1、Designation: B686/B686M 11Standard Specification forAluminum Alloy Castings, High-Strength1This standard is issued under the fixed designation B686/B686M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last revision. A
2、 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 aluminum-alloy high-streng
3、thcastings designated as shown in Table 1.1.2 Castings covered by this specification are intended foruse in airframe, missile, and other critical applications wherehigh strength, ductility, and sound castings are required.1.3 Alloy and temper designations are in accordance withANSI H35.1/H35.1 (M).
4、The equivalent Unified NumberingSystem alloy designations are in accordance with PracticeE527.1.4 Unless the order specifies the “M” specification desig-nation, the material shall be furnished to the inch-pound units.1.5 For acceptance criteria for inclusion of new aluminumand aluminum alloys and th
5、eir properties in this specification,see Annex A1 and Annex A2.1.6 UnitsThe values stated in either SI units or inch-pound units are to be regarded separately as standard. Thevalues stated in each system may not be exact equivalents;therefore, each system shall be used independently of the other.Com
6、bining values from the two systems may result in non-conformance with the standard.1.7 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 safety and health practices and
7、determine the applica-bility of regular limitations prior to use.2. Referenced Documents2.1 The following documents of the issue in effect on thedate of purchase form a part of this specification to the extentreferenced herein:2.2 ASTM Standards:2B179 Specification for Aluminum Alloys in Ingot andMo
8、lten Forms for Castings from All Casting ProcessesB275 Practice for Codification of Certain Nonferrous Met-als and Alloys, Cast and WroughtB557 Test Methods for Tension Testing Wrought and CastAluminum- and Magnesium-Alloy ProductsB557M Test Methods for Tension Testing Wrought and CastAluminum- and
9、Magnesium-Alloy Products (Metric)B660 Practices for Packaging/Packing of Aluminum andMagnesium ProductsB881 Terminology Relating toAluminum- and Magnesium-Alloy ProductsB917/B917M Practice for Heat Treatment of Aluminum-Alloy Castings from All ProcessesD3951 Practice for Commercial PackagingE29 Prac
10、tice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE34 Test Methods for Chemical Analysis of Aluminum andAluminum-Base AlloysE94 Guide for Radiographic ExaminationE155 Reference Radiographs for Inspection of Aluminumand Magnesium CastingsE165 Practice for Liqui
11、d Penetrant Examination for GeneralIndustryE527 Practice for Numbering Metals and Alloys in theUnified Numbering System (UNS)E607 Test Method for Atomic Emission SpectrometricAnalysis Aluminum Alloys by the Point to Plane Tech-nique Nitrogen AtmosphereE716 Practices for Sampling and Sample Preparati
12、on ofAluminum and Aluminum Alloys for Determination ofChemical Composition by Spectrochemical AnalysisE1251 Test Method for Analysis of Aluminum and Alumi-num Alloys by Atomic Emission SpectrometryE2422 Digital Reference Images for Inspection of Alumi-num CastingsIEEE/ASTM SI 10 Standard for Use of
13、the InternationalSystem of Units (SI): The Modern Metric System2.3 AMS Standard:31This specification is under the jurisdiction of ASTM Committee B07 on LightMetals and Alloys and is the direct responsibility of Subcommittee B07.01 onAluminum Alloy Ingots and Castings.Current edition approved May 1,
14、2011. Published June 2011. Originallyapproved in 1981. Last previous edition approved in 2010 as B686/B686M 10.DOI: 10.1520/B0686_B0686M-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volum
15、e information, refer to the standards Document Summary page onthe ASTM website.3Available from Society of Automotive Engineers (SAE), 400 CommonwealthDr., Warrendale, PA 15096-0001, http:/www.sae.org.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100
16、 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.AMS 2771 Heat Treatment of Aluminum Alloy Castings2.4 ANSI Standards:4H35.1 / H35.1 (M) 2006 Alloy and Temper DesignationSystems for AluminumZ1.4 Sampling Procedures and Tables for Inspection byAttributes2.5 Military St
17、andard:5MIL-STD-129 Marking for Shipment and Storage2.6 Federal Standard:5Fed. Std. No. 123 Marking for Shipment (Civil Agencies)2.7 Other Standards:6CEN EN 14242 Aluminum and aluminum alloys . Chemicalanalysis. Inductively coupled plasma optical emissionspectral analysis3. Terminology3.1 Definition
18、s: Refer to Terminology B881 for definitionsof product terms used in this specification.4. Classification4.1 Castings shall be classified by inspection classes.4.1.1 Classes (Inspection):4.1.1.1 Class 1A class of casting, the single failure ofwhich would result in the loss of a missile, aircraft, or
