1、Designation: B 777 07Standard Specification forTungsten Base, High-Density Metal1This standard is issued under the fixed designation B 777; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in pare
2、ntheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers the requirements for fourclasses of machinable, high-density tungsten base metal pro-duced by consolidating metal powder m
3、ixtures, the composi-tion of which is mainly tungsten. This material specificationmay be used for bare parts or for parts that may be coated withother materials for protection against corrosion and abrasion.1.2 Intended UseParts made from this material are in-tended for uses such as weights or count
4、er-balances in static ordynamic balancing, high-speed rotating inertia members, ra-diation shielding, hypervelocity impact, and vibration-dampingapplications.1.3 Special ApplicationsFor particular applications, prop-erties or requirements other than those specified in Sections 5,6, and 7 of this spe
5、cification may be important. These alloysmay contain elements which make them magnetic. Wherefreedom from magnetic response is required, this should bespecified in the purchase order. Class 4 is not available in anon-magnetic grade. For purposes of this specification, non-magnetic material is define
6、d as material having a maximummagnetic permeability of 1.05 (see Test Method B 193). Alsofor special applications involving large sections, methods fordetermining internal quality, such as mechanical tests onspecimens from these larger sections or suitable nondestructivetests may be applied. If requ
7、ired, these additional tests shall bespecified in the purchase order.1.4 The values stated in inch-pound units are to be regardedas the standard. The values given in parentheses are forinformation only.2. Referenced Documents2.1 ASTM Standards:2A 600 Specification for Tool Steel High SpeedB 193 Test
8、 Method for Resistivity of Electrical ConductorMaterialsB311 Test Method for Density Determination for PowderMetallurgy (P/M) Materials Containing Less Than TwoPercent PorosityD 3951 Practice for Commercial PackagingE3 Guide for Preparation of Metallographic SpecimensE8 Test Methods for Tension Test
9、ing of Metallic MaterialsE18 Test Methods for Rockwell Hardness of MetallicMaterialsE 407 Practice for Microetching Metals and Alloys2.2 Federal Standard:Fed. Std. No. 151 Metals, Test Methods33. Classification3.1 The tungsten base metal shall be of the following classes(see Table 1 and Table 2), as
10、 specified (see 4.1):Class Tungsten, Nominal Wt.%1902 92.53954974. Ordering Information4.1 Orders for tungsten base, high-density metal shouldspecify the following:4.1.1 Title, designation, and year of issue of this specifica-tion,4.1.2 Class, (see 3.1),4.1.3 Machinability requirements, if any (see
11、7.3),4.1.4 Quantity,4.1.5 Levels of preservation and packing (see 9.1),4.1.6 Special markings, if required (see 9.2),4.1.7 Method of hardness testing, if different from Rockwell“ C” (see Table 1),4.1.8 Freedom of parts from magnetic response, if required(see 1.3), and4.1.9 Dimensions and tolerances.
12、5. Materials and Manufacture5.1 MaterialsThe raw materials shall be a mixture ofloose metal powders consisting mainly of tungsten and a1This specification is under the jurisdiction of ASTM Committee B10 onReactive and Refractory Metals and Alloys and is the direct responsibility ofSubcommittee B10.0
13、4 on Molybdenum and Tungsten.Current edition approved Nov. 1, 2007. Published November 2007. Originallyapproved in 1987. Last previous edition approved in 1999 as B 777 - 99.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For
14、Annual Book of ASTMStandards volume information, refer to the standards Document 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.1Copyright ASTM International, 10
15、0 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.metallic powder binder such as copper, nickel or iron, which,by sintering, will produce materials meeting the requirementsof this specification.6. Chemical Composition6.1 The specified class shall have the nominal tung
16、stencontent in Table 1.7. Physical and Mechanical Properties7.1 Composition, Physical and Mechanical PropertiesThe sintered material shall have properties conforming to Table1 and Table 2 as determined on standard sintered test bars (seeTest Methods E8).7.2 MicrostructureThe microstructure of each s
17、ampleshall be a uniform distribution of tungsten particles in a bindermetal matrix when viewed at a magnification of 200 times. Thelocation may be specified (see 8.4.5).7.3 MachinabilityWhen specified (see 4.1), the machin-ability of the basic parts or of a suitable test specimen shall besuch that i
18、t shall pass the test specified in 8.4.6.7.4 IdentificationEach lot and associated test bars shall beclearly marked with a lot serial number (see 8.3.1).8. Quality Assurance Provisions8.1 Responsibility for InspectionUnless otherwise speci-fied in the contract or purchase order, the manufacturer isr
19、esponsible for the performance of all inspection requirementsas specified herein. Except as otherwise specified in thecontract or purchase order, the manufacturer may use his ownfacilities for the performance of the inspection or any otherfacility that is acceptable to the purchaser.8.2 Responsibili
20、ty for ComplianceAll parts must meet allthe requirements agreed upon by purchaser and manufacturerfrom Sections 4, 6 and 7. The inspections set forth in thisspecification shall become a part of the manufacturers overallinspection system or quality program.8.3 Quality Conformance Inspection:8.3.1 Ins
21、pection LotAn inspection lot shall consist of auniform blend from one batch of powder, and submitted forinspection at one time. If a shipment is made from more thanone lot, the purchaser may choose to consider that shipment asa single inspection lot or may choose to separate the shipmentinto several
22、 inspection lots for acceptance purposes.8.3.2 SamplingUnless otherwise specified, a minimum oftwo sintered test bars and one chemical analysis sample shallbe made from each powder lot.8.3.3 Hardness TestsEach test bar shall be tested forconformance with the hardness requirements of Table 1 (see8.4.
