1、Designation: A 732/A732M 05Standard Specification forCastings, Investment, Carbon and Low Alloy Steel forGeneral Application, and Cobalt Alloy for High Strength atElevated Temperatures1This standard is issued under the fixed designation A 732/A732M; the number immediately following the designation i
2、ndicates the yearof original adoption or, in the case of revision, the year of last 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.1. Scope*1.1 This specification covers carbon and
3、low-alloy steel andcobalt alloy castings made by the investment casting process.1.2 Fifteen grades of steel and two cobalt alloy grades arecovered.1.3 Supplementary requirements of an optional nature areprovided for use at the option of the purchaser. The supple-mentary requirements shall apply only
4、 when specified indi-vidually by the purchaser in the purchase order or contract.1.4 This specification is expressed in both inch-pound unitsand SI units; however, unless the purchase order or contractspecifies the applicable M specification designation (SI units),the inch-pound units shall apply. T
5、he values stated in eitherinch-pound units or SI units are to be regarded separately asstandard. Within the text, the SI units are shown in brackets.The values in each system may not be exact equivalents;therefore, each system shall be used independently of the other.Combining values from the two sy
6、stems may result in noncon-formance with this standard.2. Referenced Documents2.1 ASTM Standards:2A 941 Terminology Relating to Steel, Stainless Steel, Re-lated Alloys, and FerroalloysA 957 Specification for Investment Castings, Steel andAlloy, Common Requirements, for General Industrial UseA 994 Gu
7、ide for Editorial Procedures and Form of ProductSpecifications for Steel, Stainless Steel, and RelatedAlloysA 997 Practice for Investment Castings, Surface AcceptedStandards, Visual ExaminationE21 Test Methods for Elevated Temperature Tension Testsof Metallic MaterialsE 139 Practice for Conducting C
8、reep, Creep-Rupture, andStress-Rupture Tests of Metallic Materials3. Ordering Information3.1 Orders for castings under this specification shouldinclude the following information:3.1.1 Quantity,3.1.2 ASTM designation and issue date,3.1.3 Grade designation (Tables 1 and 2), and3.1.4 Description of cas
9、ting by part, pattern, or drawingnumber. (Dimensional tolerances and machined surfaces shallbe indicated on the casting drawing.).3.2 The purchaser should specify any of the followinginformation to describe adequately the desired material:3.2.1 Heat-treat condition (see 5.1 and 5.2),3.2.2 Repair wel
10、ding (see Section 8 and SpecificationA 957),3.2.3 Source inspection, if any (see Specification A 957),and3.2.4 Supplementary requirements required (marking, certi-fication, mechanical properties, NDT, and the like).4. General Requirements4.1 Material furnished to this specification shall conform tot
11、he requirements of Specification A 957, including any supple-mentary requirements that are indicated on the purchase order.Failure to comply with the requirements of SpecificationA 957constitutes nonconformance with this specification. In case ofconflict of this specification and Specification A 957
12、, thisspecification shall prevail.5. Heat Treatment5.1 Steel castings shall be heat treated either by full anneal-ing, normalizing, normalizing and tempering, or quenching andtempering to obtain the specified properties or other propertiesthat have been agreed upon within each grade. In this latteri
