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WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER (processes or devices for granulating materials in general B01J 2/00; making ceramics by compacting or sintering C04B, e.g. C04B 35/64; for the production of metals as such, see class C22; reduction or decomposition of metal compounds in general C22B; making alloys by powder metallurgy C22C; electrolytic production of metal powder C25C 5/00)
Definition statement
This subclass/group covers:

Special treatment of metallic powder, e.g. thermal, thermo-mechanical or chemical treatments, making agglomerates, mixing with lubricants or binders;

Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering or by the special shape of the product;

Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting;

Manufacture of articles from scrap or waste metal particles;

Making metallic powder or suspensions thereof using physical or chemical processes;

Powder metallurgical apparatus or equipment specifically adapted therefor, e.g. furnaces, retorts, sintering apparatus;

Metallic powders, per se, e.g. powder, mixture of powders or a mixture of a powder with a lubricating or binding agent

Relationship between large subject matter areas

B22F covers the making of metallic powder including a metal powder with specific physical characteristics. When the metal is present only as impurity, or when the subject matter does not refer to the manufacturing process itself but only refers to the use of it (e.g. dental implants using metal powder are classified in A61C 8/00), it is classified in the other places of IPC.

C22B 1/14 covers preliminary treatment of ores or scrap with organic or inorganic binders, e.g., agglomerating; briquetting, granulating; sintering.

C22C 1/05; C22C 1/10; C22C 33/02; C22C 47/14 cover the making of alloys by powder metallurgy using mixtures of metal powder with non-metallic powder, fibres or filaments.

C22F covers changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working, including special physical methods, e.g. treatment with neutrons.

C04B covers preparing or treating powders of inorganic compounds in preparation to the manufacturing of ceramic products, e.g., C04B 35/622. When the proportion of metal powder is present not like as impurity in the compounds, it is classified at B22F.

C08K covers use of inorganic or non-macromolecular organic substances as compounding ingredients, including metals as inorganic ingredient, e.g., C08K 5/56 organic compounds containing a metal-to-carbon bond. These compounds are not considered metal per se.

B01J 2/00 covers chemical or physical processes or devices for granulating materials in general.

B02C covers crushing, grinding or milling in general

References relevant to classification in this subclass
This subclass/group does not cover:
Non-ferrous alloys compositions made by powder metallurgy
Making alloys from mixtures of metal powder with non-metallic powder
Alloys based on metal compounds
Non-ferrous alloys containing other metal compounds
Making ferrous alloys by powder metallurgy
Making alloys containing metallic or non-metallic fibres or filaments by powder metallurgy

Examples of places where the subject matter of this subclass is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Making ceramics by compacting or sintering
Shaped ceramic products characterised by their composition
Burning or sintering process for ceramic compositions
Production or refining of metals; Pretreatment of raw materials
Sintering; Agglomerating for ores or scrap
Electrolytic production, recovery of refining of metal powder or metal masses
Informative references
Attention is drawn to the following places, which may be of interest for search:
Dental implants
Prostheses implantable into the body
Use of preparations for artificial teeth, for filling or for capping teeth
Materials for prostheses or for coating prostheses
Chemical or physical processes or devices for granulating materials in general
Catalysts comprising metals
Methods for preparing or activation of catalysts
Crushing, grinding or milling in general
Disposal of solid waste
Mechanical metal-working
Metal parts in the mould of a casting process
Soldering or unsoldering; Welding; Cladding or plating by soldering or welding
Abrasive tools
Cutting tools
Presses specially adapted for forming articles from material in particulate or plastic state
Layered products characterised by features of a layer formed of particles, e.g. chips, chopped fibres, powder
Printing
Chemical aspects of powdering or granulating of macromolecular substances
Metallic pigments or fillers
Compressing powdered coating material, e.g. by milling
Drilling tools
Parts of bearings; Use of special materials or surface treatments, e.g. for rust-proofing
Conductive material dispersed in non-conductive organic material
Magnets or magnetic bodies characterised by the magnetic materials therefore; Selection of materials for their magnetic properties in the form of particles, e.g. powder
Selection of the material for the legs of the junction comprising metals only
Elements or alloys used in electrodes
Printed circuits
Special rules of classification within this subclass

in B22F EC codes are also used for deep-indexing in combination with Indexing Code. Combination of codes are made to address supplementary information concerning processes or compositions, process sequences or information linked to processes or compositions. Each of these combinations start with a specific Indexing Code:

B22F 2998/00: supplementary information concerning processes or compositions relating to powder metallugy

B22F 2998/10: processes characterised by the sequence of their steps

B22F 2999/00: aspects linked to processes or compositions used in powder metallurgy

Examples (see e.g. US2005281701):

B22F 2998/00,B22F 1/0014: in §36-39 additional information is given on an embodiment having a bimodal size distribution;

B22F 2998/10,B22F 1/0059,B22F 3/004,B22F 3/093,B22F 3/02: from figure 4 it can be learned that a mould is filled with a mixture of metal powder and resin, vibration compacted and pressed

