1、Designation: B91 12B91 17Standard Specification forMagnesium-Alloy Magnesium-Alloy Forgings1This standard is issued under the fixed designation B91; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of last revision.Anumber
2、in parentheses indicates the year of last reapproval.Asuperscriptepsilon () 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*1.1 This specification covers magnesium alloy forgings design
3、ated as shown in Table 1.1.2 The values stated in inch-pound units are the standard. The SI values in parentheses are provided for information only.1.3 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on
4、Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 The following documents of the issue in effect on date of material purchase form a part of this specifica
5、tion to the extentreferenced herein:2.2 ASTM Standards:2B296 Practice for Temper Designations of Magnesium Alloys, Cast and WroughtB557 Test Methods for Tension Testing Wrought and Cast Aluminum- and Magnesium-Alloy ProductsB660 Practices for Packaging/Packing of Aluminum and Magnesium ProductsB666
6、Practice for Identification Marking of Aluminum and Magnesium ProductsB951 Practice for Codification of Unalloyed Magnesium and Magnesium-Alloys, Cast and WroughtB953 Practice for Sampling Magnesium and Magnesium Alloys for Spectrochemical AnalysisB954 Test Method for Analysis of Magnesium and Magne
7、sium Alloys by Atomic Emission SpectrometryE29 Practice for Using Significant Digits in Test Data to Determine Conformance with SpecificationsE55 Practice for Sampling Wrought Nonferrous Metals and Alloys for Determination of Chemical Composition2.3 Federal Standards:No. 123FED-STD-123H Marking for
8、Shipment (Civil Agencies)3No. 184 Identification Marking of Aluminum, Magnesium, and Titanium.2.4 Military Standards:MIL-STD-129 Marking for Shipment and Storage (Military Agencies)32.5 Aerospace Materials Specification:4AMS-M-3171 Magnesium Alloy, Processes for Pretreatment and Prevention of Corros
9、ion on3. Terminology3.1 Definitions:3.1.1 forginga metal part worked to a predetermined shape by one or more such processes as hammering, upsetting, pressing,or rolling.3.1.2 die forginga forging formed to the required shape and size by working in impression dies.3.1.3 hammer forginga forging produc
10、ed by repeated blows in a forging hammer.1 This specification is under the jurisdiction ofASTM Committee B07 on Light Metals andAlloys and is the direct responsibility of Subcommittee B07.04 on MagnesiumAlloy Cast and Wrought Products.Current edition approved Nov. 1, 2012May 1, 2017. Published Novem
11、ber 2012May 2017. Originally approved in 1932. Last previous edition approved in 20072012 asB91 07.B91 12. DOI: 10.1520/B0091-12.10.1520/B0091-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standards
12、volume information, refer to the standards Document Summary page on the ASTM website.3 Available from Standardization Documents Order Desk, DODSSP, Bldg. 4, Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http:/www.dodssp.daps.mil.4 Available from SAE International (SAE), 400 Commonwealth
13、Dr.,Warrendale, PA 15096-0001, http:/www.sae.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. Becauseit may not be technically possible to adequately depict all changes accurat
14、ely, 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 appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Dr
15、ive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.4 hand forginga forging worked between flat or simply shaped dies by repeated strokes or blows and manipulation of thepiece.4. Ordering Information4.1 Orders for forgings under this specification shall include the following inform
16、ation:4.1.1 Quantity of each forging,4.1.2 Alloy (Section 6 and Table 1),4.1.3 Temper (Section 7 and Table 2), ) in accordance with the requirements of Practice B296,4.1.4 Drawing showing dimensions of all die forgings and for all hand forgings not simple disks, rounds, squares, or rectangles(the am
17、ount of stock left for machine finish should be indicated),4.1.5 Surface treatment (see 9.1),4.1.6 Whether inspection is required at the manufacturers works (see 10.1),4.1.7 Special inspection requirements (see 10.2),4.1.8 Whether certification is required (see 12.1), andTABLE 1 Chemical Composition
18、 LimitsA,BNOTE 1Analysis shall regularly be made only for the elements specifically mentioned in this table. If, however, the presence of other elements issuspected or indicated in amounts greater than the specified limits, further analysis shall be made to determine that these elements are not pres
