1、Designation: A 159 83 (Reapproved 2006)Standard Specification forAutomotive Gray Iron Castings1This standard is issued under the fixed designation A 159; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、number in parentheses indicates the year of last reapproval. Asuperscript 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. This specification replaces Federal specificationAA-I-653A.1. Sc
3、ope1.1 This specification applies to gray iron castings, cast insand molds, used in the products of the automobile, truck,tractor, and allied industries.1.2 The values stated in inch-pound units are to be regardedas the standard.2. Referenced Documents2.1 The following documents of the issue in effe
4、ct on thedate of material procurement form a part of this specification tothe extent referenced herein:2.2 ASTM Standards:2A 247 Test Method for Evaluating the Microstructure ofGraphite in Iron CastingsE10 Test Method for Brinell Hardness of Metallic Materi-als2.3 Military Standard:MIL-STD-129 Marki
5、ng for Shipment and Storage32.4 Federal Standard:Fed. Std. No. 123 Marking for Shipment (Civil Agencies)33. Grades3.1 The specified grades, hardness ranges, and metallurgicaldescription are shown in Table 1 and Table 2 and in Section 9.4. Ordering Information4.1 Orders for materials under this speci
6、fication shall in-clude the following information:4.1.1 ASTM designation,4.1.2 Grade designation of gray iron required (3.1),4.1.3 If special heat treatment is required (see Section 6),4.1.4 If special microstructure requirements are needed (seeSection 7),4.1.5 Surface where hardness test is to be p
7、erformed (see9.4),4.1.6 Depth and surface hardness of case required (see 9.6),4.1.7 Inspection lot and sampling plan required (see Section10),4.1.8 If additional requirements are needed (see 11.3), and4.1.9 Whether special packaging and marking is required(see Section 12).5. Hardness5.1 The foundry
8、shall exercise the necessary controls andinspection techniques to ensure compliance with the specifiedhardness range, Brinell hardness shall be determined in accor-dance with Test Method E10, after sufficient material has beenremoved from the casting surface to ensure representativehardness readings
9、. The 10-mm ball and 3000-kg load shall beused unless otherwise agreed upon. The area or areas on thecasting where hardness is to be checked shall be established byagreement between supplier and purchaser and shall be shownon the drawing.6. Heat Treatment6.1 Unless otherwise specified, castings of G
10、rades G1800and G2500 may be annealed in order to meet the desiredhardness range.1This specification is under the jurisdiction of ASTM Committee A04 on IronCastings and is the direct responsibility of SubcommitteeA04.01 on Gray and WhiteIron Castings.Current edition approved Oct. 1, 2006. Published O
11、ctober 2006. Originallyapproved in 1935. Last previous edition approved in 2001 as A 159 83 (2001).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Doc
12、ument Summary page onthe ASTM website.3Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http:/www.dodssp.daps.mil.TABLE 1 Grades of Gray IronGrade Casting Hardness Range DescriptionG1800 HB 187 max4.4 BID min or as agreedA
13、ferritic-pearliticG2500 HB 170-2294.64.0 BID or as agreedApearlitic-ferriticG3000 HB 187-2414.43.9 BID or as agreedApearliticG3500 HB 207-2554.23.8 BID or as agreedApearliticG4000 HB 217-2694.13.7 BID or as agreedApearliticABrinell impression diameter (BID) is the diameter in millimetres of the impr
14、es-sion of a 10 mm ball at 3000-kg load.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.2 Appropriate heat treatment for removal of residualstresses, or to improve machinability or wear resistance may bespecified by agreement betwe
15、en supplier and purchaser.7. Microstructure7.1 The microstructure shall consist of flake graphite in amatrix of ferrite or pearlite or mixtures thereof.7.2 As graphite size and shape somewhat affect hardness-strength ratio and other properties, the type size and distribu-tion of the graphite flakes
16、at a designated location on thecasting may be specified by agreement between supplier andpurchaser in accordance with Method A 247.7.3 Unless otherwise specified, the matrix microstructure ofcastings covered by this specification shall be substantially freeof primary cementite. Castings in Grades G1
17、800 and G2500may have a matrix of ferrite or pearlite or both. Grades G3000,G3500, and G4000 shall be substantially pearlite in matrixstructure.8. Heavy-Duty Brake Drums and Clutch Plates8.1 These castings are considered as special cases and arecovered in Table 2.9. Alloy Gray Iron Automotive Camsha
18、fts9.1 These castings are considered as special cases.9.2 Grade DesignationG4000d.9.3 ChemistryAlloy gray iron camshafts shall containalloys within the following range or as agreed upon betweensupplier and purchaser.Chromium 0.851.25 %Molybdenum 0.400.60 %Nickel as agreed9.4 Casting HardnessHB 241-3