B22F 2999/00,B22F 3/004,B22F 3/093,B22F 2201/20: during the moulding and vibration compaction a vacuum is applied

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Compacting
join or press firmly together.
Metallic powder
covers powders which in addition to metals may contain a substantial proportion of non-metallic material.
Powder
includes particulate material of any geometrical shape, e.g. fibres, spheres, cubes, which are worked, obtained or behave in a manner similar to powder
Sintering
coalesce or cause to coalesce from powder into solid by heating.
Alloy
a composition of plural elements at least one of which is a free metal. Also includes material containing any combination of fibres, filaments, whiskers and particles, e.g. carbides, diamond, oxides, borides, nitrides or sulfides, embedded in a metallic matrix.
Furnace
covers kilns, ovens or retorts
Synonyms and Keywords

In patent documents the following words “apparatus”, “equipment” and “device” are often used as synonyms.

In patent documents the following keywords “residue”, “waste”, “remains”, “scrap”, “rejects” and “shred” are often used.

In patent documents the following keywords “compacting” and “compressing” are often used.

Special treatment of metallic powder, e.g. to facilitate working, to improve properties { (treatment of powder by mechanical means, e.g. by grinding, milling, rolling B22F 9/04) } ; Metallic powders per se, e.g. mixtures of particles of different composition (C04, C08 take precedence; { amorphous powder B22F 9/002} )
Definition statement
This subclass/group covers:

Metal particles per se as well as mixtures of metal particles with a lubricant, binding agent or organic material. Particles per se can have a specific size, size distribution, shape or structure. Treatment of metallic powder and coating thereof is also covered.

A special case, which is also covered by this subclass, concerns non-metallic or inorganic particles which have a metallic coating. Equally metal particles coated with non-metals or inorganic compounds are classified in subclass B22F 1/00. B22F 1/00 also covers powders containing a substantial proportion of non-metallic material. When the metal is present in a proportion significantly relevant so that it could not be seen as an impurity in the metallurgic process it must be classified in B22F 1/00.

Relationship between large subject matter areas

Compositions of metal and ceramic powder, e.g. cermets, are classified in C22C.

References relevant to classification in this group
This subclass/group does not cover:
Treatment of powder by mechanical means
Informative references
Attention is drawn to the following places, which may be of interest for search:
Ammunition shot
Shot peening
Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor; {Presses and furnaces}
Definition statement
This subclass/group covers:

Apart from the manufacturing of workpieces or articles from metallic powder, also the manufacturing of parts which are based on metallic fibres only (no matrix material) as well as processes starting from decomposable or reducible metal compounds.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Mechanical metal-working without essentially removing material; Punching metal
Forging; Hammering; Pressing; Forge Furnaces
Making forged or pressed products
Presses in general
Furnaces, Kilns, Ovens, or retorts in general; Open sintering or like apparatus
Special rules of classification within this group

Although B22F 3/12 specifies processes including both compacting and sintering, this group is mainly used for information concerning the container or model used during the compacting and sintering. For the compacting and sintering step, the more detailed subgroups under B22F 3/02 (compacting) and/or B22F 3/10 (sintering) are applied.

Press-moulding apparatus therefor
Definition statement
This subclass/group covers:

Press apparatuses specially adapted for metal powder pressing.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Presses in general
Special rules of classification within this group

Methods or special apparatuses for the filling of the moulds with powder are classified in B22F 3/003.

by explosive forces { (generating shock waves in general G10K 15/043) }
Definition statement
This subclass/group covers:

Processes in which compacting is accomplished through the use of shock waves or explosive forces, including processes that utilize a time-related detonating effect

Informative references
Attention is drawn to the following places, which may be of interest for search:
Application of shock-waves for chemical reactions or for modifying structures in general
Generating shock-waves in general
Special rules of classification within this group
using vibrations {or friction}
Definition statement
This subclass/group covers:

Compaction aided by vibrations or friction.

by using electric current {other than for infra-red radiant energy} , laser radiation or plasma (B22F 3/11 takes precedence) ; {by ultrasonic bonding (B22F 3/115 takes precedence) }
Definition statement
This subclass/group covers:

All sintering processes involving EM-wave energy: electric current, plasma, laser, microwave, etc and ultra-sonic bonding.

References relevant to classification in this group
This subclass/group does not cover:
Selective sintering processes, e.g. stereolithography
Rapid manufacturing and prototyping of 3D objects by additive depositing, agglomerating or laminating of plastics material
Stereolithographic techniques for making dental prostheses
Selective sintering of ceramic or cementitious material
Informative references
Attention is drawn to the following places, which may be of interest for search:
Laser welding and relative movement between laser beam and workpiece
Selective printing
by spraying molten metal, i.e. spray sintering, spray casting { (also classified in C23C 4/121, C23C 4/185) }
Definition statement
This subclass/group covers:

(hot) spraying of molten metal wherein the sprayed material forms the product (i.e. not as a coating process).

