1、Designation: B243 11B243 12Standard Terminology ofPowder Metallurgy1This standard is issued under the fixed designation B243; 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 indica
2、tes the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This terminology standard includes definitions that are helpful in the interpretation and application of powder metallurgyterms.2. Referenced Documents2.1 ASTM Sta
3、ndards:B331 Test Method for Compressibility of Metal Powders in Uniaxial Compaction3. Terminology3.1 PowderTerms associated with production, characterization, use, and testing of metal powders.3.1.1 Table of Contents1. Powders:1.0 General, 3.1.21.1 Processes to Produce Powder, 3.1.31.2 Types of Powd
4、er, 3.1.41.3 Shapes of Powder Particles, 3.1.51.4 Additives to Powder, 3.1.61.5 Treatment of Powder, 3.1.71.6 Properties of Powder, 3.1.81.7 Procedures to Evaluate Powder, 3.1.91.8 Equipment to Evaluate Powder, 3.1.102. Forming:2.0 General, 3.2.12.1 Processes for Compacting, 3.2.22.2 Conditions of C
5、ompacting,2.3 Tools Used for Compacting, 3.2.32.4 Phenomena Resulting from Compaction, 3.2.42.5 Properties of Compacts, 3.2.62.6 Forging, 3.2.72.7 Metal Injection Molding, 3.2.83. Sintering:3.1 Process for Sintering, 3.3.13.2 Conditions During Sintering, 3.3.23.3 Phenomena Resulting from Sintering,
6、3.3.33.4 Properties of Sintered Parts, 3.3.43.5 Procedure to Evaluate Sintered Parts, 3.3.53.6 Removal of Binders, 3.3.64. Postsinter Treatments:4.1 Processes, 3.4.11 This terminology is under the jurisdiction of ASTM Committee B09 on Metal Powders and Metal Powder Products and is the direct respons
7、ibility of SubcommitteeB09.01 on Nomenclature and Technical Data.Current edition approved Nov. 15, 2011July 15, 2012. Published December 2011October 2013. Originally approved in 1949. Last previous edition approved in 20102011as B243 10.B243 11. DOI: 10.1520/B0243-11.10.1520/B0243-12.This document i
8、s 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 accurately, ASTM recommends that users consult prior editions as approp
9、riate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15. Miscellaneous:5.1 Definitions, 3.5.15.2 Processes, 3.5.25.3
10、Materials, 3.5.33.1.2 General:agglomerate, nseveral particles adhering together.metal powder, nparticles of elemental metals or alloys, normally less than 1000 m (1 mm) in size.particulate matter, nsee powder.PM, nthe acronym for powder metallurgy.powder, nparticles that are usually less than 1000 m
11、 (1 mm) in size.powder metallurgy, nthe production and utilization of metal powders.3.1.3 Processes to Produce Powder:air classification, nthe separation of powder into particle size fractions by means of an air stream of controlled velocity.atomization, nthe dispersion of a molten metal into partic
12、les by a rapidly moving gas or liquid stream or by mechanical means.chemical deposition, nthe precipitation of one metal from a solution of its salts by the addition of another metal or reagentto the solution.chemically precipitated metal powder, npowder produced by the reduction of a metal from a s
13、olution of its salts either by theaddition of another metal higher in the electromotive series or by other reducing agent.classification, nseparation of a powder into fractions according to particle size.disintegration, nthe reduction of massive material to powder.gas classification, nthe separation
14、 of powder into particle size fractions by means of a gas stream of controlled velocity.granulation, nthe production of coarse metal particles by pouring the molten metal through a screen into water (shotting) orby violent agitation of the molten metal while solidifying.milling, nthe mechanical trea
15、tment of metal powder, or metal powder mixtures, as in a ball mill, to alter the size or shape ofthe individual particles or to coat one component of the mixture with another.pulverization, nthe reduction in particle size of metal powder by mechanical means, a specific type of disintegration.reduced
16、 metal powder, nmetal powder produced, without melting, by the chemical reduction of metal oxides or othercompounds.3.1.4 Types of Powder:atomized metal powder, nmetal powder produced by the dispersion of a molten metal by a rapidly moving gas, or liquidstream, or by mechanical dispersion.carbonyl p
17、owder, na metal powder prepared by the thermal decomposition of a metal minuted powder, na powder produced by mechanical attrition of solid metal or pletely alloyed powder, nsee pre-alloyed posite powder, na powder in which each particle consists of two or more distinct constituents.dendritic powder
18、, nparticles, usually of electrolytic origin, having the typical pine tree structure.diffusion-alloyed powder, na partially alloyed powder produced by means of a diffusion anneal.electrolytic powder, npowder produced by electrolytic deposition or by the pulverization of an electrodeposit.hybrid-allo
