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 2015 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:/www.sae.org/technical/standards/AMS2304B AEROSPACE MATERIAL SPECIFICATION AMS2304 REV. B Issued 1991-01 Revised 2
5、010-08 Reaffirmed 2015-05 Superseding AMS2304A Steel Cleanliness, Special Aircraft-Quality Magnetic Particle Inspection Procedure RATIONALE AMS2304B has been reaffirmed to comply with the SAE five-year review policy. 1. SCOPE 1.1 Purpose This specification covers steel cleanliness requirements in in
6、ch/pound units for special aircraft-quality ferromagnetic steels, including hardenable corrosion resistant steels, by magnetic particle inspection methods. This specification contains sampling, sample preparation, inspection procedures and cleanliness rating criteria (See 8.2). 1.1.1 The metric vers
7、ion, MAM2304, has been cancelled. The SI units have been included in this specification, but the inch/pound units are primary (See 8.7) 1.2 Application This procedure has been used typically for the cleanliness evaluation of blooms, billets, tube rounds, stock for forging or flash welded rings, slab
8、s, bars, sheet, plate, tubing, and extrusions used in fabricating highly stressed parts where very strict magnetic particle inspection standards are used in final inspection of such parts, but may be used for qualification of a heat, melt or lot of steel. 1.2.1 Product qualified to this specificatio
9、n is not recommended for use in parts where the high transverse properties of vacuum-arc-remelted or electroslag remelted steel are required (See 8.4). 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 e
10、xtent 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 published issue of that document shall apply. 2.1 ASTM Publicat
11、ions Available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, www.astm.org. ASTM E 10 Brinell Hardness of Metallic Materials ASTM E 1444 Magnetic Particle Testing 2.2 ANSI Publications Available from American National Standards Ins
12、titute, 25 West 43rd Street, New York, NY 10036-8002, Tel: 212-642-4900, www.ansi.org. ANSI B46.1 Surface Texture 3. TECHNICAL REQUIREMENTS 3.1 Specimen Preparation 3.1.1 Heat Qualification Sampling shall be in accordance with 4.3.1. Samples shall be converted into test specimens in accordance with
13、3.1.3. 3.1.2 Product Qualification Product from a heat not qualified based on sampling as in 4.3.1 shall be sampled in accordance with 4.3.2. Samples shall be converted into test specimens in accordance with 3.1.3. 3.1.3 Working and Rough Machining 3.1.3.1 Solid Product 12 Inches (305 mm) and Over i
14、n Nominal Diameter or Distance Between Parallel Sides A quarter section shall be cut from the sample sufficiently oversize that the center of the original sample will be approximately on the surface of the specimen after generating to test size. The quartered section shall then be forged to a 3 to 6
15、 inch (76 to 152 mm) round or square, maintaining the axis of the forging approximately parallel to the original direction of rolling. As an alternate method, the full section may be rolled or forged to a 6-inch (152-mm) round or square and an oversize quarter obtained as in 3.1.3.3. Specimens shall
16、 be rough machined to a “one-step” straight cylinder nominally 5 inches (127 mm) long. Minimum stock removal shall be consistent with the machining allowance specified in 3.1.4.1. 3.1.3.2 Solid Product Over 6 to 12 Inches (152 to 305 mm), Exclusive, in Nominal Diameter or Distance Between Parallel S
17、ides Except Slabs and Plates A quarter section shall be cut from each sample sufficiently oversize that the center of the original sample will be approximately on the surface of the specimen after generating to test size. The quarter section shall be converted into a test specimen by machining, or f
18、orging and machining, to a 3 to 6 inch (76 to 152 mm) round or square. Specimens shall be rough machined to a “one-step” straight cylinder nominally 5 inches (127 mm) long. Minimum stock removal shall be consistent with the machining allowance specified in 3.1.4.1. 3.1.3.3 Solid Product 6 Inches (15
19、2 mm) and Under in Nominal Diameter or Distance or Distance Between Parallel Sides Except Flat Bars, Slabs, and Plates A quarter section shall be cut from each sample sufficiently oversize that the center of the original sample will be approximately on the surface of the specimen after generating to
