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 theref
2、rom, 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 2010 SAE International All rights reserved. No part of this publication ma
3、y 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 US
4、A) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/AMS2431/2EAEROSPACEMATERIALSPECIFICATIONAMS2431/2 REV. E Issued 1988-04 Revised 2010-12 Superse
5、ding AMS2431/2D Peening Media (ASH) Cast Steel Shot, High Hardness (55 to 62 HRC) RATIONALEAMS2431/2E was issued to clarify Table 4 and paragraph 3.9. 1. SCOPE 1.1 The complete requirements for procuring the product shall consist of this document and the latest issue of the basic specification, AMS2
6、431. 1.2 Application Cast steel shot, high hardness, have been used typically in peening metal surfaces to impart compressive stresses to these surfaces thereby increasing resistance to fatigue and stress-corrosion cracking, but usage is not limited to such applications. Generally, high hardness cas
7、t steel shot is used on parts of hardness 50 HRC or over. 2. APPLICABLE DOCUMENTS The issue of the following documents in effect on the date of the 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
8、specific document issue is specified. When the referenced document has been cancelled and no superseding document has been specified, the last published issue of that document shall apply. 2.1 SAE Publications Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel:
9、877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org.AMS2431 Peening Media, General Requirements 3. TECHNICAL REQUIREMENTS 3.1 Cast steel shot, high hardness, shall conform to AMS2431 and the requirements specified herein. Copyright SAE International Provided by IHS under
10、license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AMS2431/2E Page 2 of 73.2 Composition shall conform to the percentages by weight shown in Table 1, determined in accordance with ASTM E 350. TABLE 1 - COMPOSITION Element min maxCarbon 0.80 1.20Man
11、ganese (3.2.1) - 1.20Silicon 0.40 1.50Phosphorus - 0.05Sulfur - 0.053.2.1 Minimum manganese content shall conform to the minimum percentage by weight shown in Table 2.TABLE 2 - MINIMUM MANGANESE CONTENT Shot Size Wt PercentASH-70 to ASH-130 0.35 ASH-170 and ASH-190 0.50 ASH-230 and up 0.60 3.3 Hardn
12、ess Not less than 90% of the readings, using a microhardness tester with a minimum 500 gram load, shall fall within the range of 55 to 62 HRC, or equivalent, determined in accordance with ASTM E 384. See 8.4. 3.4 Microstructure shall exhibit uniformly tempered martensite with fine, well-distributed
13、carbides. 3.5 Density shall be not less than 7.0 grams per milliliter, determined in accordance with 3.9.2. 3.6 Contamination Shot shall be clean and free of dirt, grit, oil, or grease. 3.7 Quality requirements shall conform to 3.7.1, 3.7.2, 3.7.3, and 3.7.4, determined in accordance with 3.9.3. 3.7
14、.1 Acceptable Shapes Shapes in accordance with Figure 1 are acceptable. 3.7.2 Marginal Shapes Shapes conforming to Figure 2 are permissible to the extent specified in Table 3. 3.7.3 Unacceptable Shapes Shapes conforming to Figure 3 are permissible to the extent specified in Table 3. 3.7.4 Internal D
15、efects No more than 15% of the particles, by count, may exhibit cracks, hollows, or shrinkage. See Figure 4. Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AMS2431/2E Page 3 of 7TABLE 3 - SHAPE
16、REQUIREMENTS Shot Size Area per Field Square Inch (mm2)Number of FieldsViewedNumber of Marginal Particles All Fields (1), max Number of UnacceptableParticles, All Fields (2), maxASH 930 1 (645) 1 8 2 ASH 780 1 (645) 1 12 2 ASH 660 1 (645) 1 16 3 ASH 550 1 (645) 1 20 4 ASH 460 1 (645) 1 28 5 ASH 390
