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 reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions. Copyright 2012 SAE International All rights reserved. No part of this publication m
3、ay 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 (outside U
4、SA) 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/AMS2431/7B AEROSPACE MATERIAL SPECIFICATION AMS2431/7 REV. B Issued 1988-04 Reaffirmed 1994-0
5、4 Revised 2013-02 Superseding AMS2431/7A Peening Media Ceramic Shot RATIONALE AMS2431/7B results from a Five Year Review and update of this specification and adds coverage for AZB100 ceramic shot. 1. SCOPE 1.1 Purpose The complete requirements for procuring the product shall consist of this document
6、 and the latest issue of the basic specification, AMS2431. 1.2 Application Ceramic shot conforming to this specification is typically intended for use in peening of metal surfaces to impart compressive stresses to these surfaces thereby increasing resistance to fatigue and stress-corrosion cracking.
7、 Generally, ceramic shot may be used where ferrous contamination of the part is undesirable or very hard parts (over 60 HRC) are to be peened for maximum residual compressive stress. 2. APPLICABLE DOCUMENTS See AMS2431. 3. TECHNICAL REQUIREMENTS 3.1 Ceramic shot shall conform to AMS2431 and the requ
8、irements specified herein. 3.2 Composition shall be high quality zirconium oxide and silica. The percentage variation by weight ranges of the main constituents of ceramic shot shall be: TABLE 1 - COMPOSITION Constituent min max Zirconium Oxide 60 70 Silica 28 33 Alumina - 10 Other Constituents, tota
9、l - 3 SAE AMS2431/7B Page 2 of 6 3.2.1 Hardness Hardness shall be measured by the manufacturer at least on mother production batches. User should measure hardness at his discretion or when a counter analysis is required. For AZB850 to AZB150, at least 90% of the readings shall fall within the range
10、of 643 to 785 HV (58 to 63 HRC, for reference only). For AZB100, the mean value of the readings shall fall within the same range of 643 to 785 HV. 3.2.2 Density shall be between 3.60 and 3.95 g/cc, measured at 70F (21C) by a pycnometric method. 3.2.3 Magnetic particles shall not exceed 0.1% by weigh
11、t of the original sample. 3.2.4 Surface Discolorations Not more than 15% of the shot shall show foreign discolorations. A particle shall be considered objectionable for foreign discoloration when more than 25% of its surface area is discolored. 3.2.5 Coatings Foreign materials are not permitted. 3.3
12、 Workmanship 3.3.1 Shape Ceramic shot shall be spherical to ellipsoid in shape. Table 2 shows the maximum percentage of ceramic shot having a sphericity lower than 0.5 and the minimum percentage of ceramic shot having a sphericity of 0.8 and above (true spheres). See Section 8 for definition of sphe
13、ricity. Maximum number of permissible broken or angular beads is shown on column 11 of Table 2. This number shall never exceed 3% of the actual count. See Section 8 for definition of roundness. 3.3.2 Satellites Maximum allowable number of shot with satellites shall be Table 3. See Section 8 for defi
14、nition of satellites. 3.4 Size shall conform to the requirements of Table 2. 3.5 Test Methods and Procedures 3.5.1 Size Classification Sieve analysis shall be determined in accordance with ASTM D 1214. Screens shall be in accordance with U.S. Standard Series described in ASTM E 11. 3.5.2 Composition
15、 shall be measured by the manufacturer at least on mother production batches by x-ray fluorescence or by other method acceptable to purchaser. User should measure composition at his discretion or when a counter analysis is required. 3.5.3 Hardness shall be determined by a Vickers diamond pyramid pen
16、etrator using 1000 gram load in accordance with ASTM E 384 or ASTM C 1327. To avoid fracture of beads, the loads shall be as follows: 200 gram load for AZB100, 500 gram load for AZB150, AZB210 and AZB300 and 1000 gram load for AZB425, AZB600 and AZB850. SAE AMS2431/7B Page 3 of 6 3.5.4 Contamination
17、 3.5.4.1 Magnetic Particle Content shall be determined by slowly sprinkling approximately 1500 gram of the sample ceramic shot on an inclined aluminum tray that is 0.062 inch (1.57 mm) deep by 6 inches (152 mm) wide by 12 inches (305 mm) long. The tray shall be supported by a nonmagnetic frame so th
18、at it is inclined with a 6 inch (152 mm) rise from end to end, (30 degrees from horizontal). Four 1 1 6 inches (25 25 152 mm) bar magnets are positioned against the under surface and crosswise to the inclined tray about the middle of its length. Thickness of tray at magnet location shall not exceed
19、0.062 inch (1.57 mm). Magnets shall be not less than 10 000 Gauss each and arranged so that the magnetic north and south poles alternate. The magnetic particles (iron) that accumulate on the tray as the beads roll down shall be brushed into a preweighed dish. The procedure shall be repeated with the
20、 same 1500 gram sample until all visible magnetic particles are collected. The dish shall be reweighed and the magnetic particle content calculated as a percentage of the total original sample. 3.5.4.2 Surface discolorations shall be determined microscopically using magnification as per 4.1.5. 3.5.5
