1、Designation: A439/A439M 15Standard Specification forAustenitic Ductile Iron Castings1This standard is issued under the fixed designation A439/A439M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last revision. A numbe
2、r in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 This specification covers austenitic ductile iron cast
3、ings,which are used primarily for their resistance to heat, corrosion,and wear, and for other special purposes.1.2 Austenitic ductile iron, also known as austenitic nodulariron or austenitic spheroidal iron, is characterized by having itsgraphite substantially in a spheroidal form and substantiallyf
4、ree of flake graphite. It contains some carbides and sufficientalloy content to produce an austenitic structure.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem s
5、hall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.2. Referenced Documents2.1 ASTM Standards:2A247 Test Method for Evaluating the Microstructure ofGraphite in Iron CastingsA370 Test Methods and Definitions for Mechanical Testi
6、ngof Steel ProductsE8 Test Methods for Tension Testing of Metallic MaterialsE10 Test Method for Brinell Hardness of Metallic MaterialsE30 Methods for Chemical Analysis of Ferroalloys3E59 Practice for Sampling Steel and Iron for Determinationof Chemical Composition3E351 Test Methods for Chemical Anal
7、ysis of Cast IronAllTypes3. Ordering Information3.1 Orders for material to this specification shall include thefollowing information:3.1.1 ASTM designation,3.1.2 Type of austenitic ductile iron required (see 6.1),3.1.3 Heat treatment options (see 4.3 4.6),3.1.4 If repair of castings is permitted (se
8、e 4.7),3.1.5 Size and number of test bars required (see 9.1 9.4and 10.1),3.1.6 Special tests, if required (see 12.1),3.1.7 Certification, if required (see 14.1), and3.1.8 Different preparation for delivery requirements, ifneeded (see 15.1).4. Manufacture4.1 Melting may be done in any furnaces that p
9、roducecastings meeting the chemical and mechanical requirementsoutlined in this specification. These include cupolas, airfurnaces, electric furnaces, crucible furnaces, and so forth.Nodularizing and inoculation practice shall be optional withthe foundry to produce a microstructure in accordance with
10、 1.2and Test Method A247.4.2 Austenitic ductile iron castings may be supplied ineither the as-cast or the heat-treated condition.4.3 By agreement between the manufacturer and thepurchaser, the castings may be stress relieved by heating to1150 to 1200F 620 to 650C for not less than 1 h and not formor
11、e than 2 h per inch 25 mm of thickness in the thickestsection. Heating and cooling shall be uniform and shall not bemore than 400F/h 220C/h for castings less than 1 inch25 mm in maximum thickness and shall be not more than400F/h 220C/h divided by the maximum section thicknessin inches 25 mm for thic
12、ker castings. During the coolingcycle, castings may be cooled in still air after the temperaturehas dropped to 600F 310C.4.4 By agreement between the manufacturer and thepurchaser, the castings may be in-mold stress relieved byallowing castings to cool slowly in the mold at a rate notexceeding 400F/
13、h 220C/h. Once the temperature hasdropped below 600F 310C, castings can be removed fromthe mold and cooled in still air.1This specification is under the jurisdiction of ASTM Committee A04 on IronCastings and is the direct responsibility of Subcommittee A04.02 on Malleable andDuctile Iron Castings.Cu
14、rrent edition approved Nov. 1, 2015. Published December 2015. Originallyapproved in 1960. Last previous edition approved in 2009 as A439 83 (2009).DOI: 10.1520/A0439_A0439M-15.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. Fo
15、r Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19
16、428-2959. United States14.5 Whenever dimensional changes in high-temperatureservice are a problem, by agreement between the manufacturerand the purchaser, the castings may be stabilized by heating at1600F 870C for a period of 1 h per inch 25 mm of section,with a minimum period of 1 hour, followed by
17、 uniformcooling, preferably in still air. Otherwise, the austenite, whichis super-saturated with respect to carbon, can reject carbonduring service and produce dimensional changes.4.6 By agreement between the manufacturer and thepurchaser, castings with chilled edges or excessive carbidesmay be anne
18、aled at 1750 to 1900F 960 to 1040C for 0.5 hto 5 h followed by uniform cooling, preferably in still air.4.7 Repair by welding, plugging, or other approved methodsmay be done only with written permission from the purchaser.5. Magnetic Properties5.1 In the event that nonmagnetic castings are specified