19、ent in excessof the specified limits.NOTE 2The following applies to all specified limits in this table. For purposes of acceptance and rejection, an observed value or a calculated valueobtained from analysis should be rounded to the nearest unit in the last right-hand place of figures used in expres
20、sing the specified limit.Composition, %ElementAlloy AZ31B(UNS No.M11311)Alloy AZ61A(UNS No.M11610)Alloy AZ80A(UNS No.M11800)Alloy ZK60A(UNS No.M16600)Magnesium remainder remainder remainder remainderAluminum 2.53.5 5.87.2 7.89.2 .Manganese 0.201.0 0.150.5 0.120.5 .Zinc 0.61.4 0.401.5 0.200.8 4.86.2T
21、horium . . . .Zirconium, min . . 0.45Silicon 0.10 0.10 0.10 .Copper 0.05 0.05 0.05 .Nickel 0.005 0.005 0.005 .Iron 0.005 0.005 0.005 .Calcium 0.04 . . .Other impuritiesC 0.30 0.30 0.30 0.30A Limits are in weight percent maximum unless shown as a range or stated otherwise.B These alloy designations w
22、ere established in accordance with Practice B951.C Includes listed elements for which no specific limit is shown.TABLE 2 Tensile RequirementsNOTE 1For purposes of determining conformance with thisspecification, each value for tensile strength and yield strength shall berounded to the nearest 0.1 ksi
23、 (0.7 MPa) and each value for elongationshall be rounded to the nearest 0.5 %, both in accordance with therounding method of Practice E29.Alloy andTemperTensileStrength,min, ksi(MPa)YieldStrengthA (0.2% offset),min, ksi(MPa)Elongationin 2 in.(51 mm), or4 dia,min, %AZ31BF 34.0 (234) 19.0 (131) 6AZ61A
24、F 38.0 (262) 22.0 (152) 6AZ80AF 42.0 (290) 26.0 (179) 5AZ80AT5 42.0 (290) 28.0 (193) 2ZK60AT5 die 42.0 (290) 26.0 (179) 7forgingsBZK60AT6 die 43.0 (296) 32.0 (221) 4forgingsBA See X1.1.6.B Applicable only to die forgings not more than 3 in. (76 mm) in thickness. Thetensile requirements for hand forg
25、ings will be lower and as agreed upon by thepurchaser and manufacturer.B91 1724.1.9 Whether marking for identification is required (see 13.1).5. Quality Assurance5.1 The manufacturer shall be responsible for the performance of all inspection and tests required by this specification, priorto shipment
26、 of the material.6. Chemical Composition6.1 LimitsThe material shall conform to the chemical composition limits prescribed in Table 1. The manufacturer shalldetermine conformance by analyzing samples taken when the ingots are poured, or by analyzing samples taken from the finishedor semi-finished pr
27、oduct. If the manufacturer has determined the chemical composition during the course of manufacture, he shallnot be required to sample and analyze the finished product.6.2 Number of SamplesThe number of samples taken for determination of chemical composition shall be as follows:6.2.1 When samples ar
28、e taken at the time the ingots are poured, at least one sample shall be taken for each group of ingotspoured simultaneously from the same source of molten metal.6.2.2 When samples are taken from the finished or semi-finished product, a sample shall be taken to represent each 2000 lb (905kg), or frac
29、tion thereof, in the shipment, except that not more than one sample shall be required per piece.6.3 Methods of SamplingSamples for determination of chemical composition shall be taken in accordance with one of thefollowing methods:6.3.1 Samples for chemical analysis shall be taken from the material
30、by drilling, sawing, milling, turning, or clipping arepresentative piece or pieces to obtain a weight of prepared sample not less than 75 g. Sampling shall be in accordance withPractice E55.6.3.2 Samples for spectrochemical analysis shall be in accordance with Practice B953, or other methods of anal
31、ysis shall betaken by methods suitable for the form of material being analyzed and the type of analytical method used.6.4 Methods of Chemical AnalysisAny suitable method of chemical analysis may be used. In case of dispute, the analysis shallbe made by methods given in Test Method B954 or any other
32、standard methods of analysis approved byASTM unless some othermethod is agreed upon.7. Tensile Properties7.1 LimitsThe forgings shall conform to the tensile properties prescribed in Table 2.7.2 Number of SpecimensOne tension test specimen shall be taken to represent each 1000 lb (455 kg) or fraction
33、 thereof ofeach part number in the shipment or inspection lot.7.2.1 When specified, a grain flow pattern and tensile-property survey shall be made on a forging representative of the firstproduction parts (see 7.3.1). It shall be repeated after any major change in forging technique.7.3 Test Specimens
34、Tension test specimens shall be taken from a forging or from a separately forged coupon made frommaterial representative of the forgings, in such a manner that the longitudinal axis of the specimen is parallel to the direction ofmaximum flow of the metal in the forging. The specimens shall be machin
