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/AMS4429A AEROSPACE MATERIAL SPECIFICATION AMS4429 REV. A Issued 2004-12 Revised 2012-05 Super
5、seding AMS4429 Magnesium Alloy Castings, Sand 2.8Nd - 1.4Gd - 0.4Zn - 0.6Zr (EV31A - T6) Solution and Precipitation Heat Treated (Composition similar to UNS M12310) RATIONALE AMS4429A revises Composition (3.1), Sampling for Chemical Analysis (4.3.1), and is a Five Year Review and Update of this spec
6、ification. 1. SCOPE 1.1 Form This specification covers a magnesium alloy in the form of sand castings. 1.2 Application These castings have been used typically for parts requiring a combination of light weight, high yield strength up to 400 F (204 C), and relatively high corrosion resistance, but usa
7、ge 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 herein. The supplier may work to a subsequent revision of a document unless a specific document
8、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: 877-606-7323 (insi
9、de USA and Canada) or 724-776-4970 (outside USA), www.sae.org. AMS2360 Room Temperature Tensile Properties of Castings AMS2475 Protective Treatments, Magnesium Alloys AMS2694 In-Process Welding of Castings AMS2750 Pyrometry AMS2804 Identification, Castings SAE AMS4429A Page 2 of 8 2.2 ASTM Publicati
10、ons 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 B 117 Standard Practice for Operating Salt Spray (Fog) Apparatus ASTM B 557 Tension Testing Wrought and Cast Aluminum- and Magnesium- Alloy Products AS
11、TM B 557M Tension Testing Wrought and Cast Aluminum- and Magnesium- Alloy Products (Metric) ASTM B 953 Sampling Magnesium and Magnesium Alloys for Spectrochemical Analysis ASTM B 954 Analysis of Magnesium and Magnesium Alloys by Atomic Emission Spectrometry ASTM B 660 Packaging/Packing of Aluminum a
12、nd Magnesium Products ASTM E 155 Reference Radiographs for Inspection of Aluminum and Magnesium Castings ASTM E 1417 Liquid 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 by s
13、pectrochemical methods in accordance with ASTM B 954, or by other analytical methods acceptable to purchaser. TABLE 1- COMPOSITION Element min max Neodymium 2.6 3.1 Gadolinium 1.0 1.7 Zinc 0.20 0.50 Zirconium 0.4 1.0 Other Rare Earths (3.1.1) - 0.4 Silver - 0.05 Copper - 0.01 Iron - 0.010 Nickel - 0
14、.0020 Other Elements, each (3.1.2) - 0.01 Magnesium remainder 3.1.1 Other rare earths shall principally be the total of cerium, lanthanum, and praseodymium. The supplier shall analyze for the presence of these three elements when determining acceptance but the presence of additional rare earth eleme
15、nts shall not be cause for rejection provided the total remains less than 0.4%. 3.1.2 Determination not required for routine acceptance. 3.2 Condition Solution and precipitation heat treated to the T6 temper. SAE AMS4429A Page 3 of 8 3.3 Casting Castings shall be produced from metal conforming to 3.
16、1. Metal remelted from previously analyzed ingot may be poured directly into castings. 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, risers, a
17、nd 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 (907
18、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 consec
19、utive hours and solution and precipitation heat treated in the same heat treat 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, or form.
20、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 with the regular foundry mix of sand without usi
21、ng 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 metal for the castings. The temperature of the metal during pouring of the specimens shall be not lower than that during pouri
22、ng of the castings. 3.4.3 Integrally-Cast Coupons for Corrosion Specimens When salt spray (fog) corrosion properties are to be determined using integrally-cast coupons (See 3.6.2), specimens shall be approximately 3 inches (75 mm) square by 0.25 inch (6.0 mm) thick. One or more integrally-cast coupo
23、ns should remain on castings where possible until just prior to protective treatment specified in 5.2. If it is necessary to remove integrally-cast coupons prior to protective treatments (pickle), coupons shall accompany castings through any further processing such as, but not limited to, heat treat
24、ment, blasting, and etching. 3.5 Heat Treatment Castings and representative tensile specimens shall be heated to the proper temperature, not exceeding 980 F (527 C), held at heat for the proper time for solution treatment, quenched as required, and reheated to a temperature between 390 to 410 F (199
25、 to 210 C) and held at heat for the proper time for precipitation heat treatment to meet the requirements of 3.6. At least one set of tensile specimens shall, during each stage of heat treatment, be put into a batch type furnace with each load of castings or into a continuous furnace at intervals of
26、 not longer than 3 hours. Pyrometry shall be in accordance with AMS2750. 3.6 Properties Castings and representative separately-cast tensile specimens produced in accordance with 3.4.2 shall conform to the following requirements: SAE AMS4429A Page 4 of 8 3.6.1 Tensile Properties Conformance to the re
27、quirements of 3.6.1.1.1 shall be used as the 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 shown in 3.6.1.1.1 or 3.6.1.1.2 determined in accordance with ASTM B 557 or ASTM B 557M: 3.6.1.1.1 Separatel
