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 2012 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/AMS4418H AEROSPACE MATERIAL SPECIFICATION AMS4418 REV. H Issued 1961-07 Revised 2
5、012-06 Superseding AMS4418G Magnesium Alloy, Sand Castings 2.5Ag - 2.1Di - 0.70Zr (QE22A-T6) Solution and Precipitation Heat Treated (Composition similar to UNS M18220) RATIONALE AMS4418H revises Composition (3.1), Heat Treatment (3.5) and Sampling for Chemical Analysis (4.3.1), corrects an error in
6、 temperature and time tolerances (3.6.1.2), corrects an error in tolerances for pour temperature (4.4.2.1) and results from a Five Year Review and update of this specification. 1. SCOPE 1.1 Form This specification covers a magnesium alloy in the form of sand castings. 1.2 Application These castings
7、have been used typically for parts requiring high yield strength up to 400 F (204 C), but usage is not limited to such applications. 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 her
8、ein. 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 SAE Publications Available from
9、SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org. AMS2360 Room Temperature Tensile Properties of Castings AMS2361 Elevated Temperature Tensile Properties of Castings AMS2475 Protective Treatment
10、s, Magnesium Alloys SAE AMS4418H Page 2 of 8 AMS2694 In-Process Welding of Castings AMS2804 Identification, Castings AMS2768 Heat Treatment of Magnesium Alloy Castings 2.2 ASTM Publications Available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel
11、: 610-832-9585, www.astm.org. ASTM B 557 Tension Testing Wrought and Cast Aluminum- and Magnesium-Alloy Products ASTM B 557M Tension Testing Wrought and Cast Aluminum- and Magnesium-Alloy Products (Metric) ASTM B 660 Packaging/Packing of Aluminum and Magnesium Products ASTM B 953 Sampling Magnesium
12、and Magnesium Alloys for Spectrochemical Analysis ASTM B 954 Analysis of Magnesium and Magnesium Alloys by Atomic Emission Spectrometry ASTM E 21 Elevated Temperature Tension Tests of Metallic Materials ASTM E 155 Reference Radiographs for Inspection of Aluminum and Magnesium Castings ASTM E 1417 Li
13、quid Penetrant Testing ASTM E 1742 Radiographic Examination 3. TECHNICAL REQUIREMENTS 3.1 Composition Shall conform to the percentages by weight shown in Table 1, determined by spectrochemical methods in accordance with ASTM B 954, or by other analytical methods acceptable to purchaser. TABLE 1 - CO
14、MPOSITION Element min max Silver Didymium (Total Rare Earths) (3.1.1) Zirconium, total Copper Nickel Other Elements, total Magnesium 2.0 1.75 0.40 - - - remainder 3.0 2.5 1.0 0.10 0.01 0.30 3.1.1 Didymium consists of neodymium (not less than 70% of the total) plus praseodymium, along with lesser amo
15、unts of other rare earth elements. Vendor shall analyze and report neodymium and praesodymium in order to determine composition for routine acceptance. When analyzed, the total of all rare earth elements shall not exceed 2.5%. 3.2 Condition Solution and precipitation heat treated to the T6 temper. S
16、AE AMS4418H Page 3 of 8 3.3 Casting Castings shall be produced from metal conforming to 3.1. Furnace or ladle additions of grain-refining elements or alloys shall be added to the melt. Molten metal taken from alloying furnaces, with or without additions of foundry operating scrap (gates, sprues, ris
17、ers, and rejected castings), shall not be poured into castings unless first converted to ingot, analyzed, and remelted or unless the composition of a sample taken after the last addition to the melt conforms to 3.1. 3.3.1 A melt shall be the metal withdrawn from a batch-furnace charge of 2000 pounds
18、 (907 kg) or less as melted for pouring castings or, when permitted by purchaser, a melt shall be 4000 pounds (1814 kg) or less of metal withdrawn from one continuous furnace in not more than eight consecutive hours. 3.3.2 A lot shall be all castings poured from a single melt in not more than eight
19、consecutive hours and solution and precipitation heat treated in the same heat treatment batch. 3.4 Cast Test Specimens Chemical analysis specimens and tensile specimens shall be cast as follows: 3.4.1 Chemical Analysis Specimens Shall be cast from each melt and shall be of any suitable size, shape,
20、 and form. 3.4.2 Tensile Specimens Shall be cast with each lot of castings, shall be of standard proportions conforming to ASTM B 557 or ASTM B 557M with 0.500 inch (12.70 mm) diameter at the reduced parallel gage section, and shall be cast to size in molds made of the regular foundry mix of sand wi
