1、Designation: A 47/A 47M 99 (Reapproved 2009)Standard Specification forFerritic Malleable Iron Castings1This standard is issued under the fixed designation A 47/A 47M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last
2、 revision. A number 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 Department of Defense.1. Scope1.1 This specification2covers ferritic mallea
3、ble castings forgeneral engineering usage at temperatures from normal ambi-ent to approximately 400C (750F).1.2 No precise quantitative relationship can be stated be-tween the properties of the iron in various locations of the samecasting and those of a test specimen cast from the same iron(see Appe
4、ndix X1).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 shall be used independently of the other. Combiningvalues from the two systems may result in non-conform
5、ancewith the standard.2. Referenced Documents2.1 ASTM Standards:3A 153/A 153M Specification for Zinc Coating (Hot-Dip) onIron and Steel HardwareA 247 Test Method for Evaluating the Microstructure ofGraphite in Iron CastingsA 644 Terminology Relating to Iron CastingsE8 Test Methods for Tension Testin
6、g of Metallic MaterialsE10 Test Method for Brinell Hardness of Metallic Materi-alsE18 Test Methods for Rockwell Hardness of MetallicMaterialsE 140 Hardness Conversion Tables for Metals RelationshipAmong Brinell Hardness, Vickers Hardness, RockwellHardness, Superficial Hardness, Knoop Hardness, andSc
7、leroscope Hardness2.2 Military Standard:4MIL-STD-129 Marking for Shipment and Storage2.3 Federal Standard:4Fed. Std. No. 123 Marking for Domestic Shipment (CivilianAgencies)3. Terminology3.1 DefinitionsDefinitions for many terms common toiron are found in Terminology A 644.4. Classification4.1 Casti
8、ngs ordered and produced under this specificationare classified under the following grades based on tests onseparately cast test bars. Separately cast test bars shall bepoured from the same lot of iron as the castings they representand shall be heat treated with those castings except as providedin 7
9、.2.3.4.1.1 Grade 32510 Grade 22010:4.1.1.1 The first three digits of the grade designation indi-cate the minimum yield strength (3100 psi MPa) and the lasttwo digits indicate the minimum elongation (% in 2 in. 50mm).5. Ordering Information5.1 The purchase order for castings ordered under thisspecifi
10、cation shall state the specification designation, the yearin which the specification was issued, and the grade ofmalleable iron to be supplied. Any option or special additionsto the basic requirements of this specification shall be clearlyand fully stipulated.6. Chemical Composition6.1 The chemical
11、composition of the iron shall be such as toproduce the structural and mechanical properties required bythis specification.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.
12、Current edition approved May 1, 2009. Published August 2009. Originallyapproved in 1984. Last previous edition approved in 2004 as A 47/A 47M 99(2004).2For ASME Boiler and Pressure Vessel Code applications see related Specifi-cation SA-47 in Section II of that code.3For referenced ASTM standards, vi
13、sit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.4Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Av
14、e., Philadelphia, PA 19111-50981Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.7. Mechanical Properties7.1 Factors influencing the properties of castings and theirrelationship to those of test specimens and separate testcastings are
15、discussed in Appendix X1.7.2 Tension Test Specimens:7.2.1 The tension test specimens shall be cast to the formand dimensions shown in Fig. 1 or Fig. 2, in the same kind ofmolding material used for the production castings. At leastthree such specimens shall be cast from a representative ladleof iron
16、either from each batch-melted heat or, in continuousmelting, from each 4-h pour period during which the purchas-ers castings were poured, or as otherwise agreed uponbetween manufacturer and purchaser.7.2.2 All test specimens shall be suitably identified with thedesignation of either the batch-melted
17、 heat or the pour periodof a continuous heat.7.2.3 All test specimens shall be heat treated in the sameproduction furnaces and in the same cycles as the castings theyrepresent. However, in those instances wherein the criticalsections of the production castings differ appreciably from thatof the cent
18、ral portion of the test specimens, the time cycle fortempering the test specimens may be altered from that of theproduction lot in order to obtain similar microstructures orhardness, or both, in both specimen and castings. In such casesthe hardness of the specimens shall be tested and reportedalong
