1、Designation: A 47/A 47M 99 (Reapproved 2004)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 (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 specification2covers ferritic malle
3、able 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 App
4、endix X1).1.3 The values stated in either inch-pound units or SI unitsare to be regarded separately as standard. Within the text, theSI units are shown in brackets. The values stated in eachsystem are not exact equivalents; therefore, each system shallbe used independently of the other. Combining va
5、lues from thetwo systems may result in nonconformance with the specifi-cation.2. Referenced Documents2.1 ASTM Standards:3A 153 Specification for Zinc Coating (Hot-Dip) on Iron andSteel HardwareA 247 Test Method for Evaluating the Microstructure ofGraphite in Iron CastingsA 644 Terminology Relating t
6、o Iron CastingsE 8 Test Methods for Tension Testing of Metallic MaterialsE 10 Test Method for Brinell Hardness of Metallic Materi-alsE 18 Test Methods for Rockwell Hardness and RockwellSuperficial Hardness of Metallic MaterialsE 140 Hardness Conversion Tables for Metals RelationshipAmong Brinell Har
7、dness, Vickers Hardness, RockwellHardness, Superficial Hardness, Knoop Hardness, andScleroscope 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
8、for many terms common toiron are found in Terminology A 644.4. Classification4.1 Castings 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 casti
9、ngs they representand shall be heat treated with those castings except as providedin 7.2.3.4.1.1 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
10、).5. Ordering Information5.1 The purchase order for castings ordered under thisspecification 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 speci
11、fication shall be clearlyand fully stipulated.6. Chemical Composition6.1 The chemical composition of the iron shall be such as toproduce the structural and mechanical properties required bythis specification.7. Mechanical Properties7.1 Factors influencing the properties of castings and theirrelation
12、ship to those of test specimens and separate testcastings are discussed in Appendix X1.1This 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.Current edition approved Oct. 1, 20
13、04. Published October 2004. Originallyapproved in 1984. Last previous edition approved in 1999 as A 47/A 47M 99.2For ASME Boiler and Pressure Vessel Code applications see related Specifi-cation SA-47 in Section II of that code.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orc
14、ontact 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 Ave., Philadelphia, PA 19111-50981Copyrig
15、ht ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.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 castin
16、gs. At leastthree such specimens shall be cast from a representative ladleof iron 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 spe
17、cimens shall be suitably identified with thedesignation of either the batch-melted 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 c
18、riticalsections of the production castings differ appreciably from thatof the central 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 casti
19、ngs. In such casesthe hardness of the specimens shall be tested and reportedalong 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 T
20、ension Test Method:7.3.1 The gage length of the standard tension specimen shallbe 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
21、diameter and shall be measured to the nearest 0.001 in.0.2 mm. No cast bar having 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 sh
22、all not exceed 0.50 in./min 12.5mm/min through the breaking load.7.3.4 While the values 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 technique
23、s described inthe paragraphs on Determination of Yield Strength and YieldPoint of Test Methods E 8. 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
24、the yieldstress, which shall be converted to yield strength by dividingby the original 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 un
25、der load of 0.5 % ofthe gage length.7.3.5 The tensile strength shall be the maximum 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 th
26、e increase in gage length afterfracture of a tensile specimen, measured to the nearest 0.01 in.0.25 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 ma
27、y be made on a companionspecimen. Also, a retest shall be permitted whenever fractureoccurs outside the central 50 % of the gage length.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
28、 by testing procedure and equipment.FIG. 2 Alternative Unmachined Tension Test SpecimenNOTE 1The gage length and fillets shall 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 ta
29、perfrom 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 Machined Tension Test SpecimenA 47/A 47M 99 (2004)27.4.2 If the results of a valid test fail to conform to therequirements of this specification, two retests shall be made. I
30、feither retest fails to meet the specification, the castings repre-sented by these test 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
31、test bars are unavailable, themanufacturer shall have the option of testing a specimen 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 separat
32、ely cast test specimen, the values inTable 1 do not apply. Instead, the mechanical properties 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 me
33、et the requirements of Table 1.7.4.4 If the first test results indicate that a reheat 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
34、The results of all tests, including retests, shall beposted in permanent record, which 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 byth
35、e purchaser or by his authorized representative.7.4.6 If not covered in the purchase 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, obtaine
36、d in accordance with theabove subsections, must conform to the values of Table 1 foracceptance 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
37、of three months afterthe date of the test report.7.5 Hardness TestIf the purchase agreement 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 accorda
38、nce with Test Method E 10 shall beemployed whenever possible.7.5.2 For castings of such 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 uset
39、he Brinell method, the Rockwell test may be substituted, usingTest Methods E 18 with an 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
40、, are generally inadvisable.7.5.3 Sufficient material shall be removed from the castsurface 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 perfor
41、med at the discretionof the producer.7.5.5 Castings failing to conform to the required 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 lis
42、ted in Table 2.8. Microstructure Requirements8.1 The microstructure of the malleable iron 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, them
43、aximum decarburization at any as-cast surface after heattreatment may be stipulated in 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 follow
44、ed.9. Soundness Requirements9.1 All castings, on visual examination, shall be sound andfree 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
45、. Dimensional Requirements10.1 The castings shall conform to the dimensions given ondrawings 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 d
46、imensions will be permitted,as shown in Table 3, unless otherwise agreed upon by thefoundry and purchaser.11. 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 tears, adhering sand and
47、scale, cold shuts, and gas holes.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
48、 10TABLE 2 Typical HardnessInch-Pound GradeMetric GradeHardness, maximumHBIndentation ValueDiameters, mm325 10 22010 156 4.8A 47/A 47M 99 (2004)311.2 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 r
49、epaired by welding shall bereannealed so that their microstructure will comply withSection 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