17、1 (645) 1 39 7 ASH 330 0.25 (161) 1 14 3 ASH 280 0.25 (161) 1 20 4 ASH 230 0.25 (161) 1 14 5 ASH 190 0.25 (161) 1 20 7 ASH 170 0.25 (161) 1 28 10 ASH 130 0.0625 (40) 1 10 4 ASH 110 0.0625 (40) 1 14 5 ASH 70 0.0625 (40) 1 39 13 Notes: (1) Maximum number of marginal shapes is approximately 3% of the t
18、otal number of particles viewed for ASH 70 to ASH 230, 6% for ASH 280 to ASH 550, and 7% for ASH 660 to ASH 930. (2) Maximum number of unacceptable shapes is approximately 1% of the total number of particles viewed. 3.8 Size shall conform to the requirements of Table 4, determined in accordance with
19、 3.9.1. TABLE 4 - SCREENING REQUIREMENTS Shot Size 0% max 2% max onScreen50% max Cumulative onScreen90% min Cumulative on Screen98% min Cumulative onScreenASH 930 5 (0.157) 6 (0.132) 7 (0.111) 8 (0.0937) 10 (0.0787) ASH 780 6 (0.132) 7 (0.111) 8 (0.0937) 10 (0.0787) 12 (0.0661) ASH 660 7 (0.111) 8 (
20、0.0937) 10 (0.0787) 12 (0.0661) 14 (0.0555) ASH 550 8 (0.0937) 10 (0.0787) 12 (0.0661) 14 (0.0555) 16 (0.0469) ASH 460 10 (0.0787) 12 (0.0661) 14 (0.0555) 16 (0.0469) 18 (0.0394) ASH 390 12 (0.0661) 14 (0.0555) 16 (0.0469) 18 (0.0394) 20 (0.0331) ASH 330 14 (0.0555) 16 (0.0469) 18 (0.0394) 20 (0.033
21、1) 25 (0.0278) ASH 280 16 (0.0469) 18 (0.0394) 20 (0.0331) 25 (0.0278) 30 (0.0234) ASH 230 18 (0.0394) 20 (0.0331) 25 (0.0278) 30 (0.0234) 35 (0.0197) ASH 190 20 (0.0331) 25 (0.0278) 30 (0.0234) 35 (0.0197) 40 (0.0165) ASH 170 25 (0.0278) 30 (0.0234) 35 (0.0197) 40 (0.0165) 45 (0.0139) ASH 130 30 (0
22、.0234) 35 (0.0197) 40 (0.0165) 45 (0.0139) 50 (0.0117) ASH 110 35 (0.0197) 40 (0.0165) 45 (0.0139) 50 (0.0117) 80 (0.0070) ASH 70 40 (0.0165) 45 (0.0139) 50 (0.0117) 80 (0.0070) 120 (0.0049) Notes: (1) Nominal Size = 90% Screen Opening (e.g.: Nominal size of ASH 230 shot is 0.0234 diameter. Copyrigh
23、t SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AMS2431/2E Page 4 of 73.9 Test Methods and Procedures 3.9.1 Size Screening Test The size of shot, specified in 3.8, shall be determined by using a 100-gram
24、 (approximately) sample and screening as follows: The required standard testing sieves in accordance with ASTM E 11 shall be nested in ascending order with a pan on the bottom. The 100-gram sample shall be poured onto the top sieve and the nested sieves shall be placed in a rotating and tapping type
25、 of shaking machine. The rotating speed shall be 270 to 300 rpm and the tapping speed shall be 140 to 160 taps per minute. Shaking and tapping shall be continued for 5 minutes 5 seconds for sieves 30 mesh and coarser and 10 minutes 5 seconds for sieves finer than 30 mesh. After shaking, the percenta
26、ge of shot on each screen shall be determined by weighing the shot retained on each screen. 3.9.2 Density Approximately 60 grams of shot, previously dried and weighed to the nearest 0.1 gram, shall be placed in a 100 mL graduated cylinder containing 50 mL of ethanol or methanol. The total volume min
27、us 50 mL represents the volume of the shot. The density is determined using Equation 1. Density = Shot weight (grams) Shot volume (ml) (Eq. 1) 3.9.3 Shape Visual evaluation, at a magnification of 10 to 30X shall be performed using the areas and number of fields specified in Table 3 for each respecti
28、ve shot size. 3.9.4 Microstructure The sample shall be mounted, polished, and etched with 2% Nital, or other suitable etchant, and examined using a microscope at approximately 500X magnification. 4. QUALITY ASSURANCE PROVISIONS In accordance with AMS2431 and the following. 4.1 Sampling and Testing T
29、wo samples of approximately 800 grams each shall be selected from separate containers chosen at random from each lot. Each sample shall be split using a sample splitter to test quantities as follows: 4.1.1 Composition Not less than two samples from each lot shall be evaluated. 4.1.2 Hardness A minim
30、um of 20 microhardness readings shall be made from each sample with no more than one impression on any one shot. The hardness test impression shall be located approximately midway between the surface and the center of the shot. 4.1.2.1 Samples for microhardness testing shall be prepared by encapsula
