1、Designation: A 747/A 747M 07Standard Specification forSteel Castings, Stainless, Precipitation Hardening1This standard is issued under the fixed designation A 747/A 747M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of
2、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 iron-chromium-nickel-coppercorrosion-resistant steel castings, capable of being strength-e
3、ned by precipitation hardening heat treatment.1.2 These castings may be used in services requiring corro-sion resistance and high strengths at temperatures up to 600F315C. They may be machined in the solution-annealedcondition and subsequently precipitation hardened to the de-sired high-strength mec
4、hanical properties specified in TableS14.1 with little danger of cracking or distortion.1.3 The material is not intended for use in the solution-annealed condition.NOTE 1If the service environment in which the material is to be usedis considered conducive to stress-corrosion cracking, precipitation
5、hard-ening should be performed at a temperature that will minimize thesusceptibility of the material to this type of attack.1.4 Supplementary requirements of an optional nature areprovided for use at the option of the purchaser. The Supple-mentary requirements shall apply only when specified indi-vi
6、dually by the purchaser in the purchase order or contract.1.5 This specification is expressed in both inch-pound unitsand in SI units; however, unless the purchase order or contractspecifies the applicable M specification designation (SI units),the inch-pound units shall apply. The values stated in
7、eitherinch-pound units or SI units are to be regarded separately asstandard. Within the text, the SI units are shown in brackets.The values stated in each system may not be exact equivalents;therefore, each system shall be used independently of the other.Combining values from the two systems may res
8、ult in noncon-formance with the standard.2. Referenced Documents2.1 ASTM Standards:2A 370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA 781/A 781M Specification for Castings, Steel and Alloy,Common Requirements, for General Industrial UseA 957/A 957M Specification for Investm
9、ent Castings, Steeland Alloy, Common Requirements, for General IndustrialUse2.2 ASME Standard:3ASME Boiler and Pressure Vessel Code, SupplementaryRequirements S6, S14, and S273. General Conditions for Delivery3.1 Except for investment castings, castings furnished tothis specification shall be in acc
10、ordance with the requirementsof Specification A 781/A 781M, including any supplementaryrequirements that are indicated in the purchase order. Failure tocomply with the general requirements of Specification A 781/A 781M constitutes nonconformance with this specification. Incase of conflict between th
11、e requirements of this specificationand Specification A 781/A 781M, this specification shall pre-vail.3.2 Steel investment castings furnished to this specificationshall conform to the requirements of Specification A 957/A 957M, including any supplementary requirements that areindicated in the purcha
12、se order. Failure to comply with thegeneral requirements of Specification A 957/A 957M consti-tutes nonconformance with this specification. In case of con-flict between the requirements of this specification and Speci-fication A 957/A 957M, A 957/A 957M shall prevail.4. Ordering Information4.1 Order
13、s for material to this specification should includethe following:4.1.1 Quantity,4.1.2 Specification designation and date of issue,4.1.3 Grade designation Table 1, and4.1.4 Description of casting by part, pattern, or drawingnumber. (Dimensional tolerances and machined surfacesshould be indicated on t
14、he casting drawing).4.1.5 Heat treatment condition (SA, H900, and so forth), see5.2 and Table 2,4.1.6 Options in the specification, if any, in accordance with5.2 and Section 7, and1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is t
15、he direct responsibility of SubcommitteeA01.18 on Castings.Current edition approved June 1, 2007. Published July 2007. Originally approvedin 1977. Last previous edition approved in 2004 as A 747/A 747M 04.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer S
16、ervice at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American Society of Mechanical Engineers (ASME), ASMEInternational Headquarters, Three Park Ave., New York, NY 10016-5990, http:/www.asme.or
17、g.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.4.1.7 Supplementary requirements, if any, including thestandards of acceptance.4.1.8 Notice when the castings are to
18、be used in equipmentcovered by the ASME Boiler and Pressure Vessel Code,Supplementary Requirements S6, S14, and S27 are mandatoryand must be specified in the purchase order.5. Materials and Manufacture5.1 The steel shall be made by the electric furnace processwith or without separate refining such a
