1、AEROSPACE MATERIAL SPECIFICATIONAMS 2680CIssuedRevisedSuperseding AMS 2680BElectron-Beam WeldingFor Fatigue Critical Applications1. SCOPE:1.1 Purpose: This specification defines the procedures and requirements for joining metals and alloys using the electron beam welding process.1.2 Application: The
2、se procedures are used typically for high quality, electron-beam welding of aerospace components, the failure of which could cause loss of the aerospace vehicle or one of its major components, loss of control, or significant injury to occupants of a manned aerospace vehicle, but usage is not limited
3、 to such applications.1.2.1 The procedure covered by this specification is recommended for square groove and square scarf-butt joints for fatigue critical applications.: 2. APPLICABLE DOCUMENTS: The issue of the following documents in effect on the date of the purchase order forms a part of this spe
4、cification to the extent specified herein. The supplier may work to a subsequent revision of a document unless a specific document issue is specified. When the referenced document has been canceled and no superseding document has been specified, the last published issue of that document shall apply.
5、2.1 SAE Publications: Available from SAE, Inc., 400 Commonwealth Drive, Warrendale, PA 15096-0001.AMS 2630 Ultrasonic Inspection, Product Over 0.5 Inch (12.5 mm) ThickAMS 2631 Ultrasonic Inspection, Titanium and Titanium Alloy Bar and BilletAMS 2632 Ultrasonic Inspection of Thin Materials, 0.5 Inch
6、(13 mm) and ThinnerAMS-STD-1595 Qualification of Aircraft, Missile and Aerospace Fusion WeldersARP1333 Nondestructive Testing of Electron Beam Welded Joints in Titanium-Base AlloysReaffirmed 1981-042001-062010-03SAE Technical Standards Board Rules provide that: “This report is published by SAE to ad
7、vance 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 therefrom, is the sole responsibility of the user.” SAE reviews each technical report at least
8、every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions. Copyright 2010 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
9、, 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 (outside USA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SAE
10、 values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/AMS2680C AMS 2680C SAE AMS 2680C- 2 -2.2 ASTM Publications: Available from ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959.ASTM E 8 Tension Testing of Metallic Materials
11、ASTM E 8M Tension Testing of Metallic Materials (Metric)ASTM E 1444 Magnetic Particle ExaminationASTM E 1417 Liquid Penetrant ExaminationASTM E 1742 Radiographic Examination2.3 ANSI Publications: Available from American National Standards Institute, Inc., 1430 Broadway, New York, NY 10018.ANSI B46.1
12、 Surface Texture2.4 AIA Publications: Available from National Standards Association, Inc., 5161 River Road, Bethesda, MD 20812.NAS 976 Electron Beam Welding Machine3. TECHNICAL REQUIREMENTS: 3.1 Materials: 3.1.1 Parent Materials: Shall be as specified on the applicable part drawing.3.1.2 Filler Mate
13、rials: When required, filler metal shall be as specified on the part drawing.3.1.3 Cleaning Materials: Cleaning materials, chemical solvents, or etching solutions shall be as specified on the part drawing or in the certified welding procedure.3.2 Equipment: 3.2.1 Electron-Beam Welding Equipment: Sha
14、ll be capable of producing welds meeting the requirements of 3.6 and 3.7. Equipment conforming to NAS 976 is accepted as meeting this requirement.3.2.2 Jigs and Fixtures: All holding fixtures shall be capable of maintaining the desired configuration and tolerances during welding, providing back-up a
15、s required, and allowing required work space between the work piece and the electron gun. Back-up material used to deflect or absorb residual electron-beam energy shall be of the same alloy as the part being welded except that alternate back-up materials may be used when approved by procedure certif
16、ication as in 3.4.2. Tooling within 6 inches (152 mm) of the weld joint shall be made from nonmagnetic materials or be degaussed to acceptable limits (See 3.2.3).AMS 2680C SAE AMS 2680C- 3 -3.2.3 Degaussing: Ferromagnetic materials and tooling shall, prior to welding, be demagnetized to a level esta
17、blished by procedure certification (3.4.2) which prevents electron beam deflections while welding the joint.3.3 Preparation: Joint and surface preparation, prior to welding, shall be as follows and shall be included as part of the approved procedure certification:3.3.1 Joint Preparation: Joints shal
18、l be prepared to conform to requirements specified on the part drawing.3.3.2 Edge Preparation: Edges shall be machined square and parallel to ensure proper fit-up. Joints shall have no rounded-off edges, but shall be deburred after machining. Unless otherwise specified, faying surfaces of joints sha