21、 Shape A visual count shall be made of three fields of at least 100 shot each on the sample prepared as per 4.1.5. 3.5.6 Density Sixty grams of shot, carefully weighed to the nearest 0.1 gram, and previously dried, shall be placed in a 100 mL graduated cylinder containing approximately 50 mL of reag
22、ent water. The resultant volume minus initial volume represents the volume of the shot. 60gDensityShot Volume=TABLE 2 CERAMIC SHOT FOR PEENING SIZES AND SPHERICITY Designation Nominal Sizes, Millimeters Nominal Sizes, Inch Nominal Sizes, Mesh Sieve Size, Millimeters Maximum 0.5% Retained Sieve Size,
23、 Millimeters Maximum 5% Retained Sieve Size, Millimeters Maximum 10% Passing Sieve Size, Millimeters Maximum 3% Passing Minimum % of Shot W/Sphericity 0.8 and Above (True Spheres) Maximum Number of Shot with Sphericity Below 0.5 per Square Centimeter Number Broken or Angular Beads Acceptable per Squ
24、are Centimeter AZB850 0.85/1.18 0.033/0.047 16/20 1.400 1.180 0.850 0.710 65 4 2 AZB600 0.6/0.85 0.024/0.033 20/30 1.000 0.850 0.600 0.425 65 8 4 AZB425 0.425/0.6 0.017/0.024 30/40 0.710 0.600 0.425 0.300 70 14 8 AZB300 0.300/0.425 0.012/0.017 40/50 0.500 0.425 0.300 0.250 70 27 15 AZB210 0.212/0.30
25、0 0.008/0.012 50/70 0.355 0.300 0.212 0.180 80 55 20 AZB150 0.150/0.212 0.006/0.008 70/100 0.250 0.212 0.150 0.125 80 300 65 AZB100 0.100/0.150 0.004/0.006 100/140 0.180 0.150 0.106 0.063 80 600 90 SAE AMS2431/7B Page 4 of 6 TABLE 3 CERAMIC SHOT WITH SATELLITES Designation Maximum Number of Shot wit
26、h Satellites per Square Centimeter Maximum Number of Shot with 3 or More Satellites per Square Centimeter AZB850 8 3 AZB600 13 6 AZB425 38 12 AZB300 66 21 AZB210 125 40 AZB150 174 50 AZB100 348 100 4. QUALITY ASSURANCE PROVISIONS See AMS2431 and the following: 4.1 Sampling Samples for testing shall
27、be representative of each production batch. Any 25 kg container from each production batch is representative of the production batch. The sampling method is to select randomly a 25 kg container from each production batch and blend the contents. Test samples can then be obtained by successive passes
28、through a sample splitter until the test samples quantity 150 Q 300 g is obtained. Two samples of approximately 200 grams each shall be split to the following test quantities. 4.1.1 Composition Not less than two samples from each shipment. 4.1.2 Hardness At least 10 micro-hardness readings shall be
29、made with no more than 1 impression from any one shot. 4.1.3 Specific Gravity Two 60 gram samples for specific gravity determination. 4.1.4 Size Two representative samples of 60 grams minimum weight. 4.1.5 Shape Sphericity, roundness and satellites are measured by an actual counting of a one layer f
30、ield of ceramic beads, using minimum area to be counted as follows: SAE AMS2431/7B Page 5 of 6 TABLE 4 MINIMUM MAGNIFICATION plastic or glass for example. The product to be analyzed shall be taken from a 50 g representative sample of the batch. Part of this sample shall be then transferred onto a sa
31、mple strip by pouring the sample onto the strip, or dipping the strip into the sample container. This shall be done until the strip is fully covered with a single layer of beads. Three different fields chosen at random on each strip with at least 100 shots in each field shall be used to make the mea
32、surements. The results for 100 shots in each of the 3 fields shall be added and then divided by the corresponding area in Table 4 to give the results per square centimeter. These results shall be compared to Table 2 and Table 3. 4.1.5.1 A mechanical method of inspection for shape is permitted provid
33、ed that it can be correlated to the optical method and is acceptable to purchaser. 5. PREPARATION FOR DELIVERY See AMS2431 and the following: 5.1 Packaging and Identification Shot shall be packaged in 25 kg units. 6. ACKNOWLEDGMENT See AMS2431. 7. REJECTIONS See AMS2431. 8. NOTES See AMS2431 and the
34、 following: 8.1 Definitions 8.1.1 Batches: A mother production batch is greater in quantity than a production batch (i.e. multiple of production batches). A production batch is 1000 kgs. SAE AMS2431/7B Page 6 of 6 8.1.2 Sphericity (Ref. 3.3.1): It refers to the aspect ratio of short to long axes of
35、the hypothetical ellipse that would contain the actual image of the ceramic bead as seen through a microscope. Example of shot with sphericity below 0.5: 8.1.3 Roundness (Ref. 3.3.1): It refers to the relative angularity of grain corners, the ceramic shot having round and smooth surfaces. Scored, br
36、oken or angular particles are those that would present sharp or angular surfaces when impacted, causing metal removal or unsatisfactory or irregular finishes. 8.1.4 Satellites (Ref. 3.3.2): Satellites are particles attached to the surface of a bead. D = Bead diameter d = Satellite diameter A satellite is counted if all of the following conditions apply: d 0.25 D d 0.5 mm in the magnified view PREPARED BY AMS COMMITTEE “B”