13、nstance, Supplementary Requirement S23 shall be used.5.1.1 Heat treatment shall be performed after the castingshave been allowed to cool below the transformation range.1This specification is under the jurisdiction of ASTM committee A01 on Steel,Stainless Steel and Related Alloys and is the direct re
14、sponsibility of SubcommitteeA01.18 on Castings.Current edition approved Jan. 1, 2005. Published January 2005. Originallyapproved in 1976. Last previous edition approved in 2002 as A 732/A 732M 02.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at
15、 serviceastm.org. For Annual Book of ASTMStandards volume information, 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
16、, United States.5.2 Cobalt alloy castings shall be supplied in the as-castcondition unless otherwise agreed upon by supplier and pur-chaser.5.3 Definitions of terms relating to heat treatment shall be inaccordance with Terminology A 941.6. Chemical Composition6.1 The castings shall conform to the re
17、quirements forchemical composition specified in Table 1 and Table 2.7. Quality7.1 The surface of the casting shall be examined visually tomeet the requirements of PracticeA 997.Acceptance criteria tobe mutually agreed upon between supplier and purchaser.7.2 The castings shall not be peened or plugge
18、d or impreg-nated.8. Repair by Welding8.1 Welding shall be accomplished with a filler metal thatproduces a weld deposit with a chemical composition similar tothe casting. Castings ordered in the annealed condition or forsubsequent hardening shall be annealed after weld repairs.Castings ordered heat
19、treated shall be post weld heat treated inaccordance with the qualified welding procedure after weldrepairs with the exception of Grades 1A and 2A where postweld heat treatment is optional.8.2 Welds shall be inspected to the same quality standardsas are used to inspect the castings.9. Keywords9.1 al
20、loy steel; carbon steel; cobalt alloys; investment cast-ings; steel castingsTABLE 1 Chemical RequirementsGrade 1A 2A,2Q 3A,3Q 4A,4Q 5N 6N 7Q 8QType Low CarbonIC 1020AMediumCarbonIC 1030MediumCarbonIC 1040MediumCarbonIC 1050VanadiumIC 6120ManganeseMolybdenumIC 4020ChromiumMolybdenumIC 4130ChromiumMol
21、ybdenumIC 4140Carbon 0.15 to 0.25 0.25 to 0.35 0.35 to 0.45 0.45 to 0.55 0.30 max 0.35 max 0.25 to 0.35 0.35 to 0.45Manganese 0.20 to 0.60 0.70 to 1.00 0.70 to 1.00 0.70 to 1.00 0.70 to 1.00 1.35 to 1.75 0.40 to 0.70 0.70 to 1.00Phosphorus, max 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04Sulfur, max 0.04
22、5 0.045 0.045 0.045 0.045 0.045 0.045 0.045Silicon 0.20 to 1.00 0.20 to 1.00 0.20 to 1.00 0.20 to 1.00 0.20 to 0.80 0.20 to 0.80 0.20 to 0.80 0.20 to 0.80NickelChromium 0.80 to 1.10 0.80 to 1.10Molybdenum 0.25 to 0.55 0.15 to 0.25 0.15 to 0.25Vanadium 0.05 to 0.15Residual Elements:Copper 0.50 0.50 0
23、.50 0.50 0.50 0.50 0.50 0.50Nickel 0.50 0.50 0.50 0.50 0.50 0.50Chromium 0.35 0.35 0.35 0.35 0.35Molybdenum + Tungsten 0.25 0.25Tungsten 0.10 0.10 0.10 0.25 0.10 0.10Total content of theseresidual elements1.00 1.00 1.00 0.60 1.00 1.00 0.60 1.00Grade 9Q 10Q 11Q 12Q 13Q 14Q 15AType Chrome NickelMolybd
24、enumIC 4330Chrome NickelMolybdenumIC 4340Nickel Molyb-denumIC 4620ChromiumVanadiumIC 6150Chrome NickelMolybdenumIC 8620Chrome NickelMolybdenumIC 8630ChromiumIC 52100Carbon 0.25 to 0.35 0.35 to 0.45 0.15 to 0.25 0.45 to 0.55 0.15 to 0.25 0.25 to 0.35 0.95 to 1.10Manganese 0.40 to 0.70 0.70 to 1.00 0.
