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 2016 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:/standards.sae.org/AMS2590A AEROSPACE MATERIAL SPECIFICATION AMS2590 REV. A Issued 2010-12 Revised 2016-11Supersed
5、ing AMS2590 Rotary Flap Peening of Metal Parts RATIONALE AMS2590A results from a Five-Year Review and update of this specification with changes to paragraphs 1.2, 3.1.1, 3.1.4, 3.3.6, 3.4.1.1, 3.4.3, 3.5, 3.5.1, 3.6, 3.8, 4.3.1, 4.3.2, Figure 1, Figure 2, Figure 3, and Figure 4. 1. SCOPE 1.1 Purpose
6、 This specification covers procedures and requirements for peening of metal parts with portable, bonded-shot, rotary flap assemblies in accordance with AS2592. The principles of rotary flap peening are similar to conventional shot peening, except conversion of arc height values using the magnetic Al
7、men test strip holder is required for intensity determination. 1.2 Application This process is normally used for peening or local repeening of blemished areas, straightening and reshaping of parts, for plating adhesion testing, and for cosmetic surface restoration of peened parts, but usage is not r
8、estricted to these applications. Use of rotary flap peening requires customer approval when used to replace manual or automated shot peening. Conformance with AMS2430 is required to the extent specified herein. 2. APPLICABLE DOCUMENTS The issue of the following documents in effect on the date of the
9、 purchase order forms a part of this specification 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 cancelled and no superseding document has been specified, the last publ
10、ished issue of that document shall apply. SAE INTERNATIONAL AMS2590A Page 2 of 14 2.1 SAE Publications Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or +1 724-776-4970 (outside USA), www.sae.org. AMS2430 Shot Peening, A
11、utomatic AS2592 Flap Assemblies, Rotary Flap Peening SAE J442 Test Strip, Holder, and Gage for Shot Peening SAE J443 Procedures for Using Standard Shot Peening Almen Strip SAE J2277 Shot Peening Coverage Determination 3. TECHNICAL REQUIREMENTS 3.1 Equipment 3.1.1 Rotary Tools Pneumatic or electrical
12、ly powered rotary tools shall be used which can accommodate mandrels described in AS2592. The rotary tool shall be capable of operating at speeds that will produce the required intensity. Actual operational speed of the rotary tool is dependent on the desired intensity and is established in 3.4.1. O
13、nce the operational speed is established the rotary tool shall be capable of maintaining a constant speed within 100 revolutions per minute (RPM) while the flap assembly is in contact with a work piece or Almen test strip. 3.1.2 Flap Assemblies Flap assemblies including mandrels and flaps shall conf
14、orm to AS2592. 3.1.3 Almen Test Strips and Gage Almen test strips and gage shall conform to SAE J442. Almen test strips shall be A, C, or N type as specified by the Purchaser. 3.1.4 Test Strip Holder A magnetic strip holder conforming to Figure 1 shall be used. It shall consist of a nonmagnetic mate
15、rial block with three permanent magnets loosely recessed into the top side for the purpose of positioning an Almen test strip. The magnets and their fasteners shall be adjusted to allow the strip to lie flat on the holder. The magnets shall be allowed to move while maintaining contact with the Almen
16、 test strip while peening. A backstop shall be located as shown in Figure 1 to prevent the Almen test strip from moving out of position. An optional backstop may be added at the opposite end of the Almen test strip to provide a level approach surface to the test strip. This will prevent the shot on
17、the flaps from hitting the exposed end of the test strip which may dislodge them from the flap. The form of the back stops are not restricted as long as they function as outlined above. The height of the backstops may vary to suit the use of the different Almen test strip thicknesses. The bottom sur
18、face of the holder shall be faced with non-skid material. Supplier shall furnish certification that the magnetic strip holder meets this specification. 3.2 Part Preparation 3.2.1 Customer Responsibility The customer shall provide all parts to the supplier meeting the following criteria: Areas of par
19、ts to be peened shall be within dimensional requirements and surface finish requirements, all fillets shall be properly formed, all burrs shall be removed, all heat treatments shall be completed, all non-destructive testing shall be completed, all edges and corners to be peened shall be radiused or