19、, themagnetic permeability test shall be used. The maximummagnetic permeability value shall be agreed upon between themanufacturer and the purchaser.NOTE 1A convenient shop test for differentiating the various types ofaustenitic ductile iron is based on the fact that a ground face of either thetest
20、bar or the castings of Types D-2 and D-2C does not attract a smallsteel horseshoe-type magnet which is normally attracted to steel (Alnicomagnet should not be used.). Types D-3, D-3A, D-5, and D-5B areattracted, and types D-2B, D-2S, D-4, and D-5S are slightly attracted. Thisnonmagnetic test is a co
21、nvenient qualitative test only for Types D-2 andD-2C and shall not be used as a basis for acceptance.6. Chemical Requirements6.1 Many combinations of alloys can be used to obtain anaustenitic ductile iron. This specification includes ten generaltypes defined by the composition limits in Table 1.6.2
22、Samples taken from test coupons, broken testspecimens, or castings shall conform to the requirements as tochemical composition prescribed in Table 1. Sampling shall beconducted in accordance with Practice E59 and chemicalanalyses in accordance with Test Methods E351 and E30. TestMethods E30 should o
23、nly be used for analyzing those elementsfor which specific coverage is not provided for in Test MethodsE351.6.3 Spectrometric techniques may also be used for analysis,but should a dispute arise concerning chemical composition,Test Methods E351 and E30 shall be used for referee methods.6.4 The chemic
24、al analysis for total carbon shall be made oneither chilled cast pencil-type specimens or thin wafers ap-proximately132 in. 1.0 mm thick cut from test coupons.Drillings shall not be used because of attendant loss ofgraphite.7. Mechanical Requirements7.1 Test specimens of austenitic ductile iron made
25、 accordingto this specification shall meet the test requirements prescribedin Table 2.7.2 The yield strength shall be determined in accordancewith Test Methods E8, using one of the following procedures:the 0.2 % off-set method or the extension under load methodmay be used, by agreement between the p
26、urchaser and themanufacturer.7.3 Brinell hardness shall be determined as HBW 10/3000in accordance with Test Method E10.8. Workmanship, Finish, and Appearance8.1 The castings shall conform substantially to the dimen-sions on the drawings furnished by the purchaser, or if nodrawing has been provided,
27、to the dimensions predicated bythe pattern supplied by the purchaser. The castings shall be freeof injurious defects. Surfaces of the castings shall be free ofburnt-on sand and shall be reasonably smooth. Runners, risers,fins, and other cast-on pieces shall be removed. In otherrespects, the castings
28、 shall conform to whatever points arespecifically agreed upon between the manufacturer and thepurchaser.9. Test Bars9.1 The standard test bars shall be the 1-in. 25-mm “Y”block and 1-in. 25-mm keel block as shown in Figs. 1 and 2,respectively. A modified keel block cast from the mold shownin Fig. 3
29、may be substituted for the 1-in. 25-mm “Y” block orthe 1-in. 25-mm Keel block.9.2 Whenever the section size of the castings is consider-ably less or greater than 1 in. 25 mm and by agreementbetween the purchaser and the manufacturer, the12-in. 13-mm or 3-in. 75-mm “Y” blocks shown in Fig. 1 may beus
30、ed.9.3 The test bars shall be cast in open molds made of asuitable core sand with a minimum of 112 in. 38 mm of sandTABLE 1 Chemical RequirementsElementTypeD-2AD-2B D-2C D-2S D-3AD-3A D-4 D-5 D-5B D-5SComposition, %Total carbon,max3.00 3.00 2.90 2.6 2.60 2.60 2.60 2.40 2.40 2.30Silicon 1.503.00 1.50
31、3.00 1.003.00 4.805.80 1.002.80 1.002.80 5.006.00 1.002.80 1.002.80 4.905.50Manganese 0.701.25 0.701.25 1.802.40 1.00 max 1.00 maxB1.00 maxB1.00 maxB1.00 maxB1.00 maxB1.00 maxPhosphorus,max0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08Nickel 18.0022.00 18.0022.00 21.0024.00 24.0028.00 28.0032.00
32、28.0032.00 28.0032.00 34.0036.00 34.0036.00 34.0037.00Chromium 1.752.75 2.754.00 0.50 maxB1.752.25 2.503.50 1.001.50 4.505.50 0.10 max 2.003.00 1.752.25AAdditions of 0.7 to 1.0 % of molybdenum can increase the mechanical properties above 800F (425C).BNot intentionally added.A439/A439M 152TABLE 2 Mec
33、hanical RequirementsInch-Pound GradesElementTypeD-2 D-2B D-2C D-2S D-3 D-3A D-4 D-5 D-5B D-5SPropertiesTensile strength, min, ksi 58 58 58 55 55 55 60 55 55 55Yield strength (0.2 % offset), min, ksi 30 30 28 30 30 30 . . . 30 30 30Elongation in 2 in., min, % 8.0 7.0 20.0 10.0 6.0 10.0 . . . 20.0 6.0
34、 10.0Brinell hardness (3000 kg) 139202 148211 121171 131193 139202 131193 202273 131185 139193 131193Metric GradeElementTypeD-2 D-2B D-2C D-2S D-3 D-3A D-4 D-5 D-5B D-5SPropertiesTensile strength, min, MPa 400 400 400 380 380 380 415 380 380 380Yield strength (0.2 % offset), min, MPa 210 210 195 210