28、y Cast Specimens Shall meet the requirements of Table 2. TABLE 2 - MINIMUM TENSILE PROPERTIES Property Value Tensile Strength, minimum 36.0 ksi (248 MPa) Yield Strength at 0.2% Offset, minimum 21.0 ksi (145 MPa) Elongation in 4D, minimum 2.0% 3.6.1.1.2 Specimens Cut from Castings and Integrally-Cast
29、 Coupons Specimens as in 4.3.4 shall meet the requirements of Table 3. TABLE 3 - MINIMUM TENSILE PROPERTIES Property Value Tensile Strength, minimum 36.0 ksi (248 MPa) Yield Strength at 0.2% Offset, minimum 21.0 ksi (145 MPa) Elongation in 4D, minimum 2.0% 3.6.1.2 When properties other than those sp
30、ecified in Table 3 are required, tensile specimens as in 4.3.4 taken 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 may be designated in accordance
31、 with AMS2360. 3.6.2 Corrosion Resistance Shall not be greater than 0.090 inch (2.29 mm) per year for integrally-cast specimens or, when specified, specimens cut from castings, determined in accordance with 3.6.2.1. 3.6.2.1 Corrosion rate shall be determined in accordance with ASTM B 117 except that
32、, prior to exposure, specimens shall be accurately weighed to within 0.01 gram (W1). Specimens shall be exposed to the salt spray for not less than 120 hours. Following exposure, specimens shall be rinsed with tap water and cleaned of adherent corrosion product by immersing in a hot 190 F 88 C 20% c
33、hromic acid plus 1% silver nitrate solution for 1 to 2 minutes. Cleaned specimens shall be rinsed in hot water, dried in a stream of hot air, and reweighed (W2). The measured weight loss (WL) shall be calculated (W1 - W2) and used for calculating corrosion rate, using the following equations: (Eq. 1
34、) SAE AMS4429A Page 5 of 8 where: WL = Measured weight loss in mg SA = Total surface area of specimen in cm2EP = Exposure time in days D = Density, 1.82 gram/cm3mcd = mg/cm2per day 3.7 Quality 3.7.1 Castings, as received by purchaser, shall be uniform in quality and condition, sound, and free from f
35、oreign 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 fluorescent penetrant inspection. 3.7.1.2 Castings cleaned by blasting shall be etched in a sulfuric or sulfuric-nitric acid solution
36、to remove not less than 0.002 inch (0.05 mm) of metal before protective treatment as in 5.2. 3.7.2 Castings shall be produced under radiographic control. This control shall consist of radiographic examination of castings in accordance with ASTM E 1742, or other radiographic procedures acceptable to
37、purchaser, until proper foundry technique, which will produce castings free from harmful internal imperfections, is established for each part number and of production castings as necessary to ensure maintenance of satisfactory quality. 3.7.3 When specified, castings shall be subjected to fluorescent
38、 penetrant inspection in accordance with ASTM E 1417. 3.7.4 Radiographic, fluorescent penetrant, and other quality standards shall be as agreed upon by purchaser and vendor. ASTM E 155 may be used to define radiographic acceptance standards. 3.7.5 Castings shall not be reworked by peening, plugging,
39、 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 and the castings reworked by welding in accordance with AMS2694. When authorized, rework welding shall be done before heat treatment. 3.7.6 Casting
40、s 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 Responsibility for Inspection The vendor of castings shall supply all samples for vendor
41、s 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 product conforms to specified requirements. 4.2 Classification of Tests 4.2.1 Acceptance Tests Except as spec
42、ified in 4.2.1.1, 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 melt or lot as applicable. SAE AMS4429A Page 6 of 8 4.2.2 Periodic Tests Corrosion resistance (3.6.3) is a periodic test and shall be
43、 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 classified as preproduction tests and shall be performed prior to or on the first-article shipment of a casting to a purchaser, when a chan
44、ge 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: 4.3.1 One chemical analysis specimen from each melt for conformance to ASTM B 953 and 3.1. 4.3.2 One sep
45、arately-cast tensile specimen in accordance with 3.4.2 from each lot except when purchaser requires properties of specimens cut from castings or from integrally-cast coupons. Tensile properties of separately-cast specimens need not be determined when tensile properties of specimens cut from castings
46、 or from integrally-cast coupons are determined. 4.3.3 Two preproduction castings in accordance with 4.4.1 of each part number. 4.3.4 Except as permitted by 4.3.4.1, one or more castings from each lot when tensile properties are required from specimens cut from castings. Specimens shall conform to A
47、STM B 557 or ASTM B 557M and shall be either 0.500 inch (12.7 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 3.6.1.2, if specimen locations are not shown on the dr
48、awing, 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. 4.3.5 Two integrally-cast coupons for corrosion resistance testing when required. Location of such coupons shall be as agreed upon by p
49、urchaser and vendor. 4.3.5.1 When permitted by purchaser, tensile specimens conforming to ASTM B 557 or ASTM B 557M excised from integrally-cast coupons may be used 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