20、 test size. The quarter section shall be converted into a test specimen by machining to a “one-step” straight cylinder nominally 5 inches (127 mm) long. Minimum stock removal shall be consistent with the machining allowance specified in 3.1.4.1. SAE INTERNATIONAL AMS2304B Page 2 of 11_ 3.1.3.3.1 As
21、an alternate method, a stepdown specimen may be generated from the full cross-section in equal length circumferential steps as shown in Table 1. TABLE 1A - STEPDOWN SPECIMENS CYLINDRICAL (INCH/POUND UNITS) Nominal Diameter or Distance Between Parallel Sides Inches Step LengthInches Step 1 Diameter S
22、tep 2 Diameter Step 3 Diameter Step 4 Diameter Step 5 Diameter 0.250 to 0.500, incl 5.000 D - - - - Over 0.500 to 0.750, incl 2.500 D 2/3D - - - Over 0.750 to 1.000, incl 1.665 D 3/4D 1/2D - - Over 1.000 to 1.500, incl 1.250 D 4/5D 3/5D 2/5D - Over 1.500 1.000 D 4/5D 3/5D 2/5D 1/5D D = Original diam
23、eter or distance between parallel sides minus machining stock removed. TABLE 1B - STEPDOWN SPECIMENS CYLINDRICAL (SI UNITS) Nominal Diameter or Distance Between Parallel Sides Millimetters Step Length Millimeters Step 1 Diameter Step 2 Diameter Step 3 Diameter Step 4 Diameter Step 5 Diameter 6.35 to
24、 12.70, incl 127.0 D - - - - Over 12.70 to 19.05, incl 63.50 D 2/3D - - - Over 19.05 to 25.40, incl 42.29 D 3/4D 1/2D - - Over 25.40 to 38.10, incl 31.75 D 4/5D 3/5D 2/5D - Over 38.10 25.40 D 4/5D 3/5D 2/5D 1/5D D = Original diameter or distance between parallel sides minus machining stock removed.
25、3.1.3.4 Flat Bars Specimens nominally 5 inches (127 mm) long shall be rough machined to equal-length steps across the width of the specimen, in accordance with Table 2, allowing 20% of the thickness or 0.100 inch (2.54 mm), whichever is less, for minimum stock removal. Allowance of 0.010 inch (0.25
26、mm) shall be made for finish machining. TABLE 2A - STEPDOWN SPECIMENS - FLAT BARS (INCH/POUND UNITS) Nominal Thickness Inches Step Length Inches Step 1 Thickness Step 2 Thickness Step 3 Thickness Step 4 Thickness Step 5 Thickness Up to 0.250, incl 5.000 T - - - - Over 0.250 to 0.500, incl 2.500 T 2/
27、3T - - - Over 0.500 to 1.000, incl 1.250 T 3/4T 1/2T 1/4T - Over 1.000 1.000 T 4/5T 3/5T 2/5T 1/5T T = Original nominal thickness minus machining stock removed. SAE INTERNATIONAL AMS2304B Page 3 of 11_ TABLE 2B - STEPDOWN SPECIMENS - FLAT BARS (SI UNITS) Nominal Thickness Millimeters Step Length Mil
28、limeters Step 1 Thickness Step 2 Thickness Step 3 Thickness Step 4 Thickness Step 5 Thickness Up to 6.35, incl 127.00 T - - - - Over 6.35 to 12.70, incl 63.50 T 2/3T - - - Over 12.70 to 25.40, incl 31.75 T 3/4T 1/2T 1/4T - Over 25.40 25.40 T 4/5T 3/5T 2/5T 1/5T T = Original nominal thickness minus m
29、achining stock removed. 3.1.3.5 Slabs or Plates A straight cylindrical or rectangular specimen shall be machined, or forged and machined, from each slab or plate tested. The specimen shall be taken essentially parallel to the direction of rolling at the center of the slab or plate width and thicknes
30、s and shall be nominally 5 inches (127 mm) in length, and not more than 4 inches (102 mm) in final diameter or thickness. 3.1.3.5.1 Product Up to 4 Inches (102 mm), Inclusive, in Nominal Thickness A straight cylindrical specimen shall represent the full thickness consistent with the machining allowa
31、nce specified in 3.1.4.1. 3.1.3.5.2 Product Over 4 to 8 Inches (102 to 203 mm), Inclusive, in Nominal Thickness A straight cylindrical specimen shall represent surface to mid-thickness consistent with the machining allowance specified in 3.1.4.1. 3.1.3.5.3 Product Over 8 Inches (203 mm) in Nominal T
32、hickness A straight cylindrical specimen shall be taken so that the axis is approximately midway between the surface and mid-thickness, and shall have a diameter equal to one-third the nominal thickness of the section. 3.1.3.6 Tubing 3.1.3.6.1 Nominal Wall Thickness 0.250 Inch (6.35 mm) and Over Spe
33、cimens, nominally 5 inches (127 mm) long, shall be rough machined to 4 equal circumferential steps, T, 3/4T, 1/2T, and 1/4T, allowing 0.100 inch (2.54 mm) on the diameter for stock removal. Allowance of 0.010 inch (0.25 mm) on the radii for finish machining shall be made. T = nominal wall thickness
