1、Designation: A447/A447M 10Standard Specification forSteel Castings, Chromium-Nickel-Iron Alloy (25-12 Class),for High-Temperature Service1This standard is issued under the fixed designation A447/A447M; the number immediately following the designation indicates the yearof original adoption or, in the
2、 case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers iron-base, heat-resisting alloycastings of the 25 % chromium
3、, 12 % nickel class, intended forstructural elements, containers, and supports in electric fur-naces, petroleum still tube supports, and for similar applica-tions up to 2000F 1095C. The purchaser should inform themanufacturer when the service temperatures are to exceed1800F 980C.1.2 In the absence o
4、f significant proportions of elementsother than those prescribed in Section 4, the two types of alloyscovered by this specification may in general be distinguished asfollows:1.2.1 Type IAlloys characterized by relatively low limit-ing creep stress at temperatures between 1500 and 2000F 815and 1095C,
5、 and relatively high ductility at ordinary tempera-tures after aging for short periods at temperatures between1300 and 1500F 705 and 815C.1.2.2 Type IIAlloys having relatively high limiting creepstress but which may develop low ductility at ordinary tem-peratures when aged for short periods at tempe
6、ratures between1350 and 1500F 730 and 815C.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
7、 systems may result in non-conformancewith the standard.1.3.1 Within the text, the SI units are shown in brackets.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate s
8、afety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2A781/A781M Specification for Castings, Steel and Alloy,Common Requirements, for General Industrial UseA800/A800M Practice for Steel Casting, Austenitic Alloy,
9、Estimating Ferrite Content ThereofE8 Test Methods for Tension Testing of Metallic MaterialsE21 Test Methods for Elevated Temperature Tension Testsof Metallic Materials3. General Conditions for Delivery3.1 Material furnished to this specification shall conform tothe requirements of Specification A781
10、/A781M, including anysupplementary requirements that are indicated in the purchaseorder. Failure to comply with the general requirements ofSpecification A781/A781M constitutes nonconformance withthis specification. In case of conflict between the requirementsof this specification and Specification A
11、781/A781M, thisspecification shall prevail.4. Process4.1 The alloy for the castings shall be made by the electric-furnace process or by any other process approved by thepurchaser.5. Heat Treatment5.1 Except as otherwise agreed upon between the manufac-turer and the purchaser, the manufacturer shall
12、not be requiredto heat treat the castings.1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.18 on Castings.Current edition approved Oct. 1, 2010. Published November 2010. Originallyappro
13、ved in 1944. Redesignated as A447 in 1961. Last previous edition approved in2007 as A447/A447M 93 (2007). DOI: 10.1520/A0447_A0447M-10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume inf
14、ormation, refer to the standards Document Summary page onthe ASTM website.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6. Chemical Composition6.1 The castings shall
15、 conform to the requirements of Table1 as to chemical composition.7. Sampling7.1 Material for the tests specified in Sections 10, 12, and 13may be taken from separately cast test blocks of a form such asthat shown in Fig. 1, from another type of test block, from thecastings, or from coupons attached
16、 to the castings, as may beagreed upon between the manufacturer and the purchaser.7.2 Material for the magnetic permeability test specimen(Section 11) may be taken, prior to heat treatment, from thesame coupon as the specimen for the tension test after aging;from suitable specimens cast as parts of
17、separately cast testblocks; or, by agreement between the manufacturer and thepurchaser, from castings representing the melt.7.3 In the case of castings for unusual or severe service, thetest coupons shall be attached to the castings at convenientlocations as may be agreed upon between the manufactur
18、er andthe purchaser.7.4 In all cases, it shall be the manufacturers duty toprovide a sufficient number of samples for the specified tests.8. Number of Tests8.1 The purchaser shall specify not more than two tests. Thetests shall be selected from the following list, with therestriction that not more t
19、han one of the tension tests at hightemperature (that is, 8.1.3 or 8.1.4) may be required:8.1.1 Tension test after aging,8.1.2 Magnetic permeability test,8.1.3 Stress-rupture test, and8.1.4 Short-time high-temperature tension test.9. Retests9.1 Mechanical TestsIf any of the specimens first chosenfor