35、 210 210 . . . 210 210 210Elongation in 50 mm, min, % 8.0 7.0 20.0 10.0 6.0 10.0 . . . 20.0 6.0 10.0Brinell hardness (3000 kg) 139202 148211 121171 131193 139202 131193 202273 131185 139193 131193Dimensions“Y” Block SizeFor Castings of Thickness Lessthan12 in. 13 mmFor Castings of Thickness12 in.13
36、mm to 112 in. 38 mmFor Castings of Thickness 112 in.38 mm and Overin. mm in. mm in. mmA12 13 1 25 3 75B158 40 218 54 5 125C 2 50 3 75 4 100D 4 100 6 150 8 200E 7 175 7 175 7 175approx approx approx approx approx approxF916 15 1116 28 3116 80G718 180 718 180 718 180approx approx approx approx approx
37、approxFIG. 1 “Y” Blocks for Test CouponsA439/A439M 153on all sides and bottom of the12 and 1-in. 13 and 25-mm testbars and 3 in. 75 mm of sand for the 3-in. 75-mm test bar.9.4 When investment castings are made to this specification,the manufacturer may use test specimens cast to size incorpo-rated i
38、n the mold with the castings, or separately cast to sizeusing the same type of mold and the same thermal conditionsthat are used to produce the castings. These test specimensshall be made to the dimensions shown in Fig. 3 and Fig. 4 ofTest Methods and Definitions A370.9.5 It is recommended that test
39、 bars be poured immediatelyafter the castings and from the same ladle of metal. Test barsshall be left in the mold until they have cooled to a blackappearance. If castings are to be heat treated, test bars shall beincluded in the same furnace load.10. Number of Tests10.1 Test bars shall be poured fr
40、om each ladle treated withnodularizing agent, unless otherwise specified.10.2 The number of test bars cast shall be agreed upon bythe manufacturer and the purchaser.10.3 One tension test shall be made from sections cut fromthe test bars as shown in Fig. 4. If any tension test showsobvious foundry or
41、 machining defects, another specimen shallbe cut from the same test bar or from another test barrepresenting the same metal. If the retest specimen fails toconform to this specification, the castings they represent shallbe rejected.11. Tension Test Specimens11.1 The standard round tension test speci
42、men with 2-in.50-mm gauge length shown in Fig. 5 shall be used, exceptwhen the12-in. 13-mm “Y” block is used or when specimensare cut from castings under34-in. 20-mm thickness. In thesecases, either of the test specimens shown in Fig. 6 shall besatisfactory.11.2 By agreement between the manufacturer
43、 and thepurchaser, tension test specimens may be cut directly fromcentrifugal or other permanent mold castings. The location andorientation of such tension test specimens cut from castingsshall be specified as agreed upon by the manufacturer and thepurchaser.12. Additional Tests12.1 Hydrostatic test
44、s for pressure castings, radiographystandards, fracture tests, microstructure standards, or any otherspecial tests may be set up by mutual agreement between themanufacturer and the purchaser.13. Responsibility for Inspection13.1 Unless otherwise specified in the contract or purchaseorder, the manufa
45、cturer is responsible for the performance ofall inspection requirements as specified herein. Except asotherwise specified in the contract or order, the manufacturermay use his own or any other facilities suitable for theperformance of the inspection requirements specified herein,unless disapproved b
46、y the purchaser. The purchaser reservesthe right to perform any of the inspections set forth in thespecification where such inspections are deemed necessary toassure supplies and services conform to prescribed require-ments.14. Certification14.1 When agreed upon in writing by the purchaser and thesu
47、pplier, a certification shall be made the basis of acceptance ofthe material. This shall consist of a copy of the manufacturerstest report or a statement by the supplier, accompanied by acopy of the test results that the material has been tested andinspected in accordance with the provisions of this
48、 specifica-tion. Each certification so furnished shall be signed by anauthorized agent of the supplier or manufacturer.15. Packaging and Package Marking15.1 Unless otherwise specified in the contract or purchaseorder, preservation and packaging of casting shall be inaccordance with the manufacturers
49、 commercial practice.Packing and marking shall also be adequate to ensure accep-tance and safe delivery by the carrier for the mode oftransportation employed.16. Keywords16.1 austenitic; corrosion resistant; ductile iron; mechanicalproperties; nodular iron; tensile strength; yield strengthMetric Equivalentsin.12 1112 212mm 13 25 38 63NOTE 1The length of the keel block shall be 6 in. 150 mm.FIG. 2 Keel Block for Test Cou