19、with the tensile test results.7.2.4 The tension test is usually performed on unmachinedspecimens. However, for referee work, the specimen may bemachined from the standard cast bar to the dimensions shownin Fig. 3.7.3 Tension Test Method:7.3.1 The gage length of the standard tension specimen shallbe
20、2.00 6 0.01 in. 50.0 6 0.3 mm.7.3.2 The diameter used to compute the cross-sectional areashall be the average between the largest and smallest diametersin that section of the 2-in. 50-mm gage length having thesmallest diameter and shall be measured to the nearest 0.001 in.0.2 mm. No cast bar having
21、a mean diameter less than 0.590in. 15.0 mm shall be accepted for test.7.3.3 After reaching a stress equivalent to approximatelyhalf of the anticipated yield stress, the speed of the movinghead of the testing machine shall not exceed 0.50 in./min 12.5mm/min through the breaking load.7.3.4 While the v
22、alues for yield point and yield strength arenot identical, they are sufficiently close for most applications offerritic malleable irons to be used interchangeably. They maybe determined by any of the approved techniques described inthe paragraphs on Determination of Yield Strength and YieldPoint of
23、Test Methods E8.If determined as yield strength, thatstress producing an extension under load of 0.01 in. 0.25 mmover the 2-in. 50-mm gage length (for example, 0.5 %extension) or an offset of 0.2 % shall be taken as the yieldstress, which shall be converted to yield strength by dividingby the origin
24、al cross-sectional area of the gage length found inaccordance with 7.3.2. It shall be reported to the nearest 100psi MPa. In referee work, yield strength shall be determinedas the stress that produces an extension under load of 0.5 % ofthe gage length.7.3.5 The tensile strength shall be the maximum
25、loadcarried by the specimen during the test divided by the originalcross-sectional area of the gage length, as found in accordancewith 7.3.2. It shall be reported to the nearest 100 psi MPa.7.3.6 The elongation is the increase in gage length afterfracture of a tensile specimen, measured to the neare
26、st 0.01 in.FIG. 1 Tension Test SpecimenNOTE 1Modifications may be made in the dimensions indicatedabove for those details of the specimen outside of the gage length asrequired by testing procedure and equipment.FIG. 2 Alternative Unmachined Tension Test SpecimenNOTE 1The gage length and fillets shal
27、l be as shown, but the endsmay be of any shape to fit the holders of the testing machine in such a waythat the load shall be axial. The reduced section shall have a gradual taperfrom the ends toward the center, with the ends 0.003 to 0.005 in. 0.08 to0.13 mm larger in diameter than the center.FIG. 3
28、 Machined Tension Test SpecimenA 47/A 47M 99 (2009)20.25 mm, expressed as a percentage of the original gagelength. It shall be reported to the nearest 0.5 %.7.4 Retesting:7.4.1 If, after testing, a specimen shows evidence of adefect, another tension test may be made on a companionspecimen. Also, a r
29、etest shall be permitted whenever fractureoccurs outside the central 50 % of the gage length.7.4.2 If the results of a valid test fail to conform to therequirements of this specification, two retests shall be made. Ifeither retest fails to meet the specification, the castings repre-sented by these t
30、est specimens shall be rejected. A valid test isone wherein the test specimen has been properly prepared andappears to be sound and on which the approved test procedurehas been followed.7.4.3 If sufficient companion test bars are unavailable, themanufacturer shall have the option of testing a specim
31、en cutfrom a representative casting. Therefore, as stated in X1.3, themechanical properties of such tension test specimen removedfrom a production casting will not necessarily correspond tothose of a standard separately cast test specimen, the values inTable 1 do not apply. Instead, the mechanical p
32、roperties of thetest specimen from the casting must equal or exceed theaverage of those from similar test specimens removed from thesame location from two castings of the same design whereseparately cast test bars meet the requirements of Table 1.7.4.4 If the first test results indicate that a rehea
33、t treatmentis needed to meet the test requirements, the entire lot ofcastings and the representative test specimens shall be reheattreated together. Testing shall then be repeated in accordancewith 7.4.1-7.4.3.7.4.5 The results of all tests, including retests, shall beposted in permanent record, whi
34、ch shall state any abnormali-ties observed during the test and in the fractured ends. Suchrecords shall be kept for at least 1 year after shipment of theproduction castings and shall be available for examination bythe purchaser or by his authorized representative.7.4.6 If not covered in the purchase