19、y powder, na pre-alloyed or diffusion-alloyed powder to which either elemental or master-alloy metal powders havebeen admixed.hydrogen-reduced powder, npowder produced by the reduction of a metal oxide in an atmosphere containing hydrogen.master-alloy powder, na powder with high alloy concentration,
20、 designed to be diluted when mixed with a base powder toproduce the desired composition.matrix metal, nthe continuous phase of a polyphase alloy or mechanical mixture; the physically continuous metallicconstituent in which separate particles of another constituent are embedded.mechanically alloyed p
21、owder, na composite powder produced by mechanically incorporating other constituents which aregenerally insoluble within the deformable particles of the matrix metal.mixed powder, nsee powder mixture.nanopowder, na powder consisting of particles typically less than 100 nm in size.partially alloyed p
22、owder, na powder in which the alloy addition or additions are metallurgically bonded to an elemental orpre-alloyed powder.powder mixture, na powder made by mixing two or more powders of differing chemical composition, particle size distribution,particle shape, or a combination of these characteristi
23、cs.pre-alloyed powder, npowder composed of two or more elements that are alloyed in the powder manufacturing process inwhich the particles are of the same nominal composition throughout. Synonymous with completely alloyed powder.premix, na uniform mixture of ingredients to a prescribed analysis, pre
24、pared by the powder producer, for direct use incompacting powder metallurgy products.B243 122sponge iron, na coherent, porous mass of substantially pure iron produced by solid-state reduction of iron oxide (for example,iron ore or mill scale).sponge iron powder, nground and sized sponge iron, which
25、may have been purified or annealed or both.sponge metal, nany porous metal produced by the reduction or decomposition of a compound at temperature below the meltingpoint of the metalsponge metal powder, na powder produced from a sponge metal by mechanical methods of size reduction.3.1.5 Shapes of Po
26、wder Particles:acicular powder, nneedle-shaped particles.flake powder, nflat or scale-like particles whose thickness is small compared with the other dimensions.granular powder, nparticles having approximately equidimensional nonspherical shapes.irregular powder, nparticles lacking symmetry.needles,
27、 nelongated rod-like particles.nodular powder, nirregular particles having knotted, rounded, or similar shapes.platelet powder, na powder composed of flat particles having considerable thickness (as compared with flake powder).spherical powder, nglobular-shaped particles.3.1.6 Additives to Powder:bi
28、nder, na cementing medium; either a material added to the powder to increase the green strength of the compact, and whichis expelled during sintering; or a material (usually of relatively lower melting point) added to a powder mixture for the specificpurpose of cementing together powder particles wh
29、ich alone would not sinter into a strong body.dispersion-strengthened material, na material consisting of a metal and finely dispersed, substantially insoluble, metallic ornonmetallic phase.feedstock, nin metal injection molding (MIM), a moldable mixture of metal powder and binder.lubricantmaterial
30、used to reduce inter-particle friction and the friction between the powder mass and the tooling.lubricant (admixed), na lubricant incorporated into a powder mixture.lubricant (die-wall), na lubricant applied to the tooling surfaces to facilitate ease of movement of the tooling and the removalof the
31、compact or part from the tooling.pore-forming material, na substance included in a powder mixture that volatilizes during sintering and thereby produces adesired kind and degree of porosity in the finished compact.3.1.7 Treatment of Powder:blending, nthe thorough intermingling of powders of the same
32、 nominal composition (not to be confused with mixing).cross-product contamination, nthe unintentional mixing of powders with distinct differences in either physical characteristicsor chemical composition or both.equalizing, nsee blending.mixing, nthe thorough intermingling of powders of two or more
33、materials.3.1.8 Properties of Powder:angle of repose, nthe basal angle of a pile formed by powder when freely poured under specified conditions onto a horizontalsurface.apparent density, nthe mass of a unit volume of powder, usually expressed as grams per cubic centimetre, determined by aspecified m
34、ethod.bulk density, nthe mass per unit volume of a powder under nonstandard conditions, for example, in a shipping container (notto be confused with apparent density).compactibility, na conceptual term, encompassing the powder characteristics of compressibility, green strength, edge retention,and la
