configurations having an undercut connected with the fillet radius, the cold rolling will be required only for 90 of fillet arc, starting at t

40、he 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 connected with a fillet between the threaded shank and the shoulder of the unthreaded shank, the cold w

41、orking 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.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IH

42、S-,-,-SAE AS7478 Revision B- 6 -3.3.5 Thread Rolling: Threads shall be formed on the finished blanks by a single cold 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 temperat

43、ure 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 nitric acid (sp gr 1.42) and 4 volumes of water for 1

44、0 to 15 minutes at140 to 160 F.3.3.6.1 Immediately after removal 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 by the part drawing. The markings may be formed by forging or stamping

45、, raised or depressed 0.010 inch max, with rounded root form on depressed characters.3.5 Plating or Coating:Where required, surfaces shall be plated as specified by the part drawing. Where coating with dry film lubricants is required, the under-head bearing surface, unthreaded shank, and threads sha

46、ll 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.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitte

47、d without license from IHS-,-,-SAE AS7478 Revision B- 7 -3.6 Mechanical Properties:Where AS7478 is specified, parts shall conform to the requirements of 3.6.1, 3.6.2, and 3.6.4. Where AS7478-2 is specified, parts shall conform to the requirements of 3.6.1, 3.6.2, and 3.6.3. Threaded members of gripp

48、ing 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.AS7478 finished parts shall be tested in accordance with the following test methods:a. Hardness: MIL-STD-1312-6b. Room Temperature Ultimate

49、 Tensile Strength: MIL-STD-1312-8c. Stress-Rupture Strength at 1200 F: MIL-STD-1312-10AS7478-2 finished parts shall be tested in accordance with the following test methods:a. Hardness: MIL-STD-1312-6b. Room Temperature Ultimate Tensile Strength: MIL-STD-1312-8c. Ultimate Double Shear at Room Temperature: MIL-STD-1312-133.6.1 Ultimate Tensile Strength at Room Temperature:3.6.1.1 Finished