20、chamfered, and all coatings removed. SAE INTERNATIONAL AMS2590A Page 3 of 14 3.2.2 Cleaning and Stripping Unless otherwise specified, all areas shall be cleaned by methods that are not physically or chemically damaging. Procedures for stripping coatings shall be as specified or approved by the cogni
21、zant engineering organization. All parts shall be clean and dry prior to peening. 3.2.3 Masking Areas of the part where peening is prohibited shall be suitably masked or protected if within area of possible flap contact. 3.3 Peening Intensity Peening intensity shall be determined from a saturation c
22、urve in accordance with 3.3.2. The saturation curve developed intensity is limited to each individual operator and specific equipment, flapper size, and test strip type. 3.3.1 Arc Height Conversion Strip arc height measurements obtained using the magnetic strip holder shall be converted to the value
23、s equivalent to those that would be obtained using the SAE J442 strip holder using Figures 2A, 2B, 2C, or 2D. The figures have conversion graphs and Tables for A and N strips. Only the converted arc heights shall be used for data points on saturation curves. Any conversions for C test strips shall b
24、e provided by the cognizant engineering organization prior to use. 3.3.2 Intensity Determination Methods Intensity shall be determined by either of the two methods below. The SAE J443 10% rule method is preferred, but the Almen Test Strip Coverage method is permitted. 3.3.2.1 SAE J443 10% Rule Metho
25、d Intensity is determined from a saturation curve with the converted arc height at the first point whose time when doubled produces an arc height increase of 10% per SAE J443. 3.3.2.2 Almen Test Strip Coverage Method For this method a saturation curve is developed by plotting converted arc heights a
26、nd strip coverage versus time. Intensity is determined as the converted arc height of the saturation curve test strip at the time when it reaches full coverage as determined by the methods in SAE J2277 and 3.3.2.7. 3.3.3 Number of Test Strips Regardless of which intensity method is used, only one Al
27、men test strip is required for the entire saturation curve. 3.3.3.1 Gage and Test Strip Procedure The single test strip shall be used to zero the gage which shall conform to SAE J442. In using the gage, the central portion of the side of the test strip that will not be peened shall be placed against
28、 the indicator stem of the gage. The Almen test strip shall be attached to the magnetic strip holder so that the surface of the strip which contacted the gage shall be facing the magnets. The end of the test strip shall contact the backstop as shown in Figure 1. 3.3.3.2 New Flap Preparation New flap
29、s shall be examined to confirm that no resin coating exists over the shot prior to use. If a coating exists, the flap shall be conditioned by operation against an abrasive paper or a hard surface to remove the coating. The resin coating, if not removed, will cushion the impacts against the test stri
30、p and prevent peening. 3.3.4 Used Flap Examination Used flaps shall be examined for shot loss. The loss of shot will affect coverage time, but not intensity. For new job start, it is recommended that the flap be replaced if it has more than two shot missing on one side. SAE INTERNATIONAL AMS2590A Pa
31、ge 4 of 14 3.3.5 Almen Test Strip Coverage Area Peening of the extreme ends of Almen test strips is not necessary. However, uniform coverage of at least the central 2 inches of length is essential to ensure accurate arc height measurement across the Almen gage 1.25 inch support ball distance. 3.3.6
32、Intensity Verification Intensity verification is accomplished by peening one Almen test strip for the intensity time “T” of the saturation curve accepted at the initial intensity determination (see 3.3.2) using the same parameters, operator and equipment. Intensity verification is acceptable if the
33、converted Almen test strip arc height is within 0.0015 inch (0.038 mm) of the original intensity arc height and within the required intensity range. 3.4 Process Preparation 3.4.1 Establishment of Tool Speed To achieve the required peening intensity, the speed necessary for the flap equipment may be
34、estimated by referring to Figure 3. This shall be a first estimate that shall be confirmed or adjusted by generation of a saturation curve. 3.4.1.1 Verification of Tool Speed All RPM measurements shall be verified with a tachometer, stroboscope except when a closed loop RPM controller is used. Tool