35、mination tendency, that relates to the ability of a powder to be consolidated into a usable green pressibility, nthe capacity of a metal powder to be densified under a uniaxially applied pressure in a closed die.DISCUSSIONCompressibility is measured in accordance with Test Method B331 and may be exp
36、ressed numerically as the pressure to reach a specified density, oralternatively the density at a given pressure.2compression ratio, nthe ratio of the volume of the loose powder to the volume of the compact made from it. Synonymous withfill ratio.cut, nsee fraction.fill ratio, nsee compression ratio
37、.fines, nthe portion of a powder composed of particles which are smaller than a specified size, currently less than 44 m. Seealso superfines.2 See Test Method B331.B243 123flow rate, nthe time required for a powder sample of standard weight to flow through an orifice in a standard instrumentaccordin
38、g to a specified procedure.fraction, nthe portion of a powder sample that lies between two stated particle sizes. Synonymous with cut.green density, nthe mass per unit volume of an unsintered PM part or test specimen.hydrogen loss, nthe loss in weight of metal powder or of a compact caused by heatin
39、g a representative sample for a specifiedtime and temperature in a purified hydrogen atmospherebroadly, a measure of the oxygen content of the sample when appliedto materials containing only such oxides as are reducible with hydrogen and no hydride-forming element.impregnated density, nthe mass per
40、unit volume of a sintered PM part or test specimen, impregnated with oil or otherlubricants. Synonymous with density (wet).minus sieve, nthe portion of a powder sample which passes through a standard sieve of specified number. (See plus sieve.)oversize powder, nparticles coarser than the maximum per
41、mitted by a given particle size specification.particle size, nthe controlling lineal dimension of an individual particle as determined by analysis with sieves or other suitablemeans.particle size distribution, nthe percentage by weight, or by number, of each fraction into which a powder sample has b
42、eenclassified with respect to sieve number or microns. (Preferred usage: “particle size distribution by frequency.”)plus sieve, nthe portion of a powder sample retained on a standard sieve of specified number. (See minus sieve.)segregation, nthe separation of one or more constituents of a powder, fo
43、r example, by particle size or chemical composition.sieve fraction, nthat portion of a powder sample that passes through a standard sieve of specified number and is retained bysome finer sieve of specified number.sintered density, nthe mass per unit volume of a sintered PM part or test specimen not
44、impregnated with oil or other lubricant.Synonymous with density (dry).specific surface, nthe surface area of one gram of powder, usually expressed in square centimetres.subsieve fraction, nthe portion of powder passing through a 45-m (no. 325) sieve.superfines, nthe portion of a powder composed of p
45、articles that are smaller than a specified size, currently less than 10 m.tap density, nthe apparent density of the powder in a container that has been tapped under specified conditions.3.1.9 Procedures to Evaluate Powder:screen analysis, nsee sieve analysis.sieve analysis, nparticle size distributi
46、on; usually expressed as the weight percentage retained upon each of a series of standardsieves of decreasing size and the percentage passed by the sieve of finest size. Synonymous with screen analysis.sieve classification, nthe separation of powder into particle size ranges by the use of a series o
47、f graded sieves.3.1.10 Equipment to Evaluate Powder:powder flow meter, nan instrument for measuring the rate of flow of a powder according to a specified procedure.3.2 FormingTerms associated with consolidation of metal powders and mixes, including tooling, equipment, and character-ization of sinter
48、ed compacts.3.2.1 General:blank, na pressed, presintered, or fully sintered compact, usually in the unfinished condition, requiring cutting, machining, orsome other operation to give it its final shape.briquet, nsee pact, nan object produced by the compression of metal powder, generally while confin
49、ed in a die, with or without theinclusion of nonmetallic constituents. Synonymous with posite compact, na metal powder compact consisting of two or more adhering layers, rings, or other shapes of differentmetals or alloys with each material retaining its original pound compact, na metal powder compact consisting of mixed metals, the particles of which are joined by pressing orsintering or both, with ea
