1、Designation: A 436 84 (Reapproved 2006)Standard Specification forAustenitic Gray Iron Castings1This standard is issued under the fixed designation A 436; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This specification covers austenitic gray iron castin
3、gsthat are used primarily for their resistance to heat, corrosion,and wear. Austenitic gray iron is characterized by uniformlydistributed graphite flakes, some carbides, and the presence ofsufficient alloy content to produce an austenitic structure.1.2 The values stated in inch-pound units are to be
4、 regardedas the standard.2. Referenced Documents2.1 ASTM Standards:2E30 Test Methods for Chemical Analysis of Steel, CastIron, Open-Hearth Iron, and Wrought Iron3E59 Practice for Sampling Steel and Iron for Determinationof Chemical Composition3E94 Guide for Radiographic ExaminationE 165 Test Method
5、for Liquid Penetrant ExaminationE 351 Test Methods for Chemical Analysis of Cast IronAll TypesE 433 Reference Photographs for Liquid Penetrant Inspec-tionE 446 Reference Radiographs for Steel Castings Up to 2 in.51 mm in Thickness3. Ordering Information3.1 Orders for material to this specification s
6、hall include thefollowing information:3.1.1 ASTM designation and date of issue,3.1.2 Type of austenitic gray iron required (see 5.1),3.1.3 Heat treatment required (see 4.2 through 4.5),3.1.4 If repair of castings is permitted (see 4.6),3.1.5 Size and number of test bars required (see 11 through8.4 a
7、nd 12.1),3.1.6 If special tests are required (see Section 7 and 9.1),3.1.7 If certification is required (see 14.1), and3.1.8 If different preparation for delivery requirements areneeded (see 15.1).4. Materials and Manufacture4.1 Melting may be done in any furnace that producescastings meeting the ch
8、emical compositions and mechanicalproperties outlined in this specification. These include cupolas,air furnaces, electric furnaces, crucible furnaces, and so forth.4.2 By agreement between the manufacturer and the pur-chaser, the castings may be stress relieved by heating to andholding in the temper
9、ature range from 1150 to 1200F (620 to650C) for not less than 1 nor more than 2 h/in. of thickness inthe thickest section. Heating and cooling shall be uniform andshall be not more than 400F (222C)/h for castings less than1 in. in maximum thickness, nor more than 400F/h divided bythe maximum section
10、 thickness in inches for thicker castings.During the cooling cycle, castings may be cooled in still airafter the temperature has dropped to 600F (315C).4.3 If the manufacturer can demonstrate that another treat-ment provides satisfactory stress relief, it may be used byagreement between the manufact
11、urer and the purchaser.4.4 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 1 h/in. of section, for a minimum of 1 h.Otherwise, the austenite that is supersatura
12、ted with respect tocarbon may reject carbon during service and produce dimen-sional changes.4.5 By agreement between the manufacturer and the pur-chaser, castings with chilled edges or excessive carbides maybe annealed at 1750 to 1900F (955 to 1040C) for12 to5h,followed by uniform cooling, preferabl
13、y in still air.4.6 Castings shall not be repaired by welding, plugging, orother methods without written permission from the purchaser.1This specification is under the jurisdiction of ASTM Committee A04 on IronCastings and is the direct responsibility of SubcommitteeA04.01 on Grey and WhiteIron Casti
14、ngs.Current edition approved Oct. 1, 2006. Published October 2006. Originallyapproved in 1959. Last previous edition approved in 2001 as A 43684 (2001).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMSta
15、ndards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5. Chemical Composition5.1 Many combinations of alloys can be used to obtain anauste
16、nitic gray iron. This specification includes only the sixtypes defined by the chemical composition limits specified inTable 1.5.2 The chemical analysis for total carbon shall be made onchilled cast pencil-type specimens or from thin wafers approxi-mately132 in. (0.8 mm) thick cut from test coupons.
