1、Designation: A 27/A 27M 08Standard Specification forSteel Castings, Carbon, for General Application1This standard is issued under the fixed designation A 27/A 27M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last re
2、vision. 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. Scope*1.1 This specification covers carbon steel cast
3、ings for gen-eral applications that require up to 70 ksi (485 MPa) minimumtensile strength.NOTE 1The grades covered by this specification represent materialsthat are suitable for assembly with other steel castings or wrought steelparts by fusion welding. It is not intended to imply that all these gr
4、adespossess the same degree of weldability or that the same weldingtechniques can be used on all castings. It is the responsibility of thepurchaser to establish for himself a suitable welding technique.1.2 Several grades and two classes of steel castings arecovered, as indicated below. The grade and
5、 class desired shallbe specified by the purchaser.1.2.1 Grade N-1Chemical analysis only.1.2.2 Grade N-2Heat-treated but not mechanically tested.1.2.3 Grade U-60-30 415-205Mechanically tested butnot heat-treated.1.2.4 Grades 60-30 415-205, 65-35 450-240, 70-36485-250, and 70-40 485-275Heat-treated an
6、d mechani-cally tested.1.2.5 Class 1 and Class 2 steel castings shall be specified inaccordance with 9.2.1.3 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
7、 used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.2. Referenced Documents2.1 ASTM Standards:2A 370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA 732/A 732M Specification for Castings, Investment, Car-bon and
8、Low Alloy Steel for General Application, andCobalt Alloy for High Strength at Elevated TemperaturesA 781/A 781M Specification for Castings, Steel and Alloy,Common Requirements, for General Industrial UseA 957/A 957M Specification for Investment Castings, Steeland Alloy, Common Requirements, for Gene
9、ral IndustrialUse3. General Conditions for Delivery3.1 Except for steel investment castings, material furnishedto this specification shall conform to the requirements ofSpecification A 781/A 781M, including any supplementaryrequirements that are indicated in the purchase order. Failure tocomply with
10、 the general requirements of Specification A 781/A 781M constitutes nonconformance with the specification. Incase of a conflict between the requirements of this specificationand Specification A 781/A 781M, this specification shall pre-vail.3.2 Steel investment castings furnished to this specificatio
11、nshall conform to the requirements of Specification A 957/A 957M, including any supplementary requirements that areindicated in the purchase order. Failure to comply with thecommon requirements of Specification A 957/A 957M consti-tutes nonconformance with this specification. In case of con-flict be
12、tween the requirements of this specification and Speci-fication A 957/A 957M, Specification A 957/A 957M shallprevail.4. Ordering Information4.1 Orders for material under this specification shouldinclude the following information in proper sequence.4.1.1 Quantity,4.1.2 Specification, grade (1.2), an
13、d class (9.2),4.1.3 Description of the casting by pattern number ordrawing,4.1.4 Options in the specification, and4.1.5 Supplementary requirements desired, including stan-dards of acceptance.1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Allo
14、ys and is the direct responsibility of SubcommitteeA01.18 on Castings.Current edition approved Oct. 1, 2008. Published November 2008. Originallyapproved in 1901. Last previous edition approved in 2005 as A 27/A 27M 05.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact AS
15、TM Customer Service at 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 Consh
16、ohocken, PA 19428-2959, United States.5. Heat Treatment5.1 All castings of Grades N-2, 60-30 415-205, 65-35450-240, 70-36 485-250, and 70-40 485-275 shall beheat-treated by full annealing, normalizing, normalizing andtempering, or quenching and tempering. Unless otherwisespecified in the inquiry, co
17、ntract, or order, the castings may beheat-treated by any one or combination of these heat-treatments at the option of the manufacturer.5.1.1 Heat-treatment shall be performed after castings havebeen allowed to cool from the pouring temperature to belowthe transformation range.5.2 Furnace temperature
18、s for heat-treating shall be regulatedby the use of pyrometers.6. Chemical Composition6.1 The steel shall conform to the requirements as tochemical composition prescribed in Table 1. Product analysistolerances shall conform to the Product Analysis Tolerancesshown in Specification A 781/A 781M. When
19、residual elementchemical content is of interest to the purchaser, S54 may beconsidered.7. Tensile Properties7.1 Except for Grades N-1 and N-2, one tension test shall beperformed on each heat and the mechanical properties thusdetermined shall conform to the requirements specified inTable 2. The tensi
20、on test shall be performed in accordance withTest Methods and Definitions A 370.7.2 Test bars shall be poured in special blocks similar tothose shown in Fig. 1 of SpecificationA 781/A 781M and fromthe same heat as the casting represented.7.3 Test coupons may be cut from the heat-treated (ifrequired)
21、 castings or cast integrally with the castings at theproducers option.7.4 The test bars for heat-treated castings shall be heat-treated in production furnaces to the same procedure as thecastings they represent. When specified by the purchaser, thetest bars shall be heat-treated with the castings.7.