35、 agreement, the fre-quency of tension testing shall be in accordance with 7.2.1 andsufficiently often to ensure uniformity of product and compli-ance with minimum test requirements.7.4.7 Tension test results, obtained in accordance with theabove subsections, must conform to the values of Table 1 for
36、acceptance under this specification except as provided in 7.4.3.7.4.8 When agreed upon between manufacturer and pur-chaser, tested specimens or unbroken test bars shall be pre-served by the manufacturer for a period of three months afterthe date of the test report.7.5 Hardness TestIf the purchase ag
37、reement requireshardness testing, the acceptable hardness range shall be statedand a test location clearly shown on the covering drawing(s).7.5.1 Hardness Test MethodThe Brinell method of hard-ness testing in accordance with Test Method E10 shall beemployed whenever possible.7.5.2 For castings of su
38、ch size or shape that do not permitBrinell testing with the standard 3000-kgf load, the 500 kgfmay be employed, the hardness number being reported as HB10/500/15. In very unusual cases where it is impossible to usethe Brinell method, the Rockwell test may be substituted, usingTest Methods E18with an
39、 appropriate Rockwell scale. Con-versions of hardness values from one method to anotheraccording to Hardness Conversion Tables E 140, which doesnot specifically cover cast irons, are approximate only and,therefore, are generally inadvisable.7.5.3 Sufficient material shall be removed from the castsur
40、face to ensure that the measured surface is representative.7.5.4 Sampling procedures and the frequency of hardnesstesting shall be fully detailed on the purchase agreement.Otherwise, hardness tests shall be performed at the discretionof the producer.7.5.5 Castings failing to conform to the required
41、hardnessrange may be reheat treated and retested. If after reheat treatingthey still fail the hardness requirements, they shall be rejected.7.5.6 Typical hardness maximums for this grade of mal-leable iron are listed in Table 2.8. Microstructure Requirements8.1 The microstructure of the malleable ir
42、on shall consist oftemper carbon nodules distributed through a ferritic matrix andshall be free of excessive pearlite, massive carbides, andprimary graphite.8.2 When agreed upon by the purchaser and producer, themaximum decarburization at any as-cast surface after heattreatment may be stipulated in
43、writing, as measured by visualdepletion of combined carbon after polishing, etching in nital,and viewing at 1003.8.3 In reference work, the metallographic practice recom-mended in Test Method A 247 shall be followed.9. Soundness Requirements9.1 All castings, on visual examination, shall be sound and
44、free of obvious shrinkage and porosity.9.2 If the purchaser requires soundness tests to be per-formed, it shall be so stated in the purchase agreement, and themethod and soundness requirements shall be detailed.10. Dimensional Requirements10.1 The castings shall conform to the dimensions given ondra
45、wings furnished by the purchaser, or to the dimensionsestablished by the pattern equipment supplied by the purchaser,or as agreed upon in specific cases to gages supplied by thepurchaser. Variations in any solid dimensions will be permitted,as shown in Table 3, unless otherwise agreed upon by thefou
46、ndry and purchaser.TABLE 1 Tension Test RequirementsInch-Pound GradesEnglishGradeTensile Strength,min, psiYield Strength,min, psiElongation in2 in, min, %32510 50 000 32 500 10Metric GradesMetricGradeTensile Strength,min, MPaYield Strengthmin, MPaElongation in50 mm, min, %22010 340 220 10TABLE 2 Typ
47、ical HardnessInch-Pound GradeMetric GradeHardness, maximumHBIndentation ValueDiameters, mm325 10 22010 156 4.8A 47/A 47M 99 (2009)311. Workmanship, Finish and Appearance11.1 The surface of the casting shall be inspected visually,particularly in critical areas, for such surface defects as cracks,hot
48、tears, adhering sand and scale, cold shuts, and gas holes.11.2 No repairing, plugging, or welding of any kind shall bepermitted unless written permission is granted by the pur-chaser.11.3 Castings that have been repaired by welding shall bereannealed so that their microstructure will comply withSect
49、ion 8.12. Responsibility for Inspection12.1 Unless otherwise specified in the contract or purchaseorder, the manufacturer shall be responsible for carrying out allthe tests and inspections required by this specification, usinghis own or other reliable facilities, and he shall maintaincomplete records of all such tests and inspections. Such recordsshall be available for review by the purchaser.12.2 The purchaser reserves the right to perform any inspec-tion set forth in the specification where such inspections aredeemed necessary to ensure th
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