19、 othervehicle.4.1.1.2 Class 2Class 1 castings not included in Class 1,the single failure of which would cause significant danger tooperating personnel or would result in a significant operationalpenalty. In the case of missiles, aircraft, and other vehicles, thisincludes loss of major components, lo
20、ss of control, uninten-tional release of inability to release armament stores, or failureof weapon installation components.4.1.1.3 Class 3Castings having a margin of safety of200 % or less.4.1.1.4 Class 4Castings having a margin of safety ofgreater than 200 %, or for which no stress analysis is requ
21、ired.All target drone castings and aerospace ground support equip-ment fall in this category, except for such critical parts, thefailure of which would make the equipment unsatisfactory andcause the vehicles which they are intended to support to beinoperable.4.1.2 Grades (Radiographic Quality):NOTE
22、1Caution should be exercised in specifying the grade ofmaximum permissible radiographic discontinuity level to be met in thecasting. Radiographic quality has only a qualitative relationship tomechanical properties. In general, the highest property levels of an alloywill require the higher grades of
23、radiographic quality. However, sectionsize and shape parameters may be able to tolerate certain discontinuitieswithout significant reduction in functional integrity. Too severe soundnessrequirements may cause the part producibility to be impractical oruneconomical.4.1.2.1 Grade AA grade in which the
24、re is no discerniblediscontinuity visible on the radiograph of the specified area ofthe casting.4.1.2.2 Grade BA premium grade of casting for criticalapplications or specified area of a casting with low margins ofsafety.4.1.2.3 Grade CA high-quality grade of casting or area ofa casting for general a
25、pplications.4.1.2.4 Grade DA grade included for less important areasof a casting.5. Ordering Information5.1 Orders for material under this specification shall includethe following information:5.1.1 This specification designation (which includes thenumber, the year, and the revision letter, if applic
26、able).NOTE 2For inch-pound application, specify Specification B686 and4Available from Aluminum Association, Inc., 1525 Wilson Blvd., Suite 600,Arlington, VA 22209, http:/www.aluminum.org.5Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia,
27、PA 19111-5098, http:/dodssp.daps.dla.mil.6Available from European Committee for Standardization (CEN), 36 rue deStassart, B-1050, Brussels, Belgium, http:/www.cenorm.be.TABLE 1 Chemical Composition LimitsNOTE 1When single units are shown, they indicate the maximum amounts permitted.NOTE 2Analysis sh
28、all be made for the elements for which limits are shown in this table.NOTE 3The following applies to all specified limits in this table: For purposes of determining conformance to these limits, an observed value or acalculated value obtained from analysis shall be rounded to the nearest unit in the
29、last right-hand place of figures used in expressing the specified limitin accordance with the rounding-off method of Practice E29.Composition, %ANSIH35.1ASTME527Former Silicon Iron CopperMan-ganeseMagne-siumZinc TitaniumOthersAluminumEachATotalBA201.0 A12010 0.05 0.10 4.05.0 0.200.40 0.150.35 0.150.
30、35C0.03 0.10 remainder354.0 A03540 SC92A 8.69.4 0.20 1.62.0 0.10 0.400.6 0.10 0.20 0.05 0.15 remainderC355.0 A33550 SC51B 4.55.5 0.20 1.01.5 0.10 0.400.6 0.10 0.20 0.05 0.15 remainderA356.0 A13560 SG70B 6.57.5 0.20 0.20 0.10 0.250.45 0.10 0.20 0.05 0.15 remainderA357.0 A13570 6.57.5 0.20 0.20 0.10 0
31、.400.7 0.10 0.040.20D0.05 0.15 remainderA“Others” includes listed elements for which no specific limit is shown as well as unlisted metallic elements. The producer may analyze samples for trace elements notspecified in the specification. However, such analysis is not required and may not cover all m
32、etallic “Others” elements. Should any analysis by the producer or the purchaserestablish that an “Others” element exceeds the limit of “Each” or that the aggregate of several “Others” elements exceeds the limit of “Total”, the material shall be considerednonconforming.BOther ElementsTotal shall be t
33、he sum of unspecified metallic elements 0.010 % or more, rounded to the second decimal before determining the sum.CSilver 0.40 to 1.0 %.DBeryllium 0.040.07.B686/B686M 112for metric application specify Specification B686M. Do not mix units.5.1.2 Alloy number (Section 7.1, Table 1) radiographicgrade (
34、4.1.2, Table 2) inspection class of castings (4.1.1, Table3 or Table 4) and class of mechanical properties (Table 5 orTable 6),5.1.3 Tensile property requirements on the drawing orpurchase order (9.1.5, 15.4, 15.5, Table 3 and Table 5 or Table4 and Table 6),5.1.4 Identification of product informatio