19、ll have a surface texture not greater than 125 microinches (3.2m), determined in accordance with ANSI B46.1. Witness lines, when specified, shall be applied in accordance with part drawing requirements (See ARP1333 for guidelines). Dry machining is recommended for edge preparation of reactive metals
20、.3.3.3 Weld Start and Run-Off Tabs: Tabs, when used, shall be of the same alloy as the detail parts being welded and shall be cleaned in the same manner as the parts. Tabs shall be integral with the part, either being machined in, or welded to, the part pieces prior to assembly.3.3.4 Surface Prepara
21、tion: Prior to welding surfaces of parts shall be prepared using a suitable cleaning agent and method consistent with the alloys being welded. If solvents are used on titanium alloys, they must be nonhalogenated (See 8.2). Welding shall commence within 40 hours after surface preparation, unless othe
22、rwise permitted or restricted by purchaser.3.3.4.1 Parts, after surface preparation, shall be handled in the joint area with clean, lint-free gloves and shall be covered or otherwise protected to prevent contamination, except during set-up, welding, and inspection.3.3.5 Accessory Equipment Preparati
23、on: Jigs, fixtures, and measuring devices shall be free of scale, grease, protective coatings, oxides, dust, oil, and other foreign material detrimental to the welding process.3.3.5.1 Cleaned surfaces shall be handled only with clean, lint-free gloves.3.3.6 Pre-Weld Fit-Up: Gaps for production weldi
24、ng shall not exceed gap distance used for procedure certification as in 3.4.2. For small diameter electron beams (high voltage guns), a suggested maximum allowable gap is 0.001 inch (0.03 mm). For larger diameter electron beams (low or medium voltage guns), the suggested maximum allowable gaps are 0
25、.001 inch (0.03mm) for material thicknesses up to 0.020 inch (0.51 mm) and 0.005inch (0.13 mm) for thicker material.AMS 2680C SAE AMS 2680C- 4 -3.4 Procedure: 3.4.1 Qualification of Welding Operators: Electron-beam welding shall be performed by certified operators, qualified in accordance with proce
26、dures approved by purchaser.3.4.1.1 Personnel performing welding in accordance with this specification shall be qualified under the cognizance and supervision of the designated welding activity and approved by the cognizant quality control activity. Qualified personnel shall be assigned a stamp with
27、 a number or symbol that shall be used to identify all weldments made by such personnel.3.4.1.2 An operator undergoing qualification testing may weld a certification plate in accordance with 3.4.2 according to a pre-established schedule as part of the test. If the operator successfully qualifies, th
28、e weld procedure shall be considered certified. All parameters used for welding the certification plate shall be recorded in the weld procedure, Table 1.3.4.1.3 Operators certified in accordance with AMS-STD-1595 (as applicable to electron beam welding) shall be considered qualified to weld in accor
29、dance with this specification.3.4.2 Procedure Certification: Prior to production, a separate weld schedule shall be established for each joint and alloy or alloy combination to be welded. The schedule shall be prepared for each penetration weld joint configuration, and for each cosmetic pass configu
30、ration, if required, showing all applicable items listed in Table 1.3.4.2.1 For full penetration weld joints, a test plate conforming to Figure 1 shall be welded in accordance with the prepared weld procedure. Where the test plate of Figure 1 is not an appropriate representation of the parts to be w
31、elded, as in the case of forgings, castings, tubing, or other geometric considerations, the procedure shall be established on actual or simulated parts as agreed upon by purchaser and vendor.3.4.2.2 For any cosmetic pass configurations, a test plate conforming to Figure 2 shall be welded in accordan
32、ce with the prepared weld procedure and submitted for metallurgical examination in accordance with 3.6.2.2. Cosmetic pass configurations shall be made as a bead-on-previously-deposited full-penetration weld. The cosmetic pass configuration test sample may also be taken from a simulated or actual par
33、t as specified by purchaser.3.4.2.3 Test Piece Preparation and Testing: The weld schedule certification test piece (either Figure 1, actual part, or simulated part) shall be of the same material and condition and shall be prepared and cleaned in the same manner as the production part. Welding shall
34、be performed using the same welding position and joint configuration (thickness and angle) representative of that used on the production part. The welding operators ID number shall be marked on each test piece welded for certification. Testing shall be accomplished in accordance with 3.6 and 3.7.3.4
