1、Designation: B918/B918M 17B918/B918M 17aStandard Practice forHeat Treatment of Wrought Aluminum Alloys1This standard is issued under the fixed designation B918/B918M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last
2、 revision. 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 U.S. Department of Defense.1. Scope Scope*1.1 This practice is intended for
3、 use in the heat treatment of wrought aluminum alloys for general purpose applications.1.1.1 The heat treatment of wrought aluminum alloys used in specific aerospace applications is covered in AMS 2772.21.1.2 Heat treatment of aluminum alloy castings for general purpose applications is covered in Pr
4、actice B917/B917M.1.2 Times and temperatures appearing in the heat-treatment tables are typical for various forms, sizes, and manufacturingmethods and may not provide the optimum heat treatment for a specific item.1.3 Some alloys in the 6xxx series may achieve the T4 temper by quenching from within
5、the solution temperature range duringor immediately following a hot working process, such as upon emerging from an extrusion die. Such alternatives to furnace heatingand immersion quenching are indicated in Table 2, by Footnote L, for heat treatment of wrought aluminum alloys. However, thispractice
6、does not cover the requirements for a controlled extrusion press or hot rolling mill solution heat treatment. (Refer toPractice B807 for extrusion press solution heat treatment of aluminum alloys and to Practice B947 for hot rolling mill solution heattreatment of aluminum alloys.)31.4 UnitsThe value
7、s stated in either SI units or inch-pound Metric or US Customary units are to be regarded separately asstandard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently ofthe other. Combining values from the two systems may result in non-conf
8、ormance with the standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prio
9、r to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barri
10、ers to Trade (TBT) Committee.2. Referenced Documents2.1 The following documents, of the issue in effect on the date of material purchase, form a part of this specification to the extentreferenced herein:2.2 ASTM Standards:3B557 Test Methods for Tension Testing Wrought and Cast Aluminum- and Magnesiu
11、m-Alloy ProductsB557M Test Methods for Tension Testing Wrought and Cast Aluminum- and Magnesium-Alloy Products (Metric)B881 Terminology Relating to Aluminum- and Magnesium-Alloy ProductsB917/B917M Practice for Heat Treatment of Aluminum-Alloy Castings from All ProcessesG69 Test Method for Measuremen
12、t of Corrosion Potentials of Aluminum Alloys2.3 American National Standard:H35.1/H35.1(M) Alloy and Temper Designation Systems for Aluminum41 This practice is under the jurisdiction ofASTM Committee B07 on Light Metals andAlloys and is the direct responsibility of Subcommittee B07.03 on AluminumAllo
13、yWrought Products.Current edition approved May 1, 2017Aug. 1, 2017. Published May 2017August 2017. Originally approved in 2001. Last previous edition approved in 20092017 asB918/B918M 09.B918/B918M 17. DOI: 10.1520/B0918_B0918M-17. 10.1520/B0918_B0918M-17A.2 Available from SAE International, 400 Com
14、monwealth Dr., Warrendale, PA 15096-0001, http:/www.sae.org.3 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.4
15、 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Bec
16、auseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appe
17、ars at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13. Terminology3.1 DefinitionsRefer to Terminology B881 for definitions of product terms used in this practice.3.2 Definition of Pyrometry Terms Specific to
18、 This Standard:3.2.1 control sensor, nsensor connected to the furnace temperature controller, which may or may not be recording.3.2.2 load sensor, nsensor that is attached to the production material or a representation of production material, that suppliestemperature data of the production material
19、to process instrumentation.3.2.3 monitoring sensor, nsensor connected to the monitoring instrument.3.2.4 test sensor, nsensor used in conjunction with a test instrument to perform a system accuracy test or temperatureuniformity survey.4. Equipment4.1 Heating MediaAluminum alloys are typically heat-t
20、reated in air chamber furnaces or molten salt baths; however, leadbaths, oil baths, or fluidized beds, may be used. The use of uncontrolled heating is not permitted. Whichever heating means areemployed, careful evaluation is required to ensure that the alloy being heat-treated responds properly to h
21、eat-treatment and is notdamaged by overheating or by the heat-treatment environment.4.1.1 Air chamber furnaces may be oil- or gas-fired or may be electrically heated. Furnace components that are significantlyhotter than the metal should be suitably shielded for metal less than 0.250 in. 6.35 mm thic
22、k to prevent adverse radiation effects.The atmosphere in air chamber furnaces must be controlled to prevent potential porosity resulting from solution heat treatment (seeNote 1). The suitability of the atmosphere in an air-chamber furnace can be demonstrated by testing, in accordance with 7.4.2.1,th
23、at products processed in that furnace are free from heat-treat induced porosity.NOTE 1Heat-treat induced porosity may lower mechanical properties and commonly causes blistering of the surface of the material. The conditionis most likely to occur in furnaces in which the products of combustion contac
24、t the work, particularly if the gases are high in water vapor or containcompounds of sulfur. In general, the high-strength wrought alloys of the 2xxx and 7xxx series are most susceptible. Low-strength and Alclad (two sides)products are practically immune to this type of damage. Anodic films and prop
25、rietary heat-treat coatings are also useful in protecting against porosityresulting from solution heat treatment. Surface discoloration is a normal result of solution heat treatment of aluminum alloys and should not be interpretedas evidence of damage from overheating or as heat-treat induced porosi
26、ty (see 7.4.2.1).4.1.2 Salt baths heat the work rapidly and uniformly. The temperature of the bath can be closely controlled, an importantconsideration in solution heat treatment of wrought aluminum alloys. High-temperature oxidation of aluminum is not a problemin salt baths.4.2 Furnace Temperature
27、Uniformity and Calibration Requirements:4.2.1 After establishment of thermal equilibrium or a recurrent temperature pattern, the temperature in the working (soaking)zone, for all furnace control and test sensors, shall maintain temperature in the working (soaking) zone within the followingallowable
28、ranges:4.2.1.1 50F 28C range for furnaces used only for full annealing at 825F 441C and higher, except 20F 12C range ifthe annealing temperature is within 15F 8C of the middle of the solution heat treating temperature range specified in Table 2.Annealing:(1) 50F 28C range for furnaces used only for
29、full annealing at 825F 441C and higher. Annealing temperatures shall becontrolled so as to preclude any material exceeding the lowest solution heat treating temperature for the alloy being annealed inaccordance with Table 2. In the case of a practice in accordance with Table 2 with only a specified
30、single solution heat treattemperature, the temperature shall not exceed the single provided temperature minus 10F/6C.(2) For furnaces used only for full annealing below 825F 441C and for stress relieving, there are no temperature uniformityrequirements.TABLE 1 Tests RequiredProduct Form Tensile Prop
31、ertiesA Heat-treat-inducedPorosityB Periodic TestIntergranular CorrosionCPeriodic TestDiffusion (Alclad Only)DPeriodic TestEutectic MeltingPeriodic TestPlate and sheet X X XE X XWire, rod, bar, and profiles X X X . . . XForgings X X X . . . XTubing X X . . . X XRivets, fastener components X X X . .