35、n (Section 11),5.1.5 Applicable drawings or part number,5.1.6 The quantity in either pieces or kilograms,5.2 Additionally, orders for material to this specificationshall include the following information when required by thepurchaser:5.2.1 Whether heat treatment is to be performed in accor-dance wit
36、h AMS 2771 (10.2),5.2.2 Where the preproduction samples shall be sent, andactivity responsible for testing, and instructions concerningsubmittal of the test reports (14.2.1 and 14.2.2),5.2.3 Penetrant inspection standards (15.2).5.2.4 Whether Practices B660 applies and, if so, the levelsof preservat
37、ion, packaging and packing required (16.3),5.2.5 Whether marking in accordance with Fed. Std. 123 orD3951 or MIL-STD-129 applies (16.3),5.2.6 Whether certification is required (17).6. Materials and Manufacture6.1 The responsibility of furnishing castings that can be laidout and machined to the finis
38、hed dimensions within thepermissible variations specified, as shown on the blueprints ordrawings, shall rest with the producer, except where patternequipment is furnished by the purchaser and any dimensionaldiscrepancies can be clearly attributed to the pattern equipmentas furnished.6.1.1 Unless oth
39、erwise specified, only aluminum alloy con-forming to the requirements of Specification B179 or produc-ers foundry scrap (identified as being made from alloyconforming to Specification B179) shall be used in the remelt-ing furnace from which molten metal is taken for pouringdirectly into castings. Ad
40、ditions of small amounts of modifiersand grain refining elements or alloys are permitted.6.1.2 Pure materials, recycled materials, and master alloysmay be used to make alloys conforming to this specification,provided chemical analysis can be taken and adjusted toconform to Table 1 prior to pouring a
41、ny castings.7. Chemical Composition and Sampling7.1 The product shall conform to the chemical compositionlimits prescribed in Table 1. Conformance shall be determinedby the producer by taking samples at the time castings arepoured in accordance with E716 and analyzed in accordancewith E607, E1251, E
42、34 or CEN EN 14242. If the producer hasTABLE 2 Discontinuity-Level Requirements for High-Strength Aluminum CastingsMaximum Permissible in Accordance with(Film Reference Radiographs E155 or Digital Reference Radiographs E2422)NOTE 1When two or more types of discontinuities are present withina2by2-in.
43、 50 mm by 50 mm area to an extent equal to or not significantlybetter than the acceptance standards for respective discontinuities, the castings shall be rejected.NOTE 2When two or more types of discontinuities are present within a 2 by 2-in. 50 mm by 50 mm area and the predominating discontinuity i
44、snot significantly better than the acceptance standard, the casting shall be considered borderline.NOTE 3Borderline castings shall be reviewed for acceptance or rejection by competent engineering personnel from the manufacturer and purchaser.NOTE 4Gas holes, sand spots, and inclusions allowed by thi
45、s table shall be cause for rejection when closer than twice their maximum dimension toan edge or extremity of a casting.NOTE 5Castings with the following characteristics apply to Alloy A201.1 only:1. Banding or striated segregation shall be acceptable to the extent that the mechanical properties in
46、the affected section meet the requirements ofTable 3.2. Healed hot tears or discrete segregation cracks, evidenced by linear irregular white lines, shall be rejected.3. Spheroidal segregation, evidenced by white spheroids, shall be evaluated for size and concentration by using the standards for gas
47、holes.Grade A Grade B Grade C Grade DDiscontinuity Radiograph Section Thickness, in.146 mm3419 mm146 mm3419 mm146 mm3419 mm146 mm3419 mmGas holes 1.1 none 1 1 2 2 5 5Gas porosity (round) 1.21 none 1 1 3 3 7 7Gas porosity (elongated) 1.22 none 1 1 3 4 5 5Shrinkage cavity 2.1 none 1A2A3AShrinkage poro
48、sity or sponge 2.2 none 1 1 2 2 4 3Foreign material (less densematerial)3.11 none 1 1 2 2 4 4Foreign material (more densematerial)3.12 none 1 1 2 1 4 3Segregation none none none noneCracks none none none noneCold shuts none none none noneLaps none none none noneSurface irregularity not to exceed dra
49、wing toleranceCore shift not to exceed drawing toleranceANot available. Use14 in.6 mm for all section thicknesses.B686/B686M 113determined the composition of the material during casting, theyshall not be required to sample and analyze the finishedproduct.7.2 If it becomes necessary to analyze castings for confor-mance to chemical composition limits, the method used tosample castings for the determination of chemical compositionshall be by agreement between the producer and the purchaser.Analysis s