31、ting a single layer of shot in a plastic mount and polishing down to nominal half spheres. 4.1.3 Microstructure The sample used for hardness testing may also be used for microstructure evaluation. Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or netw
32、orking permitted without license from IHS-,-,-SAE AMS2431/2E Page 5 of 74.1.4 Density Two 60-gram samples shall be evaluated for density determination. 4.1.5 Size Two representative samples of not less than 100 grams each shall be used for size evaluation. 4.1.5.1 Alternative methods for size evalua
33、tion may be utilized provided that they can be correlated to the sieve analysis method and are acceptable to purchaser. 4.1.6 Shape A representative sample shall consist of an amount of shot, in one layer, which completely fills the areas specified in Table 3. The number of areas, or fields of view,
34、 evaluated at 10 to 30X magnification for each shot size shall be as indicated in Table 3. See 3.9.3. 4.1.6.1 Alternative methods of inspection for shape are permitted provided that they can be correlated to the optical method and are acceptable to purchaser. 4.1.7 Internal Defects The mount prepare
35、d for microhardness testing shall be also used to evaluate defects. A minimum of 100 particles shall be evaluated for defects. Internal defects (Figure 4) include cracks, hollows, and shrinkage. A maximum of 10%, by count, of particles evaluated may contain cracks. A maximum of 10%, by count, of par
36、ticles evaluated may contain hollows. A maximum of 10%, by count, of particles evaluated may contain shrinkage. A maximum total of 15%, by count, of particles evaluated may exhibit any defects, cracks, hollows, or shrinkage. See 3.7.4. Particles with more than one defect shall be counted only once i
37、n the total. A magnification of 10 to 30X shall be used for evaluation of defects. 5. PREPARATION FOR DELIVERY In accordance with AMS2431 and the following: 5.1 Packaging and Identification Steel shot shall be packaged in 40 to 55 pound (18 to 25 kg) units in plastic coated bags or pails. 6. ACKNOWL
38、EDGMENT In accordance with AMS2431. 7. REJECTIONS In accordance with AMS2431. 8. NOTES 8.1 See AMS2431 and the following. 8.2 Terms used in AMS are clarified in ARP1917 and as follows. 8.2.1 Cracked shot is one that exhibits a linear discontinuity with length greater than three times its width and l
39、ength greater than 20% of the particle diameter. 8.2.2 Hollow is a void with an area that is greater than 10% of the area of the shot particle. Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AMS
40、2431/2E Page 6 of 78.2.3 Shrinkage is an internal cavity with an irregular dendritic surface and is greater than 40% of the area of the shot particle area. 8.3 A change bar (l) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial ch
41、anges, have been made to the previous issue of this document. An (R) symbol to the left of the document title indicates a complete revision of the document, including technical revisions. Change bars and (R) are not used in original publications, nor in documents that contain editorial changes only.
42、 8.4 Hardness conversions to Rockwell C values for metals are presented in ASTM E 140. 8.5 Dimensions and properties in inch/pound units and the Fahrenheit temperatures are primary; dimensions and properties in SI units and the Celsius temperatures are shown as the approximate equivalents of the pri
43、mary units and are presented only for information. PREPARED BY AMS COMMITTEE “B” AND AMEC-SE Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AMS2431/2E Page 7 of 7FIGURE 1 - ACCEPTABLE SHAPES FIGURE 2 - MARGINAL SHAPES FIGURE 3 - UNACCEPTABLE SHAPES FIGURE 4 - INTERNAL DEFECTS Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