35、ed to the form and dimensions shown in Fig. 8 of TestMethods B557 or in the case of thin material may be machined to the form and dimensions shown for the 12 in. (12.7 mm) widesheet-type specimen in Fig. 6 of Test Methods B557.7.3.1 If required, a die forging representative of the first production p
36、arts shall be selected after forging techniques have beenestablished, and shall be tested as follows:7.3.1.1 Tension test specimens shall be taken parallel to the forging flow lines. The locations shall be as indicated on the forgingengineering drawing or, if not indicated, from generally representa
37、tive areas.7.3.1.2 A sample forging shall be sectioned at the locations of the specimens, to show the grain flow.7.3.2 For hand forgings, the specimens shall be taken from a prolongation of the forgings or from a forging chosen to representthe lot. Tests will regularly be made only in the longitudin
38、al direction.7.4 Test MethodsThe tension tests shall be made in accordance with Test Methods B557.NOTE 1The values obtained for the tensile properties covered by this specification are not seriously affected by variations in speed of testing. Aconsiderable range of testing speed is permissible; howe
39、ver, the rate of stressing to the yield strength should not exceed 100 ksi (690 MPa)/min, and abovethe yield strength the movement per minute of the head under load should not exceed 0.5 in./in. (mm/mm) of gage length. Care must be exercised,especially when making yield strength determinations, that
40、 the speed of testing does not exceed the ability of the strain- and load-indicating equipmentto function satisfactorily.7.5 RetestsIf any test specimen fails to conform to the requirements of Table 2, two additional representative specimens shallbe selected and tested. If either of these specimens
41、fails to conform to the requirements, the lot may be rejected. If, however, itis suspected that specimen failure is due to inadequate thermal treatment, the material may be reheat-treated and resampled inaccordance with 7.2. Only one such reheat treatment shall be permitted.B91 1738. General Quality
42、8.1 All material shall be of uniform quality, free of injurious surface defects, and shall have a workmanlike finish.9. Finish9.1 Unless otherwise specified, the forgings shall be chrome pickled prior to shipment (see X1.1.7).10. Inspection10.1 If the purchaser desires that inspection be made at the
43、 manufacturers works where the material is made, it shall be so statedin the contract or purchase order.10.1.1 If the purchaser elects to have the inspection made at the manufacturers works, the manufacturer shall afford theinspector representing the purchaser all reasonable facilities to satisfy hi
44、m that the material is being furnished in accordance withthis specification. All tests and inspection shall be so conducted as not to interfere unnecessarily with the operation of the works.10.2 Special inspection requirements such as inspection by ultrasonic reflection or by fluorescent penetrant,
45、must be shown onthe order. Acceptance standards for special inspection requirements shall be as agreed upon between purchaser and manufacturer.11. Rejection11.1 Material failing to conform to the requirements of this specification, or in which defects are found during subsequentmanufacturing operati
46、ons, may be rejected. If rejected, the manufacturer shall be responsible only for replacement of the materialto the purchaser. All of the rejected original material shall be returned to the manufacturer.12. Certification12.1 The supplier shall, on request, furnish to the purchaser, a certificate sta
47、ting that the material has been sampled, tested, andinspected in accordance with this specification, and has met the requirements.13. Product Marking13.1 The material shall be marked as specified in the purchase order.order and in accordance with the requirements of PracticeB66613.2 Each package or
48、container shall be marked with the purchase order number, drawing number, quantity, specificationnumber, alloy and temper, gross and net weights, and the name of the manufacturer.14. Packaging14.1 The material shall be packaged in such a manner as to prevent damage in ordinary handling and transport
49、ation. The typeof packing and gross weight of individual containers shall be left to the discretion of the manufacturer unless otherwise agreedupon. Packaging methods and containers shall be so selected as to permit maximum utility of mechanical equipment in unloadingand subsequent handling. Each package or container shall contain only one size, alloy, and temper of material when packaged forshipment unless otherwise agreed upon.14.2 Packages or containers shall be such as to ensure acceptance by common or other carriers for safe transp