19、s argon-oxygen decar-burization (AOD).5.2 Heat TreatmentCastings may be given a homogeni-zation heat treatment in accordance with 5.2.1 at the suppliersoption or when specified by the purchaser (see S26) prior tosolution heat treatment. All castings, whether homogenized ornot, shall be given a solut
20、ion treatment in accordance with5.2.2 and unless ordered in the solution-annealed conditionshall be precipitation hardened to the ordered condition (Table1).5.2.1 Homogenization heat treatment shall consist of heat-ing the castings and test material to a minimum of 1900F1040C, holding for a minimum
21、of 112 h, and cooling tobelow 90F 30C.5.2.2 Solution annealing heat treatment shall consist ofheating the castings and test material to 1925F 6 50F1050C 6 30C, holding the 30 min/in. 1.2 min/mm ofsection but not less than 30 min, and cooling to below 90F30C.5.2.3 Temperature used for precipitation h
22、ardening shall bemaintained within the range of 625F 615C of that listed inTable 1 for the heat-treatment condition ordered. (See Note 1)5.2.4 When the order or contract specifies a minimumcolumbium content, the minimum precipitation hardeningtemperature shall be 925F 495C.6. Chemical Composition6.1
23、 The steel shall be in accordance with the requirementsas to chemical composition prescribed in Table 2.6.2 When the H900 condition is ordered, the minimumcolumbium content (Table 2) shall not apply. It is recom-mended that columbium other than that in revert material notbe added.7. Repair by Weldin
24、g7.1 Repairs shall be made only in one of the followingconditions: homogenized, solution annealed, H1100, H1150,H1150M, H1150DBL, or stress relieved at 1150F 6 25F620C 6 15C for a minimum of 4 h.7.2 Castings welded in one of the aged conditions noted in7.1 shall be post weld heat treated by the same
25、 aging treatmentused prior to welding, or, where necessary to meet mechanicalproperty requirements, shall be solution annealed and agedafter welding. Castings welded in the stress-relieved conditionshall receive the specification heat treatment after welding.8. Keywords8.1 precipitation hardening st
26、ainless steel; stainless steel;steel castingsTABLE 1 Precipitation Hardening Heat TreatmentA,BCondition PHCTemperature, FC Time, h and min Cooling TreatmentSA Not precipitation hardened (see 5.2.3)H900 900 480 1.5 air coolH925 925 495 1.5 air coolH1025 1025 550 4.0 air coolH1075 1075 580 4.0 air coo
27、lH1100 1100 595 4.0 air coolH1150 1150 620 4.0 air coolH1150M 1400 7601150 6202.04.0air coolair coolH1150 DBL 1150 6201150 6204.04.0air coolair coolAThe furnace and controls used shall be calibrated and capable of uniformity ofheating in order to ensure consistent results.BSee Note 1.C625F 15C.TABLE
28、 2 Chemical RequirementsAGradeUNSTypeCB7Cu-1J9218017-4CB7Cu-2J9211015-5Carbon 0.07 0.07Manganese 0.70 0.70Phosphorus 0.035 0.035Sulfur 0.03 0.03Silicon 1.00 1.00Chromium 15.5017.70 14.015.50Nickel 3.604.60 4.505.50Copper 2.503.20 2.503.20Columbium 0.150.35B0.150.35BNitrogenC0.05 0.05ALimits are perc
29、ent maximum unless shown as a range or stated otherwise.BSee 5.2.4 and 6.2. When the H900 condition is ordered, the minimumcolumbium content shall not apply.CTo be determined and reported when specified by the order or contract.A 747/A 747M 072SUPPLEMENTARY REQUIREMENTSAlist of standardized suppleme
30、ntary requirements for use at the option of the purchaser is describedin Specifications A 781/A 781M and A 957/A 957M. Those that are considered suitable for use withthis specification are listed below by title only.Additional supplementary requirements suitable for usewith this specification at the
31、 option of the purchaser are described below. One or more of thesupplementary requirements indicated below may be included in the purchasers order or contract.When so included, a supplementary requirement shall have the same force as if it were in the bodyof the specification. Supplementary requirem
32、ents details not fully described shall be agreed uponbetween the purchaser and the supplier, but shall not negate any of the requirements in the body ofthe specification.S1. Magnetic Particle ExaminationNOTE When CB7CU-1 alloy is inspected by magnetic particlemethod, false indications may be caused
33、by ferrite stringers or traces ofretained austenite in the microstructure. Liquid penetrant methods may beused to confirm the presence or absence of a discontinuity when suchindications are noted.S2. Radiographic ExaminationS3. Liquid Penetrant ExaminationS5. Examination of Weld PreparationS6. Certi
34、ficationS10. Hardness Test (Rockwell)S10.1 Rockwell hardness test shall be made from each heattreatment load for each heat. The results shall conform to therequirements in Table S14.1 and shall be reported to thepurchaser or his representative.S10.2 The test shall be conducted in accordance with Tes