23、1).8.3.4 DensityEach test bar shall be tested for conform-ance with the density requirements of Table 1 (see 8.4.2).8.3.5 Tension TestsEach test bar shall be tested for con-formance with Table 2 (see 8.4.3).8.3.6 Chemical CompositionIf specified in the purchaseorder, a chemical analysis sample from
24、each lot shall be testedfor the tungsten content in conformance with Table 1 (see8.4.4).8.3.7 Examination of MicrostructureThis test shall beaccomplished on one of the test bars (see 8.4.5).8.4 Methods for Test and Examinations:8.4.1 HardnessSamples shall be tested in accordance withTest Methods E18
25、.8.4.2 DensityThe equal water displacement method per-formed in accordance with Test Method B311shall be used.8.4.3 Mechanical PropertiesSamples shall be tested inaccordance with Test Methods E8.8.4.4 Chemical AnalysisAnalysis of the lot or lots inquestion shall be made by Method 111 or 112 of Fed.
26、Std. No.151 for conformance with 8.3.6. In case of dispute, chemicalanalysis by Method 111 shall be the basis for acceptance.8.4.5 MicrostructureA test bar shall be sectioned and aspecimen shall be prepared for examination in accordance withGuide E3. The specimen may be etched (see Practice E 407),a
27、nd shall be examined at a magnification of 200 times forconformance with 7.2.8.4.6 MachinabilityIf specified by the procuring docu-ment, this test shall be made on a representative sample. Holes,0.1695 in. in diameter and a minimum of 0.343 in. deep shallbe drilled and tapped with a No. 10-32 high-s
28、peed steel tap toa minimum full thread of 0.312 in. deep. The tap shall be ofhigh speed steel, conforming to Specification A 600, Type M1,heat treated to a hardness of 62-63 HRC. Machinability will beconsidered acceptable in each class if each of the number ofholes indicated in Table 3 is satisfacto
29、rily threaded to aminimum 60 % without destruction of the tap.TABLE 1 Composition, Density and Hardness PropertiesClassNominalTungsten,weight %Density,g/ccHardnessA,BRockwell “C,”max1 90 16.8517.25 322 92.5 17.1517.85 333 95 17.7518.35 344 97 18.2518.85 35AWhen specified by the purchaser, other hard
30、ness testing methods may beemployed.BFor mechanically worked or aged material, the hardness can be as high asRc46.TABLE 2 Mechanical Properties, Minimum ValuesClassUltimate TensileStrengthYield Strengthat 0.2 % Off-setElongation,A%ksi MPa ksi MPa1110B758 75 517 5B21B758 75 517 5B3 105B724 75 517 3B4
31、 100 689 75 517 2ADetermine with an extensometer accurate to 0.5 % elongation or less.BNonmagnetic composition to Classes 1, 2 and 3 shall be 94 ksi (648 MPa)minimum ultimate tensile strength. Minimum elongation shall be 2 % on Classes 1and 2 and 1 % on Class 3.TABLE 3 Machinability RequirementsClas
32、s Number of Holes18263442B7770728.5 RejectionUnless otherwise stated in the purchaseorder, failure to conform to any of the requirements of thisspecification shall be cause for rejection of the lot.9. Packaging and Package Marking9.1 Preservation, Packaging, and PackingThe materialshall be prepared
33、for delivery in accordance with the produc-ers commercial practice or Practice D 3951 as specified insuch a manner as to ensure acceptance for safe delivery bycommon or other carriers to the point of delivery.9.2 MarkingIf specified in the purchase order, each indi-vidual item and test bar shall be
34、clearly identified with a lotserial number. Where parts are too small to be individuallyidentified, they may be grouped for this purpose.10. Keywords10.1 high-density metal; tungstenASTM International takes no position respecting the validity of any patent rights asserted in connection with any item
35、 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 technical commi
36、ttee 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 consideration at a me
37、eting 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 Harbor Drive,
38、 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).B777073
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