17、Drillingsare not reliable because of the probable loss of graphite.5.3 Drillings taken from test coupons, broken test speci-mens, or castings shall conform to the requirements forchemical composition as given in Table 1. Sampling shall beconducted in accordance with Practice E59 and chemicalanalysis
18、 in accordance with Test Methods E 351 and TestMethods E30. Test Methods E30 should only be used foranalyzing those elements for which specific coverage is notprovided for in Test Methods E 351.5.4 Spectrometric techniques may also be used for analysis,but should a dispute arise concerning chemical
19、composition,chemical analyses determined by Test Methods E 351 and TestMethods E30shall be used for referee analysis.6. Mechanical Properties6.1 Although these irons are not used primarily for theirstrength, the tensile strength and Brinell hardness are indicativeof the correct metallurgical structu
20、re. The six types shallconform to the requirements given in Table 2.7. Magnetic Property Requirements Magnetic PropertyRequirements7.1 A convenient shop test for differentiating the varioustypes of austenitic gray iron is based on the fact that a groundface of either the test bars or the castings of
21、 Types 1, 2, and 4will not attract a small steel horseshoe-type magnet, that isnormally attracted to steel. Types 1b,2b, 3, and 5 may beattracted to a magnet. This nonmagnetic test is a convenientqualitative test only for Types 1, 2, and 4 and shall not be usedas a basis for acceptance. In the event
22、 that nonmagneticcastings are specified, the magnetic permeability test shall beused. The specific test conditions and magnetic permeabilitylimits shall be agreed upon between the manufacturer and thepurchaser.NOTE 1Alnico magnets should not be used.8. Test Bars8.1 The separately cast test bars from
23、 which tension testspecimens are to be machined shall be cast to the size andshape shown in Fig. 1. The size of bar cast to represent thecasting shall be at the option of the purchaser. In case no optionis expressed, the manufacturer shall make the choice. The testbars shall be cast in open molds ma
24、de of suitable core sandwith a minimum of 112 in. (38 mm) of sand on all sides andbottom of the12-in. (13-mm) and 1-in. (25-mm) sizes, and 3 in.(76 mm) of sand for the 3-in. test bar.8.2 By agreement between the manufacturer and the pur-chaser, the 1-in. (25-mm) keel block shown in Fig. 2 may beused
25、. It shall be an open mold made of suitable core sand witha minimum of 112 in. (38 mm) of sand on all sides and bottom.8.3 It is recommended that test bars be poured immediatelyafter the castings and from the same ladle of metal. If castingsare to be heat treated, test bars shall be included in the
26、samefurnace load.8.4 By agreement between the manufacturer and the pur-chaser, 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 manufacture
27、r and thepurchaser.9. Workmanship, Finish, and Appearance9.1 The castings shall conform substantially to the dimen-sions on the drawings furnished by the purchaser, or if nodrawing has been provided, to the dimensions predicated bythe pattern supplied by the purchaser. The castings shall be freeof i
28、njurious defects. Surfaces of the castings shall be free ofburnt-on sand and shall be reasonably smooth. In otherrespects, the castings shall conform to whatever points may bespecifically agreed upon between the manufacturer and thepurchaser.10. Tension Test Specimens10.1 The round tension test spec
29、imen with 2-in. or 50-mmgage length shown in Fig. 3 shall be used, except when the12-in. (13-mm) “Y” block is used or when specimens are cutfrom castings under34-in. (19.0-mm) thickness. In these cases,either of the test specimens shown in Fig. 4 shall be satisfac-tory.11. Number of Test11.1 The num
30、ber of test bars cast shall be agreed upon bythe manufacturer and the purchaser.11.2 One tension test shall be made from sections cut fromthe test bars as shown in Fig. 5. If any tension test specimenshows obvious defects, another may be cut from the same testbar or from another test bar representin