35、.2.4 Upon acceptance of the test piece(s) (either Figure 1, actual part, or simulated part) for either a full-penetration or (Figure 2) a cosmetic-pass weld, the cognizant quality control activity shall certify the weld procedure.AMS 2680C SAE AMS 2680C- 5 -3.4.2.5 Tacking/Locking Passes: A tacking
36、pass may be used to restrict relative motion in the weld assembly prior to the first full penetration pass. Weld schedule certification of a tacking pass is not required provided all evidence of the tack welding is obliterated by the actual weld through fusion.3.4.2.5.1 A tacking pass, other than a
37、full-penetration pass, made with a power density setting substantially reduced from the certified settings, may be used over any portion of the weld joint up to and including the full length of the weld.3.4.2.5.2 A full-penetration tacking pass using certified parameters may be utilized but shall no
38、t exceed 10% of the weld joint length. This locking pass shall terminate in the starting or stopping tabs, when applicable.3.4.2.6 Cosmetic Pass: Cosmetic passes for the purpose of correcting unacceptable underfill conditions may be applied at any time after completion of the initial full-penetratio
39、n pass. Cosmetic passes, if used, shall be certified in accordance with 3.4.2.2.3.4.3 Procedure Recertification: Recertification of weld schedules shall be required for failed test welds and when any change is made to the following parameters:3.4.3.1 When a change is made in base metal composition o
40、r a change is made in thickness in excess of 10% (not applicable to cosmetic-pass-weld configuration).3.4.3.2 When a change is made in joint design (not applicable to cosmetic-pass-weld configuration), but not necessarily after changes in length of diameter of joint.3.4.3.3 When the welding position
41、 (relationship between the gun angle and the work angle) is changed in excess of 10 degrees.3.4.3.4 When a change is made in any one of the machine settings, items 12 and 14 through 20, or in the energy input, item 23 of Table 1.3.4.3.4.1 The use of the beam-deflection switch, item 19 of Table 1, ne
42、ed not be considered when used for the purpose of scanning or beam alignment.3.4.3.5 When the weld machine, weld gun, or filament shape are different from that used to certify the welding procedure.3.4.4 Production Welding: Production parts shall be welded in accordance with the parameters establish
43、ed in the weld procedure certification of 3.4.2.3.4.4.1 Welding Environment: Electron-beam welding shall be performed in a vacuum at a partial pressure not higher than 1 x 10-4 millimeters of mercury. Venting of the chamber after welding shall not occur less than two minutes after completion of weld
44、ing, unless otherwise established in the weld procedure certification.AMS 2680C SAE AMS 2680C- 6 -3.4.5 Rework: A rework shall be a full or partial electron beam penetration weld accomplished subsequent to the full-penetration weld. Rework of imperfections, such as cosmetic passes for correction of
45、underfill or bead appearance improvement, as well as full-penetration passes for correction of a missed joint, and other defects may be accomplished by electron beam welding in accordance with a certified welding schedule. Restarting the electron beam after an arc-out shall not be classified as a re
46、work but the reason, location, and method shall be recorded. Only one reweld is permitted.3.5 Post Treatment: 3.5.1 Finishing: Post weld machining of face or root surfaces, or both shall be as described on the applicable part drawing and/or the certified weld schedule. Post weld blending shall not d
47、ecrease the parent material by more than 10% of the joint thickness, for full penetration welds, or more than 5% of the maximum depth of penetration for partial penetration welds.3.5.2 Heat Treatment: Weldments requiring heat treatment shall be processed in accordance with part drawing requirements.
48、3.6 Properties: Specimens taken from test plates, actual parts, or simulated parts produced for procedure certification as in 3.4.2.1 and 3.4.2.2 shall conform to the following requirements:3.6.1 Tensile Strength: When required, specimens shall conform to and be tested in accordance with ASTM E 8 or
49、 ASTM E 8M. The weld is acceptable when failure occurs at a stress equal to or greater than the minimum tensile strength specified by purchaser. Specimens failing at the bond line of the weld or in the weld metal are acceptable only when examination of the fracture surface at 15X magnification reveals it to be free of defects.3.6.2 Metallurgical Examination for Soundness and Bead Shape: 3.6.2.1 Macro-sections of the weld shall conform to the requirements of 3.7. Sections shall be taken transverse to the weld direction and shall be examined at 3 to 10X magnification. When requ