20、 any of the mechanical tests agreed upon fail to conform tothe specified requirements, an additional specimen from thesame melt may be tested. This additional specimen shallconform to the requirements prescribed for the test in question.9.2 Magnetic TestIf the magnetic permeability of thespecimen fi
21、rst tested does not conform to the requirementprescribed in 11.1, three additional specimens from the samemelt may be tested. At least two of these shall conform to theprescribed requirement.10. Tensile Properties After Aging10.1 The tensile properties of the material after aging shallconform to the
22、 following requirements:Type I Type IITensile strength, min, ksi MPa 80 550 80 550Elongation in 2 in. 50 mm, min, % 9 410.2 Samples from which the tension specimens are to betaken shall be heated for 24 h at 1400 6 25F 760 6 14Cand allowed to cool at least down to 400F 205C at rates notexceeding 200
23、F 110C/h. The tension test specimens shallbe machined from the heat-treated sample, and shall conformto the dimensions shown in Fig. 1 of Test Methods E8.10.3 The tension test shall be made in accordance with TestMethods E8. The speed of head of the testing machine shall beso adjusted that the rate
24、of separation of the gage marks on thetest specimen shall not exceed 0.1 in. 3 mm/min.TABLE 1 Chemical RequirementsElement Composition, %NiA10.0014.00Cr 23.0028.00C 0.200.45N, max 0.20Mn, max 2.50Si, max 1.75P, max 0.030S, max 0.030Fe and other elements as may be agreed upon between themanufacturer
25、and the purchaserACommercial nickel usually carries a small amount of cobalt, and within theusual limits cobalt shall be counted as nickel.Metric Equivalentsin. mm in. mm18 3.2 312 88.912 12.7 4 101.61116 27.0 4116 103.2112 38.1 5 127.03 76.2 11 279.4NOTEPour through head; cover molten head with pow
26、dered charcoal,coke dust, etc., immediately after pouring, in order to keep head fluid aslong as possible.FIG. 1 Test Block for Tension Test SpecimenA447/A447M 10211. Magnetic Permeability11.1 The magnetic permeability of the material shall con-form to the following requirements:Magnetic Permeabilit
27、y,maxType I 1.70Type II 1.05NOTE 1The magnetic permeability test gives a qualitative indicationof the ferrite content for alloys falling within the range of chemicalcomposition specified in Section 6, excluding iron and other elements asmay be agreed upon. When special alloying elements are specifie
28、d, themagnetic permeability test is not recommended because its significancehas not yet been established for such alloys.11.2 The specimen shall be heated in air to 2000 6 25F1095 6 14C, held within this range for 24 h, and thenquenched in water. After quenching, all scale and superficialoxidized me
29、tal shall be removed in order to avoid errors thatmight arise from the presence of magnetizable oxides formedduring heating.11.3 Unless otherwise agreed upon between the purchaserand the manufacturer, the magnetic permeability shall bedetermined in accordance with Supplementary Requirement S1of Prac
30、tice A800/A800M.NOTE 2Where the test method used measures volume percent ferrite,conversion to magnetic permeability may be accomplished using thefollowing requirements:Volume, Ferrite, %,maxMagnetic Permeability,max181.051.7012. Stress-Rupture Test12.1 The following tensile stress shall be sustaine
31、d for atleast 16 h without rupturing the specimen:Tensile Stress,ksi MPaType IType II5 348 5512.2 The test specimen shall conform to the dimensionsshown in Fig. 1 of Test Methods E8.12.3 The specimen in the as-cast condition shall be mountedin the testing machine and held for1hat1600 6 10F 870 65.5C
32、. The specimen shall then be subjected to a steady tensileload while the temperature over the gage length is maintainedat 1600 6 10F 870 6 5.5C in an air atmosphere.13. Short-Time, High-Temperature Tensile Properties13.1 The short-time, high-temperature tensile propertiesshall conform to the followi
33、ng requirements:Tensile Strength, min, ksiMPaElongation in 2 in. 50 mm,min, %Type I as agreed upon betweenmanufacturer and purchaseras agreed upon betweenmanufacturer and purchaserType II 20 140 813.2 The test specimen shall conform to the dimensionsshown in Fig. 1 of Test Methods E8.13.3 The specim
34、en in the as-cast condition, that is, withoutany heat treatment after cooling from the casting temperature,shall be subjected to a short-time tension test during which thetemperature shall be maintained at 1600 6 10F 870 65.5C. The specimen shall be mounted in the testing furnaceand held within this
35、 range of temperature for 1 h, and the testload then applied.13.4 The test shall be made in accordance with Practice E21except that the speed of head of the testing machine shall be soadjusted that the rate of separation of the gage marks on the testspecimen shall not exceed 0.03 in. 0.8 mm/min.14.