35、speed shall be verified at the actual worksite in the same conditions/configuration as the part being peened. Tool speed shall be verified prior to: the creation of the saturation curve, verification of the intensity and application of the peening process to any single work area. Elapsed time betwee
36、nt tool speed verificaiton shall not exceed 60 minutes. 3.4.2 Peening of Holes (1/2 to 1-1/4 inch diameter) The required tool speed shall be established by first determining the speed required to achieve the required intensity on a flat surface and then multiplying by the hole size factors shown in
37、Figure 4. Flap width may be trimmed to accommodate hole depth. 3.4.2.1 Holes to Inch Diameter Flap size of 9/16 x 1 inch shall be used. 3.4.2.2 Holes 3/4 to 1-1/4 Inch Diameter Flap size of 9/16 x 1-1/4 inch shall be used. 3.4.3 Flap Operation The flap assembly shall be moved over the surface being
38、peened with longitudinal sweeps and transverse oscillation, i.e., circular motion to provide uniform surface coverage. Flap deflection (standoff distance from the bottom of mandrel to part surface) shall be between 0.05 inch and 0.150 inch as determined by the operator so as to be comfortable, susta
39、inable and effective. No attempt shall be made to force uniformity of the parameters chosen by the operators as they are operator-specific. Proper flap deflection will be found to be the easiest position to maintain by a given individual operator. 3.5 Coverage Parts shall be peened to the extent spe
40、cified on the engineering drawing. Coverage shall be verified by visual inspection in accordance with SAE J2277 at a magnification of 5X to 30X. Visual examination shall show uniform and complete overlapping of impressions. Holes shall be inspected with a suitable optical instrument. SAE INTERNATION
41、AL AMS2590A Page 5 of 14 3.5.1 Peening Time The area to be peened shall be peened in increments of time and visually inspected for coverage until full coverage is achieved. Coverage time is a function of part material hardness. Soft parts will receive larger peening dents and will cover faster than
42、harder parts. For coverage requirements greater than 100%, the time to reach full coverage of a peened area shall be determined and then multiplied by the greater coverage percentage for total peening time. 3.6 Post Peening Operations Post peening operations including temperature exposure, surface f
43、inish improvement and protection from corrosion shall be in accordance with AMS2430. 3.7 Qualification of Peening Operators 3.7.1 Qualification Tests Qualification testing of peening operators shall consist of proving capability of peening technique, intensity determination, and part peening procedu
44、res. The operator shall demonstrate proper rotary tool motion and consistent flap deflection (standoff distance) techniques to fulfill the requirements of 3.7.1.1 through 3.7.1.3. 3.7.1.1 Intensity Development The operator shall demonstrate proper Almen test strip and Almen gage handling including g
45、age zeroing or prebow compensation and intensity determination from saturation curves. 3.7.1.2 Intensity Determination and Verification A saturation curve shall be considered satisfactory when the operator reproduces an intensity value (intensity verification) from a saturation or saturation coverag
46、e curve that the operator has previously accomplished within 0.0015 inch (0.038 mm) and within the required intensity range. In case of failure to reproduce the intensity verification within that limit, the operator shall be allowed only one retest. Test failure may require retraining or result in d
47、isqualification and must requalify again per 3.7.1. 3.7.1.3 Part Peening Qualification The peening operator shall satisfactorily peen a sample part representative of those commonly peened to demonstrate coverage. 3.7.1.4 Operator Qualification Record The peening facility is responsible for retaining
48、 a written record of the peening operators qualification testing for each intensity and specific equipment, flapper size, and test strip type. Retention period shall be five years minimum. 3.7.1.5 Status Maintenance Qualified status of operators shall be maintained by either maintaining record of co
49、ntinued satisfactory workmanship or by successful re-qualification testing (3.7.1) not greater than every six months. Periodic re-qualification will not be required for operators when records indicate a satisfactory level is being maintained in production peening. 3.8 Tolerances Tolerances shall be in accordance with AMS2430. SAE INTERNATIONAL AMS2590A Page 6 of 14 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for Process