22、5 Test specimens shall be machined to the form anddimensions shown in Fig. 4 of Test Methods and DefinitionsA 370, with the ends machined to fit the grips on the tensiletesting machine to be used. Suggested types of ends forstandard round tension test specimens are shown in Fig. 5 ofTest Methods and
23、 Definitions A 370.7.6 If any specimen is machined improperly or if flaws arerevealed by machining or during testing, the specimen may bediscarded and another substituted from the same heat.7.7 When this specification is applied to investment cast-ings, test coupons and tension test specimens shall
24、be obtainedand prepared as directed in S3.2 of Specification A 732/A 732M. Test coupons shall be heat treated as prescribed in7.4.8. Retests8.1 If the results of the mechanical tests for any heat, lot, orcasting do not conform to the requirements specified, retestsare permitted as outlined in Test M
25、ethods and DefinitionsA 370. At the manufacturers option, castings may be reheat-treated and retested. When castings are reheat-treated, theymay not be reaustenitized more than 3 times without theapproval of the purchaser. Testing after reheat treatment shallconsist of the full number of specimens t
26、aken from locationscomplying with the specification or order.9. Rework and Retreatment9.1 All welds shall be inspected to the same quality stan-dards as were used to inspect the casting.9.2 If postweld heat-treatment is required, Class 1 must bespecified along with the grade, and the welds to be hea
27、t-treatedmust be defined. If postweld heat-treatment is not required,Class 2 must be specified along with the grade.10. Keywords10.1 castings; general application; steelTABLE 1 Chemical RequirementsGrade (UNS No.)AComposition, %Carbon,Bmax Manganese,Bmax Silicon, max Sulfur, max Phosphorus, maxGrade
28、 N-1 (J02500) 0.25 0.75 0.80 0.06 0.05Grade N-2 (J03500) 0.35 0.60 0.80 0.06 0.05Grade U-60-30 415-205 (J02500) 0.25 0.75 0.80 0.06 0.05Grade 60-30 415-205 (J03000) 0.30 0.60 0.80 0.06 0.05Grade 65-35 450-240 (J03001) 0.30 0.70 0.80 0.06 0.05Grade 70-36 485-250 (J03501) 0.35 0.70 0.80 0.06 0.05Grade
29、 70-40 485-275 (J02501) 0.25 1.20 0.80 0.06 0.05ASpecify Class 1 or Class 2 in addition to grade designation (see 9.2).BFor each reduction of 0.01 % carbon below the maximum specified, an increase of 0.04 % manganese above the maximum specified will be permitted to a maximumof 1.40 % for Grade 70-40
30、 485-275 and 1.00 % for the other grades.TABLE 2 Tensile RequirementsGradeATensileStrength,min,ksi (MPa)Yield Point,min, ksi(MPa)Elongation in2in.(50 mm),min, %BReduction ofArea,min, %Grade U-60-30(415-205)60 (415) 30 (205) 22 30Grade 60-30(415-205)60 (415) 30 (205) 24 35Grade 65-35(450-240)65 (450)
31、 35 (240) 24 35Grade 70-36(485-250)70 (485) 36 (250) 22 30Grade 70-40(485-275)C70 (485) 40 (275) 22 30ASpecify Class 1 or Class 2 in addition to grade designation (see 9.2).BWhen ICI test bars are used in tensile testing as provided for in thisspecification, the gage length to reduced section diamet
32、er ratio shall be 4 to 1.CGrade 70-40 485-275 may be used to meet the requirement of Grade 70-36485-250, when agreed upon between the manufacturer and the purchaser.A 27/A 27M 082SUPPLEMENTARY REQUIREMENTSAlist of standardized supplementary requirements for use at the option of the purchaser is desc
33、ribedin SpecificationA 781/A 781M. Those which are considered suitable for use with this specification arelisted below by title only. Additional supplementary requirements suitable for use with thisspecification at the option of the purchaser are described below. One or more of the supplementaryrequ
34、irements 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 body of the specification.Supplementary requirements details not fully described shall be agreed upon between the purchaserand the