31、g the same metal.12. Other Tests12.1 Hydrostatic tests for pressure castings, fracture tests,microstructure standards, radiography standards, and liquidpenetrant inspection may be set up by mutual agreementbetween the manufacturer and the purchaser.12.2 Radiography, when required, shall be in accord
32、ancewith Guide E94and Reference Radiographs E 446.12.3 Liquid penetrant inspection, when required, shall be inaccordance with Test Method E 165 and Reference Photo-graphs E 433.13. Responsibility for Inspection13.1 Unless otherwise specified in the contract or purchaseorder, the manufacturer is resp
33、onsible 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 by the purchase
34、r. The purchaser reservesthe right to perform any of the inspections set forth in theA 436 84 (2006)2specification where such inspections are deemed necessary toassure supplies and services conform to the prescribed require-ments.14. Waiving of Inspection by Agreement14.1 When agreed upon in writing
35、 by the purchaser and thesupplier, 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 sampled,tested, and inspected in
36、accordance with the provisions of thespecification specified. Each certification so furnished shall besigned by an authorized agent of the supplier or manufacturer.15. Preparation for Delivery15.1 Unless otherwise specified in the contract or purchaseorder, cleaning, preservation, and packaging of c
37、astings shallbe in accordance with the manufacturers 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; gray iron castings; high-nickelTABLE 1 Chemical RequirementsE
38、lement Composition, %Type 1 Type 1b Type 2 Type 2b Type 3 Type 4 Type 5 Type 6Carbon, total, max 3.00 3.00 3.00 3.00 2.60 2.60 2.40 3.00Silicon 1.002.80 1.002.80 1.002.80 1.002.80 1.002.00 5.006.00 1.002.00 1.502.50Manganese 0.51.5 0.51.5 0.51.5 0.51.5 0.51.5 0.51.5 0.51.5 0.51.5Nickel 13.5017.50 13
39、.5017.50 18.0022.00 18.0022.00 28.0032.00 29.0032.00 34.0036.00 18.0022.00Copper 5.507.50 5.507.50 0.50 max 0.50 max 0.50 max 0.50 max 0.50 max 3.505.50Chromium 1.52.5 2.503.50 1.52.5 3.006.00A2.503.50 4.505.50 0.10 max 1.002.00Sulfur, max 0.12 0.12 0.12 0.12 0.12 0.12 0.12 0.12Molybdenum, max . . .
40、 . . . . 1.00AWhere some machining is required, the 3.004.00 % chromium range is recommended.TABLE 2 Mechanical RequirementsType 1 Type 1b Type 2 Type 2b Type 3 Type 4 Type 5 Type 6Tensile strength, min, ksi (MPa) 25 (172) 30 (207) 25 (172) 30 (207) 25 (172) 25 (172) 20 (138) 25 (172)Brinell hardnes
41、s (3000 kg) 131 183 149 212 118 174 171 248 118 159 149 212 99 124 124 174Dimensions“Y” Block SizeFor Castings of Thickness Lessthan12 in. (13 mm)For Castings of Thickness12 in.(13 mm) to 112 in. (38 mm)For Castings of Thickness of112 in. (38 mm) and Overin. mm in. mm in. mmA12 13 1 25 3 75B158 40 2
42、18 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 approxNOTE116 in. = 1.6 mm;18 in. = 3.2 mm.FIG. 1 “Y” Blocks for Test CouponsA 436 84 (2006)3Metric Equivalentsin.mm121312511238251NOTEThe length of the keel block shall be 6 in. (152 mm).FIG. 2 Keel
43、 Block for Test CouponsMetric Equivalentsin. mm in. mm0.005 0.13 0.50 12.70.01 2.5 2 50.818 3.2 214 57.238 9.5NOTEThe gage length and fillets shall be as shown but the ends maybe of any shape to fit the holders of the testing machine in such a way thatthe load shall be axial. The reduced section sha
44、ll have a gradual taper fromthe ends toward the center, with the ends 0.003 to 0.005 in. (0.08 to 0.13mm) larger in diameter than the center.FIG. 3 Standard Round Tension Test Specimen with 2-in. or50-mm Gage LengthA 436 84 (2006)4Metric Equivalentsin. mm in. mm0.005 0.13 1.0 25.40.007 0.18 114 31.8
45、0.252 6.40 1.4 35.60.357 9.07 134 44.4NOTE 1If desired, the length of the reduced section may be increasedto accommodate an extensometer.FIG. 4 Examples of Small-Size Specimens Proportional toStandard12-in. (12.7-mm) Round SpecimenFIG. 5 Sectioning Procedure for “Y” BlocksA 436 84 (2006)5ASTM Intern
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47、heir own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand shoul
48、d be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Stand
49、ards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).A 436 84 (2006)6