19、21 determined on a bear-ing surface as agreed by supplier and purchaser.9.5 MicrostructureExtending 45 on both sides of thecenterline of the cam nose and to a minimum depth of 1/8 in.(3.2 mm), the surface shall consist of primary carbides (ofacicular or cellular form or a mixture thereof) and graphi
20、te ina fine pearlitic matrix. The graphite shall be Type VII A and Edistribution, 4 to 7 flake size in accordance with MethodA 247.The amount of primary carbides and location at which thestructure is checked shall be a matter of agreement between thesupplier and the purchaser.9.6 Selective Hardening
21、The cam areas of camshaft cast-ing are usually selectively hardened by flame or inductionhardening by the supplier. The depth and surface hardness ofthe hardened case shall be as agreed upon between supplier andpurchaser.10. Quality Assurance Provisions10.1 Responsibility for InspectionUnless otherw
22、ise speci-fied in the contract or purchase order, the producer is respon-sible for the performance of all inspection and tests require-ments specified in this specification. Except as otherwisespecified in the contract or purchase order, the producer mayuse his own or any other suitable facilities f
23、or the performanceof the inspection and test requirements specified herein, unlessdisapproved by the purchaser. The purchaser shall have theright to perform any of the inspection and tests set for in thisspecification where such inspections are deemed necessary toassure that material conform to pres
24、cribed requirements.10.2 LotFor the purpose of inspection, lot and samplingplans shall be agreed upon between the purchaser and theproducer.11. General11.1 Castings furnished to this specification shall be repre-sentative of good foundry practice and shall conform todimensions and tolerances specifi
25、ed on the casting drawing.11.2 Minor imperfections usually not associated with thestructural function may occur in castings. These are oftenrepairable but repairs shall be made only where allowed by thepurchaser and only by approved methods.11.3 Additional casting requirements may be agreed uponby p
26、urchaser and supplier. These should appear as productspecifications on the casting or part drawing.12. Preparation for Delivery12.1 Unless otherwise specified in the contract or purchaseorder, castings shall be cleaned, preserved, and packaged inaccordance with suppliers standard commercial practice
27、.12.2 Government ProcurementWhen specified for Gov-ernment procurement, castings shall be marked for shipment inaccordance with MIL-STD-129 for military procurement andFed. Std. No. 123 for civil agency procurement.TABLE 2 Brake Drums and Clutch Plates for Special ServiceGrade Carbon min, %ACasting
28、HardnessMicrostructureGraphite MatrixG2500a 3.40 HB 170-2294.64.0 BID or as agreedType VII, size 24BA distributionlamellar pearliteferrite if present not to exceed 15%G3500b 3.40CHB 207-2554.23.8 BID or as agreedType VII, size 35BA distributionlamellar pearliteferrite or carbide if present not to ex
29、ceed 5%G3500c 3.50CHB 207-2554.23.8 BID or as agreedType VII, size 35BA distributionlamellar pearliteferrite or carbide, if present not to exceed 5%AThe chemical analysis for total carbon shall be made on chilled pencil-type specimens or from thin wafers approximately 1/32 in. (0.8 mm) thick cut fro
30、m test coupons.Drillings are not reliable because of the probable loss of graphite.BSee Method A 247.CGrades G 3500b and G 3500c normally require alloying to obtain the specified hardness at the high carbon levels specified.A 159 83 (2006)2APPENDIX(Nonmandatory Information)X1. GRAY IRONX1.1 Definiti
31、onX1.1.1 gray irona cast iron in which the graphite ispresent as flakes instead of temper carbon nodules as inmalleable iron or small spherulites as in ductile iron.X1.2 Chemical CompositionX1.2.1 The ranges in composition generally employed inproducing the various grades of most automotive gray iro
32、ncastings are shown in Table X1.1. The composition ranges forsuch special applications as heavy duty brake drums and clutchplates and camshafts are shown in Table X1.2 and Table X1.3,respectively. The contents of certain elements for these appli-cations are critical in terms of service requirements
33、and theranges are specified in the standard.X1.2.2 The specific composition range for a given grademay vary according to the prevailing or governing section ofthe castings being produced.X1.2.3 Alloying elements such as chromium, copper,nickel, tin, molybdenum, or other elements may be employedto me
34、et the specified hardness or microstructural requirementsor to provide the properties needed for particular serviceconditions.X1.3 MicrostructureX1.3.1 The microstructure of the various grades of gray ironare generally a mixture of flake graphite in a matrix of ferrite,pearlite, or tempered pearlite