34、minus the machining allowance. 3.1.3.6.2 Nominal Wall Thickness Under 0.250 Inch (6.35 mm) Specimens, nominally 5 inches (127 mm) long, after heat treatment as in 3.1.5, shall have 10% of the wall thickness or 0.015 inch (3.81 mm), whichever is less, removed from the outer diameter and be tested as
35、a straight cylinder. 3.1.4 Machining 3.1.4.1 Product Other Than Flat Bars, Slabs, and Plates Over 8 Inches (203 mm) Thick, and Tubing The converted sample shall be machined to conform to the allowance of Table 3 for surface removal, allowing 0.010 inch (0.25 mm) per side for finish machining after h
36、eat treatment. SAE INTERNATIONAL AMS2304B Page 4 of 11_ TABLE 3 - STOCK REMOVAL Nominal Diameter or Distance Between Parallel Sides Inches (Millimeters) Minimum Stock Removal Inch (Millimeters) per Side 0.250 to 0.500 (6.35 to 12.70), incl 0.030 (0.76) Over 0.500 to 0.750 (12.70 to 19.01), incl 0.04
37、5 (1.14) Over 0.750 to 1.000 (19.01 to 25.40), incl 0.060 (1.52) Over 1.000 to 1.500 (25.40 to 38.10), incl 0.075 (1.91) Over 1.500 to 2.000 (38.10 to 50.80), incl 0.090 (2.29) Over 2.000 to 2.500 (50.80 to 63.50), incl 0.125 (3.18) Over 2.500 to 3.500 (63.50 to 88.90), incl 0.156 (3.96) Over 3.500
38、to 4.500 (88.90 to 114.30), incl 0.187 (4.75) Over 4.500 to 6.000 (114.30 to 152.40), incl 0.250 (6.35) 3.1.5 Heat Treatment Rough machined specimens shall, if necessary, be heat treated by suitably austenitizing, quenching, and tempering or by solution and precipitation heat treating to produce har
39、dness of 248 to 352 HB or appropriate lower hardness for steel of low hardenability. Hardness testing shall be in accordance with ASTM E10. Specimens shall be austenitized in a neutral or slightly reducing atmosphere. Following heat treatment, surface scale may be removed by grit blasting or other a
40、cceptable method. 3.1.6 Finish Machining The heat treated specimens shall be finish machined to surface roughness not greater than 32 microinches AA, determined in accordance with ANSI B46.1. The ends of the specimen shall be finished to provide good electrical contact. 3.2 Inspection Magnetic parti
41、cle testing shall be performed in accordance with ASTM E 1444 by the circular, wet, continuous method (See 8.3) using 800 to 1200 amperes per inch (32 to 48 amperes/mm) of diameter or another magnetic particle procedure acceptable to purchaser. If a stepdown bar is used, the smallest step shall be m
42、agnetized and inspected first; the larger steps shall be magnetized and inspected individually in succession of increasing size until all steps have been evaluated. If a longitudinal slice from slab or plate, as in 3.1.3.5, is used, only the longitudinal surfaces perpendicular to the two faces of th
43、e slab or plate shall be inspected. 3.2.1 Cleanliness standards presented herein govern nonmetallic inclusions only (See 8.3). Steel that, during inspection, reveals indications representing actual ruptures, such as cracks, seams, laminations, and laps, will be subject to rejection except where thes
44、e defects result from sample preparation. If such indications are the consequence of sample preparation, a replacement retest sample may be obtained from material adjacent to the original test location. 3.2.2 The results of the magnetic particle testing shall be appropriately recorded. All recorded
45、results shall be identified, filed, and made available to purchaser upon request. SAE INTERNATIONAL AMS2304B Page 5 of 11_ 3.3 Evaluation of Steel Cleanliness After inspection, each indication 1/64 inch (0.4 mm) and over shall be recorded on an inspection chart. All recorded results shall be identif
46、ied, filled, and, upon request, made available to purchaser. Records shall be available for at least three years after shipment of the product. The frequency rating (F) number and the severity rating (S) length of the indications shall be calculated as follows: 3.3.1 Frequency (F) 3.3.1.1 The number
47、 of indications per test specimen is totaled. 3.3.1.2 The frequency per specimen is determined by dividing the total number of indications for each specimen by the test surface area of the specimen frequency in square inches(by dividing 6.45 times the total number of indications for each specimen by
48、 the test surface area of the specimen in square centimeters) 3.3.1.3 The frequency ratings for all test specimens from a heat are totaled. 3.3.1.4 The average frequency rating (F) equals the total frequency rating for all test specimens from a heat divided by the number of test specimens. 3.3.2 Severity