21、thout using chills. Metal for the specimens shall be part of the melt which is used for the castings and shall be subjected to the same grain-refining or alloying treatment given the alloy for the castings. The temperature of the metal during pouring of the specimens shall be not lower than that dur
22、ing pouring of the castings. 3.5 Heat Treatment Castings and representative tensile specimens shall be solution and precipitation heat treated in accordance with AMS2768. At least one set of tensile specimens shall, during each stage of heat treatment, be placed into a batch-type furnace with each l
23、oad of castings or into a continuous furnace at intervals of not longer than 3 hours. 3.6 Properties Castings and representative separately-cast tensile specimens produced in accordance with 3.4.2 shall conform to the following requirements: 3.6.1 Tensile Properties Conformance to the requirements o
24、f 3.6.1.1.1 shall be used as basis for acceptance of castings except when purchaser specifies that the requirements of 3.6.1.1.2 apply: 3.6.1.1 At Room Temperature Shall be as follows, determined in accordance with ASTM B 557 or ASTM B 557M: 3.6.1.1.1 Separately-Cast Specimens Shall meet the require
25、ments shown in Table 2. SAE AMS4418H Page 4 of 8 TABLE 2 - MINIMUM TENSILE PROPERTIES Property Value Tensile Strength Yield Strength at 0.2% Offset Elongation in 4D 35.0 ksi (241 MPa) 25.0 ksi (172 MPa) 2% 3.6.1.1.2 Specimens Cut from Castings or Integrally-Cast Coupons Specimens as in 4.3.4 shall m
26、eet the requirements shown in Table 3: TABLE 3 - MINIMUM TENSILE PROPERTIES Property Value Tensile Strength Yield Strength at 0.2% Offset Elongation in 4D 32.0 ksi (221 MPa) 23.0 ksi (159 MPa) 2% 3.6.1.2 At 400 F (204 C) Shall be as shown in Tables 4 and 5, determined in accordance with ASTM E 21 on
27、 specimens heated to 400 F 5 (204 C 3), held at heat for 10 minutes 1 before testing, and tested at 400 F 5 (204 C 3): 3.6.1.2.1 Separately-Cast Specimens TABLE 4 - MINIMUM TENSILE PROPERTIES Property Value Tensile Strength Yield Strength at 0.2% Offset 25.0 ksi (172 MPa) 19.0 ksi (131 MPa) 3.6.1.2.
28、2 Specimens Cut from Castings or From Integrally-Cast Coupons TABLE 5 - MINIMUM TENSILE PROPERTIES Property Value Tensile Strength Yield Strength at 0.2% Offset 24.0 ksi (165 MPa) 18.0 ksi (124 MPa) 3.6.1.3 When properties other than those specified in 3.6.1.1.2 and 3.6.1.2.2 are required, tensile s
29、pecimens as in 4.3.4, machined from locations indicated on the drawing, from a casting or castings chosen at random to represent the lot shall have the properties indicated on the drawing for such specimens. Property requirements for such specimens may be designated in accordance with AMS2360, AMS23
30、61, or both. 3.7 Quality 3.7.1 Castings, as received by purchaser, shall be uniform in quality and condition, sound, and free from foreign materials and from imperfections detrimental to usage of the castings. 3.7.1.1 Castings shall have smooth surfaces and shall be sufficiently cleaned to permit fl
31、uorescent penetrant inspection. 3.7.1.2 Castings cleaned by blasting shall be pickled in a sulfuric or sulfuric-nitric acid solution to remove not less than 0.002 inch (0.05 mm) of metal before protective treatment as in 5.2.1. SAE AMS4418H Page 5 of 8 3.7.2 Castings shall be produced under radiogra
32、phic control. This control shall consist of radiographic examination of castings in accordance with ASTM E 1742 or other radiographic procedure acceptable to purchaser, until proper foundry technique, which will produce castings free from harmful internal imperfections, is established for each part
33、number and of production castings as necessary to ensure maintenance of satisfactory quality. 3.7.3 When specified, castings shall be subjected to fluorescent penetrant inspection in accordance with ASTM E 1417. 3.7.4 Radiographic, fluorescent penetrant, and other quality standards shall be as agree
34、d upon by purchaser and vendor. ASTM E 155 may be used to define radiographic standards. 3.7.5 Castings shall not be repaired by peening, plugging, welding, or other methods without written permission from purchaser. 3.7.5.1 When permitted in writing by purchaser, defects in castings may be removed
35、and the castings repaired by welding in accordance with AMS2694. 3.7.6 Castings shall not be impregnated, chemically treated, or coated to prevent leakage unless specified or allowed by written permission of purchaser, designating the method to be used. 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibi
36、lity for Inspection The vendor of castings shall supply all samples for vendors tests and shall be responsible for the performance of all required tests. Purchaser reserves the right to sample and to perform any confirmatory testing deemed necessary to ensure that the castings conform to the specifi
37、ed requirements. 4.2 Classification of Tests 4.2.1 Acceptance Tests Composition (3.1), tensile properties at room temperature (3.6.1.1), and quality (3.7) are acceptance tests and shall be performed to represent each lot or melt as applicable. 4.2.1.1 Tensile properties of specimens cut from casting
38、s or from integrally-cast coupons shall be determined only when specified by purchaser or when separately-cast specimens are not available. Tensile properties of separately-cast specimens need not be determined when tensile properties of specimens cut from castings or from integrally-cast coupons ar
39、e determined. 4.2.2 Periodic Tests Tensile properties at 400 F (204 C) are periodic tests and shall be performed at a frequency selected by the vendor unless frequency of testing is specified by purchaser. 4.2.3 Preproduction Tests All technical requirements are preproduction tests and shall be perf
40、ormed prior to or on the first-article shipment of a casting to a purchaser, when a change in material and/or processing requires reapproval as in 4.4.2, and when purchaser deems confirmatory testing to be required. 4.3 Sampling and Testing Shall be in accordance with the following: SAE AMS4418H Pag
41、e 6 of 8 4.3.1 One chemical analysis specimen in accordance with 3.4.1 and ASTM B 953 from each melt or a casting from each lot. 4.3.2 One separately-cast tensile specimen in accordance with 3.4.2 from each lot except when purchaser requires properties of specimens cut from castings or from integral
42、ly-cast coupons. 4.3.3 Sufficient castings of each part number in accordance with 4.4.1 to satisfy dimensional, property, and quality evaluations. 4.3.4 One or more castings from each lot when tensile properties are required from specimens machined from castings. Specimens shall conform to ASTM B 55
43、7 or ASTM B 557M and shall be either 0.500 inch (12.70 mm) diameter at the reduced parallel gage section, subsize specimens proportional to the standard, or standard sheet-type specimens. For determining conformance to the requirements of 3.6.1.3, if specimen locations are not shown on the drawing,
44、not less than four tensile specimens, two from the thickest section and two from the thinnest section, shall be cut from a casting or castings from each lot. 4.3.4.1 When permitted by purchaser, tensile specimens conforming to ASTM B 557 or ASTM B 557M excised from integrally-cast coupons may be use
45、d in lieu of separately-cast specimens (4.3.2) or specimens cut from a casting or castings (4.3.4). Size, number, and location of integrally-cast coupons shall be as specified by purchaser. 4.4 Approval 4.4.1 Sample castings from new or reworked patterns and the casting procedure shall be approved b
46、y purchaser before castings for production use are supplied, unless such approval be waived by purchaser. 4.4.2 Vendor shall establish, for production of sample castings of each part number, parameters for the process control factors that will produce acceptable castings; these shall constitute the
47、approved casting procedure and shall be used for producing production castings. If necessary to make any change in parameters for the process control factors, vendor shall submit for reapproval a statement of the proposed changes in processing and, when requested, test specimens, sample castings, or
48、 both. Production castings incorporating the revised operations shall not be shipped prior to receipt of reapproval. 4.4.2.1 Process control factors for producing castings include, but are not limited to, the following: Type of furnace Furnace atmosphere Ladle addition or grain refining practice San
49、d formulation Fluxing or oxide removal procedure Gating and risering practices Metal pouring temperature; variation of 50 F (28 C) is permissible Solidification and cooling procedures Solution and precipitation heat treatment cycles Cleaning operations Methods of inspection 4.4.2.1.1 Any of the above process control factors for which parameters are considered proprietary by the vendor may be assigned a code designati
