TM_B_777_
_15
Designation:B77715Standard Specification forTungsten Base,High-Density Metal1This standard is issued under the fixed designation B777;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 parentheses indicates the year of last reapproval.Asuperscript epsilon()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 mixtures,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 This specification describes physical,mechanical,andmicrostructural testing of a material lot based on the use of testcoupons,not actual parts.Sintered properties typically varyboth with part size and sampling location within a given part.Results obtained from coupon testing may therefore differ fromthe properties of a specific location in a larger part.1.3 Intended UseParts made from this material are in-tended for uses such as weights or counter-balances in static ordynamic balancing,high-speed rotating inertia members,ra-diation shielding,hypervelocity impact,and vibration-dampingapplications.In selecting the appropriate alloy for a givenapplication,it is important to note that as the tungsten contentof the alloy is increased,stiffness,radiation attenuation,anddensity increase with an accompanying decrease in attainableductility.1.4 Special ApplicationsFor particular applications,prop-erties or requirements other than those specified in Sections 5,6,and 7 of this specification may be important.These alloysmay contain elements which make them weakly ferromagnetic.Where freedom from magnetic response is required,thisshould be specified in the purchase order.Class 4 is notavailable in a non-magnetic grade.For purposes of thisspecification,non-magnetic material is defined as materialhaving a maximum magnetic permeability of 1.05(see TestMethod A342).Also for special applications involving largesections,methods for determining internal quality,such asmechanical testing of specimens excised from these largersections or suitable nondestructive tests may be applied.If suchpart property data are required,an additional part-specific testprogram shall be specified in the purchase order.1.5 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.2.Referenced Documents2.1 ASTM Standards:2A342 Test Methods for Permeability of Weakly MagneticMaterialsB311 Test Method for Density of Powder Metallurgy(PM)Materials Containing Less Than Two Percent PorosityD3951 Practice for Commercial PackagingE3 Guide for Preparation of Metallographic SpecimensE8/E8M Test Methods for Tension Testing of Metallic Ma-terialsE18 Test Methods for Rockwell Hardness of Metallic Ma-terialsE407 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 specified(see 4.1).4.Ordering Information4.1 Orders for tungsten base,high-density metal shouldspecify the following:4.1.1 Title,designation,and year of issue of thisspecification,4.1.2 Class,(see 3.1),4.1.3 Quantity,4.1.4 Levels of preservation and packing(see 9.1),4.1.5 Special markings,if required(see 9.2),4.1.6 Method of hardness testing,if different from Rockwell“C”(see Table 1),1This specification is under the jurisdiction of ASTM Committee B10 onReactive and Refractory Metals and Alloys and is the direct responsibility ofSubcommittee B10.04 on Molybdenum and Tungsten.Current edition approved Dec.1,2015.Published December 2015.Originallyapproved in 1987.Last previous edition approved in 2013 as B777 07(2013).DOI:10.1520/B0777-15.2For 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 Document Summary page onthe ASTM website.3Available from DLA Document Services,Building 4/D,700 Robbins Ave.,Philadelphia,PA 19111-5094,http:/quicksearch.dla.mil.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.1.7 Freedom of parts from magnetic response,if required(see 1.4),and4.1.8 Dimensions and tolerances.5.Materials and Manufacture5.1 MaterialsThe raw materials shall be a mixture ofloose metal powders consisting mainly of tungsten with somecombination of binder elements such as copper,nickel,iron,orother which,by sintering,will produce sintered shapes meetingthe requirements of this specification.6.Chemical Composition6.1 The specified cla