25、40 to 0.70 0.65 to 0.95 0.65 to 0.95 0.65 to 0.95 0.25 to 0.55Phosphorus, max 0.04 0.04 0.04 0.04 0.04 0.04 0.04Sulfur, max 0.045 0.045 0.045 0.045 0.045 0.045 0.045Silicon 0.20 to 0.80 0.20 to 0.80 0.20 to 0.80 0.20 to 0.80 0.20 to 0.80 0.20 to 0.80 0.20 to 0.80Nickel 1.65 to 2.00 1.65 to 2.00 1.65
26、 to 2.00 0.40 to 0.70 0.40 to 0.70Chromium 0.70 to 0.90 0.70 to 0.90 0.80 to 1.10 0.40 to 0.70 0.40 to 0.70 1.30 to 1.60Molybdenum 0.20 to 0.30 0.20 to 0.30 0.20 to 0.30 0.15 to 0.25 0.15 to 0.25Vanadium 0.15 minResidual Elements:Copper 0.50 0.50 0.50 0.50 0.50 0.50 0.500.50 0.50Chromium 0.35Molybde
27、num + Tungsten 0.10Tungsten 0.10 0.10 0.10 0.10 0.10 0.10Total content of theseresidual elements0.60 1.00 1.00 1.00 1.00 1.00 0.60AInvestment Casting (IC) numbers are to be used only for nomenclature comparison.TABLE 2 Chemical Requirements-Cobalt AlloysGrade 21 31Carbon 0.200.30 0.450.55Manganese,
28、max. 1.00 1.00Silicon, max 1.00 1.00Phosphorus, max 0.040 0.040Sulfur, max 0.040 0.040Chromium 25.029.0 24.526.5Nickel 1.73.8 9.511.5Cobalt remainder remainderMolybdenum 5.06.0 .Tungsten . 7.08.0Iron, max. 3.00 2.00Boron 0.007 max 0.0050.015A 732/A732M 052SUPPLEMENTARY REQUIREMENTSThe following supp
29、lementary requirements shall not apply unless specified in the purchase order. Alist of standardized supplementary requirements for use at the option of the purchaser is included inSpecification A 957. Those ordinarily considered suitable for use with this specification are givenbelow, together with
30、 additional supplementary requirements that are applicable only to thisspecification. Other supplementary requirements enumerated in Specification A 957 may be used withthis specification upon agreement between supplier and purchaser.S1. Magnetic Particle InspectionS2. Radiographic InspectionS3. Liq
31、uid Penetrant InspectionS6. CertificationS7. Prior Approval of Major Weld RepairsS8. MarkingS13. Unspecified ElementsS16. Weld Repair ChartsS19. DecarburizationS23. Mechanical PropertiesS23.1 Mechanical properties other than those specified inTable S24 may be ordered for each of the grades. Theprope
32、rties shall be agreed upon between the supplier and thepurchaser.S24. Tension Test (Castings Heat Treated by Supplier)S24.1 Tensile properties shall be determined from materialrepresenting each re-melted heat. The results shall conform tothe requirements specified in Table S24, or to properties agre
33、edupon, and shall be reported to the purchaser or his representa-tive. See Specification A 957 for additional details and require-ments.S25. Tension Test (Castings Heat Treated by Purchaser)S25.1 The supplier shall heat treat a tension specimen froma re-melted heat of same primary heat to determine
34、whether thecastings are capable of being heat treated to the specifiedproperties. The results shall conform to the requirementsspecified in Table S24, or to properties agreed upon, and shallbe reported to the purchaser or his representative. See Speci-ficatioin A 957 for additional details and requi
35、rements.S26. High Temperature Tension TestS26.1 High-temperature tension tests shall be required whenspecified in the inquiry, contract, or order. When so specified,the properties obtained shall be reported to the purchaser or hisrepresentative and shall conform to the requirements pre-scribed in Ta
36、ble S26. The tension test shall be performed inaccordance with Test Methods E21.S27. Stress Rupture TestS27.1 Stress rupture tests shall be required when specifiedin the inquiry, contract, or order. When so specified, theproperties obtained shall be reported to the purchaser or hisTABLE S24 Tensile
37、RequirementsGrade Tensile strength, min Yield strength, min Elongation, in 2-in.50-mm or 4diametersHeatTreatmentksi MPa ksi MPa1A 60 414 40 276 24 AA2A 65 448 45 310 25 A2Q 85 586 60 414 10 QtB3A 75 517 48 331 25 A3Q 100 689 90 621 10 Qt4A 90 621 50 345 20 A4Q 125 862 100 689 5 Qt5N 85 586 55 379 22