36、Defective Test Specimens14.1 If any specimen shows defective machining or devel-ops flaws, it may be discarded and another specimen from thesame melt substituted.14.2 If any part of the fracture in any of the specimenssubjected to tension tests is more than34 in. 19.0 mm fromthe center of the gage l
37、ength as indicated by gage marks placedon the specimen before testing, another specimen may besubstituted.15. Repair by Welding15.1 Weld repairs shall be inspected to the same qualitystandards as are used to inspect the castings.15.2 When heat treatment is specified, the castings shall beheat treate
38、d after welding.16. Keywords16.1 ausenitic stainless steel; high temperature applications;stainless steel; steel castingsA447/A447M 103SUPPLEMENTARY REQUIREMENTSThe following supplementary requirements shall not be applied unless specified in the purchaseorder. A list of standardized supplementary r
39、equirements for use at the option of the purchaser isincluded in Specification A781/A781M. Those which are ordinarily considered suitable for use withthe specification are given below. Others enumerated in Specification A781/A781M may be used withthis specification upon agreement between manufacture
40、r and purchaser.S5. Examination of Weld PreparationS8. MarkingS6. CertificationAPPENDIX(Nonmandatory Information)X1. BIBLIOGRAPHYX1.1 The following selected bibliography is appended foruse by those who may be interested in gaining some informa-tion about the complex behavior of metals under stress a
41、televated temperatures. The bibliography is by no meanscomplete, but will serve as an introduction to the subject.(1) Brophy, G. R., and Furman, D. E., “The CyclicTemperature Acceleration of Strain in Heat Resisting Alloys,”Transactions, TA-SEA, Am. Soc. Metals, Vol 30, No. 4,December 1942, pp. 1115
42、1138.(2) Fellows, J. A., Cook, E., and Avery, H. S., “Precision inCreep Testing,” Metals Technology, METYA,Am. Inst. Miningand Metallurgical Engrs. Technical Publication 1443, Vol 9,No. 5, August 1942, pp. 115.(3) Avery, H. S., Cook, E., and Fellows, J. A., “EngineeringProperties of Heat-Resistant A
43、lloys,” Metals Technology ,METYA, Am. Inst. Mining and Metallurgical Engrs. TechnicalPublication 1480, Vol 9, No. 5, August 1942, pp. 122.(4) ASTM Recommended Practice E22, for ConductingLong-Time High-Temperature Tension Tests of Metallic Ma-terials, 1958 Book of ASTM Standards, Part 3.(5) Gow, J.
44、T., and Harder, O. E., “Balancing the Compo-sition of Cast 25 percent Chromium-12 percent Nickel TypeAlloys,” Transactions, TASEA, Am. Soc. Metals, Vol 30, No.4, December 1942, pp. 855935.(6) Gillett, H. W., “Some Things We Do not Know AboutCreep,” Henry Howe Memorial Lecture presented at a meetingo
45、f theAm. Inst. Mining and Metallurgical Engrs.,August 1939.(7) Tapsell, H. J., “Creep of Metals,” Humphrey Milford,Oxford University Press, London (1931).(8) Symposium on Effect of Temperature on the Propertiesof Metals, Am. Soc. Mech. Engrs. and ASTM (1931). (Sym-posium issued as a separate publica
46、tion, ASTM STP 12,ASTTA).(9) Compilation of Available High-Temperature CreepCharacteristics of Metals and Alloys, Joint Research Commit-tee on Effect of Temperature on the Properties of Metals (JointCommittee of Am. Soc. Mech. Engrs. and ASTM), March1938. ( ASTM STP 37, ASTTA).(10) Manjoine, M. J.,
47、“New Machines for Creep and Creep-Rupture Tests.”(Constant strain-rate tests) Transactions,TASEA, Am. Soc. Mech. Engrs., February 1945, pp. 111 and116.A447/A447M 104SUMMARY OF CHANGESCommittee A01 has identified the location of selected changes to this standard since the last issue(A447/A447M 93 (20
48、07) that may impact the use of this standard. (Approved Oct. 1, 2010.)(1) Changed the limits for S and P in Table 1.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly a
49、dvised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their 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 should be addressed to ASTM Internationa