35、. The relative amounts of each ofthese constituents depends on the analysis of the iron, castingdesign, and foundry techniques as they affect solidification andsubsequent cooling rate and heat treatments if any.X1.3.2 The distribution and size of graphite flakes like thematrix structure of gray iron
36、 depends greatly on the solidifi-cation rate and cooling rate of the casting. If a section solidifiesvery rapidly an appreciable amount of carbide causing amottled fracture or chilled corners can be present. If a sectioncools slowly, as in a massive heavy-section casting, an appre-ciable amount of f
37、errite may be present. In like manner, lightsections will contain small graphite flakes while graphite willform in much larger flakes if the same iron is poured into aheavy casting.X1.3.3 For these reasons the strength and hardness of grayiron are greatly influenced by the rate of cooling during and
38、after solidification, the design and nature of the mold and thecasting, and by other factors such as inoculation practice inaddition to the composition of the iron.X1.3.4 Alloying with nickel, chromium, molybdenum, tin,copper or other alloys usually promotes a more stable pearliticstructure and is o
39、ften done to obtain increased hardness,strength, and wear resistance especially in heavy sectionssubjected to severe service.X1.3.5 Alloying is sometimes used to obtain structurescontaining a controlled percentage of carbides as in camshaftor valve lifter castings.X1.3.6 Primary carbides or pearlite
40、 or both, can be decom-posed by appropriate heat treatment. Gray irons of suitableTABLE X1.1 Typical Base Compositions, %Grade Carbon Silicon Manganese Sulfur, max Phosphorus, max Approximate CarbonEquivalentG1800 3.403.70 2.302.80 0.500.80 0.15 0.25 4.254.5G2500 3.203.50 2.002.40 0.600.90 0.15 0.20
41、 4.04.25G3000 3.103.40 1.902.30 0.600.90 0.15 0.15 3.94.15G3500 3.003.30 1.802.20 0.600.90 0.15 0.12 3.73.9G4000 3.003.30 1.802.10 0.701.00 0.15 0.10 3.73.9(usually alloyed)TABLE X1.2 Usual Composition of Brake Drums and ClutchPlates for Special ServiceChemical Compo-sition, %GradeG2500aGradeG3500bG
42、radeG3500cCarbon, total (mandatory) 3.40 min 3.40 min 3.50 minSilicon (as required) 1.602.10 1.301.80 1.301.80Manganese (as required) 0.600.90 0.600.90 0.600.90Sulfur, max 0.12 0.12 0.12Phosphorus, max 0.15 0.15 0.15Alloys as required as required as requiredTABLE X1.3 Usual Chemical Composition of A
43、lloy Gray IronAutomotive CamshaftsGrade G4000d, %Total carbon 3.103.60Silicon 1.952.40Manganese 0.600.90Phosphorus 0.10 maxSulfur 0.15 maxChromium 0.851.25Molybdenum 0.400.60Nickel 0.200.45 optionalCopper residualA 159 83 (2006)3composition and structure can be hardened by liquid quenchingor by flam
44、e or induction selective hardening.X1.4 Mechanical PropertiesX1.4.1 The mechanical properties listed in Table X1.4 canbe used for design purposes. However, the suitability of aparticular grade for an intended application is best determinedby laboratory or service tests. Typical mechanical properties
45、for such specialized applications as heavy-duty brake drumsand clutch plates are shown in Table X1.5.X1.5 Application of Gray Iron in Automotive Castings(see Table X1.6)X1.5.1 The graphite flakes in gray iron give this metal manydesirable properties. These include excellent machinability,high therma
46、l conductivity, vibration dampening properties, andresistance to wear or scuffing. Due to its low freezing tempera-ture for a ferrous alloy, high fluidity, and low shrinkageproperties it is more readily cast in complex shapes than otherferrous metals.X1.5.2 Gray iron castings of the lower-strength G
47、radesG1800 and G2500 are characterized by excellent machinabil-ity, high damping capacity, low modulus of elasticity, andcomparative ease of manufacture. When higher strength isobtained by a reduction in the carbon or carbon equivalent,castings are more difficult to machine, have lower dampingcapaci
48、ty, higher modulus of elasticity, and may be moredifficult to manufacture.X1.6 Special Applications of Gray IronX1.6.1 Heavy-Duty Brake Drums and Clutch PlatesAutomotive brake drums and clutch plates for heavy-dutyservice are considered as special cases. Typical chemicalanalyses and mechanical prope
49、rties are listed in Table X1.2 andTable X1.5. Heavy-duty irons for such service require highcarbon contents for resistance to thermal shock and to mini-mize heat checking. To maintain strength levels specified forGrades G3500b and G3500c normally requires alloying due totheir high carbon contents.X1.6.2 MicrostructureSee Table 2 for microstructure requirements.X1.6.3 Suggested UsageFollowing are suggested grades for brake drums and clutchplates according to types of service:Grade Suggested UsageG2500a Brake drums and clutch pl