38、 NtC6N 90 621 60 414 20 Nt7Q 150 1030 115 793 7 Qt8Q 180 1241 145 1000 5 Qt9Q 150 1030 115 793 7 Qt10Q 180 1241 145 1000 5 Qt11 120 827 100 689 10 Qt12Q 190 1310 170 1172 4 Qt13Q 105 724 85 586 10 Qt14Q 150 1030 115 793 7 Qt15AD. . . . . AAAnnealed.BQuenched and tempered.CNormalized and tempered.DHa
39、rdness Rockwell B, 100 max.A 732/A732M 053representative and shall conform to the requirements pre-scribed in Table S27. The stress rupture test shall be performedin accordance with Practice E 139.APPENDIX(Nonmandatory Information)X1. GUIDE TO CLASSIFICATION OF COBALT ALLOY CASTINGSX1.1 This guide i
40、s appended to the specification as a sourceof information; it is not mandatory and does not form a part ofthe specification.X1.1.1 This specification itself is intended to provide boththe manufacturer and the purchaser of alloy castings with ameans of production control on the basis of acceptance th
41、roughmutually acceptable, sound, standard requirements.X1.1.2 This guide has been prepared as an aid to prospec-tive users of alloy castings covered by the specification indetermining the classification best suited for a particularapplication with due consideration to the particular require-ments fo
42、r that application.X1.2 Stress for DesignThe old method of basing designcalculations on 50 % of the limiting creep stress is conserva-tive, but it is relatively crude and has the disadvantage that theresulting stress values do not have a consistent relation to lifeexpectancy. Design with the stress
43、that should produce rupturein 100 000 h is frequently satisfactory, though it should berecognized that this is an extrapolated value and provides noassurance that the installation will actually endure for this time.Among the factors that can result in shorter life are reductionof the effective cross
44、-sectional area by hot-gas corrosion,thermal stresses superimposed on the normal working stresses,and overheating. Usually overheating is the most serious ofthese, since in general a 200F 110C increase in temperaturewill cut the rupture strength in half.X1.3 Grade 21 (Cobalt-base27 % Cr, 5.5 % Mo, 2
45、.8 %Ni):X1.3.1 This grade is resistant to oxidizing and reducingatmospheres at temperatures up to 2100F 1150C. The alloyhas good strength at elevated temperatures and is used in manyapplications where resistance to thermal shock is important.The alloy can be produced as sand, shell, or investmentcas
46、tings.X1.3.2 CompositionThis grade is of the austenitic, solidsolutioning type and possesses its basic strength characteristicswithout the need of heat treatment. However, the alloy is sodesigned that aging occurs in the 1300 to 2100F 700 to1150C range by the formation of carbides, thus strengthenin
47、gthe alloy in service. The high chromium imparts the excellentoxidation resistance of the alloy and contributes, along with themolybdenum, to the strength of the alloy.X1.3.3 Mechanical PropertiesThis grade can be used forapplications of high stress up to 1500F 815C and moderatestrength requirements
48、 to 2100F 1150C. The average as-casttensile strength at 1500F is 62 000 psi 430 MPa with 16 %elongation. The alloy exhibits good impact strength even in theage-strengthened condition. The average charpy V-notch im-pact strength after aging is above 20 ftlb 27 J in the 1200 to1800F 650 to 980C range.
49、 Table X1.1 contains typicalstress-rupture data for this alloy.X1.3.4 ApplicationsThis grade can be used for applica-tions of high stress up to 1500F and for moderate strengthrequirements up to 2100F. In the past, it has been usedTABLE S26 Elevated-Temperature Tensile RequirementsGrade 21 31Condition as cast as castTest temperature:F 1500 1500C 820 820Tensile strength, min:ksi 52.0 55.0MPa 360 380Elongation in 4D,min,% 10 10TABLE S27 Stress Rupture RequirementsG