References relevant to classification in this group
This subclass/group does not cover:
Cold spraying of metal
Informative references
Attention is drawn to the following places, which may be of interest for search:
Thermal spraying fibre reinforced material
Adding compound dispersions to the spray
Special rules of classification within this group

These documents are also classified in C23C 4/121 (spraying molten metal) and C23C 4/185 (separation of coating from substrate) as well as B22D 23/003 (moulding by spraying metal on a surface).

After-treatment of workpieces or articles { (B22F 3/1146 takes precedence) }
Definition statement
This subclass/group covers:

Chemical or thermal after-treatments and mechanical treatments only in as far as material is removed from the surface, such as making recesses or grooves, honing, polishing, milling, grinding, carving etc.

Special rules of classification within this group

The after-treatment is further specified by means of an Indexing Code.

Impregnating { (making ferrous alloys by impregnation C22C 33/0242) }
References relevant to classification in this group
This subclass/group does not cover:
Porous articles or workpieces formed by impregnation remaining porous
Informative references
Attention is drawn to the following places, which may be of interest for search:
Non-ferrous alloys obtained by impregnation of a powder metallurgy product
Making ferrous alloys by impregnation
Impregnating a ceramic preform with molten metal
Apparatus for impregnation
Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
Definition statement
This subclass/group covers:

Processes in which a defined geometrical configuration of a final product is specified, and also moulds, turbine components other than blades, engine parts different from piston rings, flat products and articles to be fractured or separated into parts.

of turbine blades
Informative references
Attention is drawn to the following places, which may be of interest for search:
Turbine blades
Making turbine blades (by machining)from one piece from several pieces
of threaded articles, e.g. nuts
Informative references
Attention is drawn to the following places, which may be of interest for search:
Screw bolts
Making screw-threaded elements (e.g. nuts, bolts)
of toothed articles, e.g. gear wheels; of cam discs
Informative references
Attention is drawn to the following places, which may be of interest for search:
Making gears or toothed racks
Gear wheels by stamping
Gear wheels by rolling
Gear wheels forged or pressed
Coupling members, e.g. clutch systems
Making gear wheels by "other" processes
Toothed gearings
Mechanically actuated clutches
Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting { wherein at least one part is obtained by sintering or compression (application of coating layers by use of metal powders, see C23C) }
Definition statement
This subclass/group covers:

Manufacture of composite parts (limited geometry) and layers ("infinite"), including porous layers or parts, comprising metallic powder, by sintering the powder, with or without compacting

References relevant to classification in this group
This subclass/group does not cover:
Coatings applied by use of metal powder (not involving compression and/or sintering)
Informative references
Attention is drawn to the following places, which may be of interest for search:
Layered products, essential comprising metal
Layered products characterised by the non-homogeneity or physical structure of a layer, comprising fibres or filaments formed of particles foamed or porous material combinations thereof in at least 2 layers
Methods or apparatus for laminating
Layered products characterised by the relation between layers
of composite workpieces or articles from parts, e.g. to form tipped tools { (B22F 7/002 takes precedence) }
Informative references
Attention is drawn to the following places, which may be of interest for search:
Connecting cutting edges by brazing
Making cutting tools
Tools for cutting or boring with bits of special material or diamond bits
Hand cutting tools
Tools for grinding, with metallic binder
Earth or rock drilling bits, with diamond insertswith button type inserts
{involving the connection or repairing of preformed parts}
Definition statement
This subclass/group covers:

Only connecting (i.e not co-forming or in-situ forming) or repairing.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Repairing methods or devices for turbine blades
Manufacture of articles from scrap or waste metal particles
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Scrap, waste
swarf, residue, remains, rejects, shred
Making metallic powder or suspensions thereof
Informative references
Attention is drawn to the following places, which may be of interest for search:
Granulation of slag
Granulation of ores or scrap
{Rapid solidification processing}
Definition statement
This subclass/group covers:

Solidification by means of quenching rates above 104 C/s.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Processes or devices for granulating materials, in general
Metallic powder obtained by crushing, pulverising, disintegrating in general; milling grain
starting from liquid material
Definition statement
This subclass/group covers:

Only starting from melts.

starting from gaseous material
Definition statement
This subclass/group covers:

Processes employing a gaseous precursor of the powder, plasma, or the evaporation of metal.

using chemical processes
Definition statement
This subclass/group covers:

Including the recovery of one metal from a mixture/solution containing multiple metals.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Electrolytic production, recovery or refining of metal powders
By hydrogen absorption / desorption
starting from solid metal compounds
Relationship between large subject matter areas

Direct reduction of iron ores: C21B 13/00

General processes of reducing to metals: C22B 5/00

Dry reduction processes for obtaining specific non-ferrous metals: C22B

Informative references
Attention is drawn to the following places, which may be of interest for search:
Controlled atmosphere, or pulverulent material; Adjusting the composition of the atmosphere
{of metal carbonyls}
References relevant to classification in this group
This subclass/group does not cover:
General method of reducing metals from metal carbonyls
Manufacturing of iron from iron carbonyl
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Last Modified: 10/11/2013