32、. XA Those specified in the applicable procurement material specification for lot release.B Applicable only to material solution heat-treated in air furnaces.CApplicable to the most quench-sensitive alloys-tempers in the following order of preference: (1 ) 2xxx in -T3 or -T4 and (2) 7xxx in -T6 temp
33、er. No test is required if 2xxx-T3or -T4 or 7xxx-T6, was not solution heat-treated during the period since the prior verification test.D Not applicable for thicknesses less than 0.020 in.E Applicable to periodic testing of sheet product only.B918/B918M 17a2TABLE 2 Recommended Heat Treatment for Wrou
34、ght Aluminum AlloysAProductSolution Heat Treatment Precipitation Heat TreatmentBMetal Temperature, 10F6CC,DQuench Temperature,F CE TemperMetal Temperature,10F 6CTime atTemperature, h Temper2011 AlloyACold-finished wire, rod, 945995 507535 110 43 max T3F 320 160 14 T8Fand bar T4 . . . . . . . . .T451
35、G . . . . . . . . . Drawn tube 975 524 110 43 max T3F 320 160 14 T8FT4511G . . . . . . . . .2014 AlloyAFlat sheet, bare 925945 496507 110 43 max T3F . . . . . . . . .or Alclad 935 502 T42 320 160 1820 T62 Coiled sheet, bare 925945 496507 110 43 max T4 320 160 18 T6or Alclad 935 502 T42 320 160 1820
36、T62 Plate, bare or Alclad 925945 496507 110 43 max T451G 320 160 18 T651G935 502 T42 350 177 89 T62 Cold-finished wire, rod, 925945 496507 110 43 max T4 350 177 9 T6and bar T451H 350 177 9 T651H935 502 T42 350 177 89 T62 Extruded wire, rod, bar, 925945 496507 110 43 max T4 350 177 9 T6profiles, and
37、tube T4510H 350 177 9 T6510HT4511H 350 177 9 T6511H935 502 T42 350 177 89 T62 Drawn tube 925945 496507 110 43 max T4 350 177 9 T6935 502 T42 350 177 89 T62 Die forgings 925945 496507 140180 6082 T4 350 177 9 T6 Hand forgings and rolled 925945 496507 140180 6082 T4 350 177 9 T6rings 935 502 T452I 350
38、 177 10 T652I2017 AlloyACold-finished wire, rod, 925950 496510 110 43 max T4 . . . . . . . . .and bar T451H . . . . . . . . .T42 . . . . . . . . .2018 AlloyADie forgings 940970 504521 212 100 T4 340 171 10 T612024 AlloyAFlat sheet, bare 910930 488499 110 43 max T3F 375 191 12 T81For Alclad 920 493 T
39、361J 375 191 8 T861JT42 375 191 910 T62T42 375 191 1618 T72 Coiled sheet, bare 910930 488499 110 43 max T4 375 191 910 T6or Alclad 920 493 T42 375 191 9 T62T42 375 191 1618 T72 Plate, bare or Alclad 910930 488499 110 43 max T351G 375 191 12 T851G920 493 T361J 375 191 8 T861JT42 375 191 910 T62 Cold-
40、finished wire, rod, 910930 488499 110 43 max T351H 375 191 12 T851Hand bar T36J . . . . . . . . .T4 375 191 12 T6920 493 T42 375 191 1213 T62 Extruded wire, rod, bar, 910930 488499 110 43 max T3F 375 191 12 T81Fprofiles, and tube T3510H 375 191 12 T8510HT3511H 375 191 12 T8511H920 493 T42 375 191 12
41、13 T62 Drawn tube 910930 488499 110 43 max T3F 375 191 12 T8F920 493 T42 375 191 910 T62 Die Forgings 910930 488499 110 43 max T3F 375 191 11 T81F2025 AlloyADie forgings 950970 510521 140160 6071 T4 350 177 9 T62117 AlloyACold-finished, wire 925950 496510 110 43 max T4 . . . . . . . . .or rodB918/B918M 17a3TABLE 2 ContinuedProductSolution