35、tMethods and Definitions A 370.S13. Hardness Test (Brinell)S13.1 Brinell hardness test shall be made from each heat-treatment load for each heat. The results shall be in accordancewith the requirements in Table S14.1 and shall be reported tothe purchaser or his representative.S13.2 The test may be m
36、ade on the end of the tensionspecimen unless the order requires it to be made on a casting,in which case, where possible, the test shall be made on a bossor extension located on the casting suitable for testing in theBrinell tester.S13.3 The test shall be conducted in accordance with TestMethods and
37、 Definitions A 370.S14. Tension TestS14.1 Tensile properties shall be determined from materialrepresenting each heat. The bar from which the test specimenis taken shall be heat treated with production castings to thesame procedure as the castings it represents, unless the castingsare ordered in the
38、solution-annealed condition (5.2.2). Theresults shall be in accordance with the requirements specifiedin Table S14.1 and shall be reported to the purchaser or hisrepresentative.S14.2 When the contract or order specifies that the castingsare to be furnished in the solution-annealed condition, themanu
39、facturer shall test specimens representing the castings thathave been given the precipitation heat treatment specified bythe purchaser in accordance with Table 1.S14.3 Test coupons and tests shall be made in accordancewith Test Methods and Definitions A 370. Where possible, theTABLE S14.1 Mechanical
40、 PropertiesAlloyTypePH HeatTreatmentHardness,HBYield Strength0.2 % Offset, min,ksi MPaTensile Strength,ksi MPaElongation in 2in. 51 mm,min, %ACB7Cu-1 H900 375 min 145 1000 170 1170 5H925 375 min 150 1035 175 1205 5H1025 311 min 140 965 150 1035 9H1075 277 min 115 795 145 1000 9H1100 269 min 110 760
41、135 930 9H1150 269 min 97 670 125 860 10H1150MH1150 DBL310 max310 max.CB7Cu-2 H900 375 min 145 1000 170 1170 5H925 375 min 150 1035 175 1205 5H1025 311 min 140 965 150 1035 9H1075 277 min 115 795 145 1000 9H1100 269 min 110 760 135 930 9H1150 269 min 97 670 125 860 10H1150MH1150 DBL310 max310 max.AI
42、f sub-size tension test bars are used, the gage length/gage diameter ratio must be 4 to 1 to assure elongation values comparable with those of the standard testspecimen.A 747/A 747M 073standard 2-in. 50-mm gage length specimens shall be used.When investment castings are ordered, specimens may be cas
43、tto shape or machined from coupons to dimensions in accor-dance with Test Methods and Definitions A 370 or the ICI bar.Standard subsize specimens may be used when a 2-in. gagelength specimen is not feasible. When subsize specimens areused, the gage length shall be four times the gage diameter.S14.4
44、If any test specimen shows defective machining ordevelops flaws, it may be discarded and another specimensubstituted from the same lot. A retest shall be allowed if thepercentage elongation of any tension test specimen is less thanthat specified in Table S14.1, or if any part of the fracture ismore
45、than34 in. 19 mm from the center of a standard 2-in.50-mm gage length established by scribe scratches on theuntested specimen.S26. Homogenization Heat TreatmentS26.1 The homogenization heat treatment shall consist ofheating the castings and test material to a minimum of 1900F1040C, holding for a min
46、imum of 112 h, and cooling tobelow 90F 30C.S27. Product MarkingS27.1 The manufacturers name or identification mark andthe pattern number shall be cast or stamped on all castingsexcept those of such small size as to make such markingimpractical. To minimize small defects caused by dislodgedparticles
47、of molding sand, the number of cast identificationmarks should be minimized. When further specified, the heatnumbers shall be marked on individual castings.S27.2 When the castings are too small to mark individually,a symbol traceable to the lot shall be placed on the castings andthe required identif
48、ication then placed on a tag affixed to thecontainer in which these castings are shipped.SUMMARY OF CHANGESCommittee A01 has identified the location of selected changes to this standard since the last issue(A 747/A 747M 04) that may impact the use of this standard. (Approved June 1, 2007)(1) Revised
49、 Scope added new 1.4 and updated 1.5 to meetthe guidelines of A01 Form and Style Manual and A01Template for Developing Product Specifications.(2) Revised Referenced Documents added A 957/A 957Mfor investment castings and deleted A 732/A 732M, E 38, andE 353 that are covered by A 957/A 957M.(3) Revised General Conditions for Delivery to add therequirements for investment castings.(4) Revised and renumbered Ordering In