35、 supplier, but shall not negate any of the requirements in the body of the specification.S1. Magnetic Particle ExaminationS2. Radiographic ExaminationS3. Liquid Penetrant ExaminationS4. Ultrasonic ExaminationS6. CertificationS8. MarkingS9. Charpy Impact TestS10. Hardness TestS12. Test ReportS13. Uns
36、pecified ElementsS14. Tension Test from CastingsS51. Permissible Variations in Dimensional Tolerances forCastings Made from Mounted PatternsS51.1 Tolerances for commercial steel castings (S51.1.1)made from mounted patterns and the surfaces that are not to bemachined shall be in accordance with Table
37、 3. Metal matchplate patterns and precise molding methods can produce closertolerances than the values shown in Table 3. Complex castingdesigns may require different permissible variations than thoselisted in Table 3.S51.1.1 The term “commercial castings” does not covercastings requiring special fix
38、tures for gaging, or finishingcastings by grinding to special tolerance gages beyond thenormal requirements as listed in Table 3.S52. Gate and Riser Projections for Castings Made fromMounted PatternsS52.1 Castings shall have gates and risers removed in sucha manner that no riser or gate stub project
39、s or a depression ismade beyond or below the casting design contour in an amountthat would exceed the values given in Table 4 .S53. Weight Deviation for Castings Made from MountedPatternsS53.1 The allowable deviations from the average castingweight are shown in Table 5 .S54. Chemical Analysis for Re
40、sidual ElementsS54.1 The manufacturer shall determine the percentage ofelements specified as follows, using procedures specified inSpecification A 781/A 781M. The chemical analysis thus de-termined shall conform to the following requirements:Copper, max, % 0.50Nickel, max, % 0.50Molybdenum, max, % 0
41、.25Chromium, max, % 0.50S54.2 Total content of these residual elements, maximumpercent 1.00.TABLE 3 Normally Expected Deviation of Linear CastingDimensions from Design DimensionsBlueprint Dimension, in. (mm) Tolerances, in. (mm)Up to 3 (75), incl +432 (3) 332 (2)Over 3 to 7 (75 to 175), incl +532 (4
42、) 432 (3)Over 7 to 20 (175 to 500), incl +632 (5) 532 (4)Over 20 to 100 (500 to 2500), incl +832 (6) 632 (5)TABLE 4 Gate and Riser Projection TolerancesRiser or Gate Maximum Di-mension, in. (mm)MaximumProjection,in. (mm)MaximumDepression,in. (mm)Up to 4 (100), incl18 (3)18 (3)Over 4 to 8 (100 to 200
43、), incl14 (6)18 (3)Over 8 to 20 (200 to 500), incl38 (10)18 (3)Over 20 to 30 (500 to 750), incl12 (13)14 (6)Over 30 (750)34 (19)14 (6)TABLE 5 Allowable DeviationAfrom Average Casting WeightCasting Weight, lb (kg) PositiveDeviation, %NegativeDeviation, %Up to 100 (45), incl 8.0 8.0Over 100 to 500 (45
44、 to 230), incl 6.5 5.0Over 500 to 10 000 (230 to 4540), incl 5.0 3.0Over 10 000 (4540) 3.0 2.5ADeviations do not apply to mass as calculated from a design drawing.A 27/A 27M 083SUMMARY OF CHANGESCommittee A01 has identified the location of selected changes to this standard since the last issue(A 27/
45、A 27M 05) that may impact the use of this standard. (Approved October 1, 2008.)(1) Add a new reference to paragraph 2.1.(2) Editorial changes to paragraph 3.1.(3) Add a new paragraph to Section 3.ASTM International takes no position respecting the validity of any patent rights asserted in connection
46、 with any item mentionedin this standard. Users of this standard are expressly advised 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 t
47、echnical 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 International Headquarters. Your comments will receive careful conside
48、ration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr
49、 Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).A 27/A 27M 084
