US PATENT SUBCLASS 75 / 228
.~ Consolidated metal powder compositions

Current as of: June, 1999
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75 /   HD   SPECIALIZED METALLURGICAL PROCESSES, COMPOSITIONS FOR USE THEREIN, CONSOLIDATED METAL POWDER COMPOSITIONS, AND LOOSE METAL PARTICULATE MIXTURES

300  DF  COMPOSITIONS {5}
228.~ Consolidated metal powder compositions {4}
229  DF  .~.~> Flake or fibrous constituent or fibrous grain structure
230  DF  .~.~> With nonmetal constituent - Silicon(Si) considered a metal (e.g., cermet, etc.) {5}
245  DF  .~.~> Base metal one or more Transition metal {2}
249  DF  .~.~> Base metal one or more of Beryllium(Be), Magnesium(Mg), or Aluminum(Al) {1}

DEFINITION

Classification: 75/228

Consolidated metal powder compositions:

(under subclass 300) Composition comprising free-metal containing powder or particles which have been united to form a self-sustaining mass.

(1) Note. "Powder" is defined as a mass of particles, that is, portions of matter so small that they are not ordinarily handled as individual units. According to Metals Handbook, 8th Edition, 1961, Volume 1, page 28, metallic powders then used in powder metallurgy had a particle size within the range of 0.1 to 1,000 microns in their largest dimension, as determined by screens or other suitable instruments. Powder particles generally are distinguished from filamentary particles in that their shape and length-to-diameter ratio are such that in the dry state the particles will not hold together as a coherent article without the application of pressure and or heat, that is, will not become entangled.

(2) Note. This and the indented subclasses include compositions made without any melting or fusion of the particles, as well as those made by sintering, that is, a

process in which a portion of metal particle is alloyed, bonded, brazed, coalesced, partly fused or welded to a portion of an adjacent metal particle due to the application of heat, or heat and pressure. Reference: Everhart, J. L., et al., "Mechanical Properties of Metals and Alloys", Circular of the National Bureau of Standards, C 447, 1943, page 16.

(3) Note. The composition may contain nonmetal material, but for classification in this subclass, the claimed product must have a metallic matrix, that is, must have a continuous metal phase in which the nonmetallic material is dispersed as a discontinuous phase. In the absence of a more explicit description, such a situation may be assumed when (a) the composition contains more than 40% metal; (b) the composition is prepared by a process which would inherently unite the metal particles without uniting the nonmetal component; or (c) the composition is described as nonmetal particles "cemented" with a metal.

(4) Note. Where a patent contains a claim to a consolidated metal powder composition and, in addition, one or more claims to (a) a process for making the composition and/or (b) an ingredient or unconsolidated mixture for use in the process, the patent is classified in this or the indented subclasses (228+) and cross-referenced to the other subclass, even though such other subclass may precede this in the schedule of this class (75).

(5) Note. Those patents are placed in this subclass (228) which claim all metal compositions wherein the base metal may be (a) either a transition or nontransition metal, or (b) a nontransition metal not provided for below, that is, the Alkali metals (i.e., Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Cesium (Cs), and Francium (Fr)); the Alkaline earth metals (i.e., Calcium (Ca), Strontium (Sr), Barium (Ba), and Radium (Rd)); Gallium (Ga), Indium (In); Thallium (Tl); Silicon (Si), which is considered a metal in this and its indented subclasses; Germanium (Ge); Tin (Sn); Lead (Pb); Arsenic (As); Antimony (Sb); and Bismuth(Bi).

(6) Note. In this and the indented subclasses a "metal silicide" is considered to be an intermetallic compound or alloy. (7) Note. The order of superiority among various alloy, metallic composition and metal stock areas and methods of manufacture involving them is given in the class definition under Lines With Other Classes and Within This Class.

SEE OR SEARCH THIS CLASS, SUBCLASS:

251, for unconsolidated mixtures of metal powder.

SEE OR SEARCH CLASS

102, Ammunition and Explosives,

283+, for a solid propellant form defined in such terms as "a generally perforated propellant mass," "a configured mass, i.e., sheet," with at least one dimension specified, or a porous mass in combination with an ancillary perforation extending therethrough.

106, Compositions: Coating or Plastic,

403+, for pigments, fillers, and aggregates containing metal powder.

148, Metal Treatment,

126.1, for processes involving heat treatment of metal powders, or nonconsolidated metal powder compositions.

149, Explosive and Thermic Compositions or Charges, especially 37+, for articulate metals in combination with an oxidant component.

174, Electricity: Conductors and Insulators,

118, for a device of that class insulated with powdered or granular compositions, and subclass 137 for insulator devices, per se.

228, Metal Fusion Bonding,

19, for an apparatus of that class with a means to compact applied flux.

252, Compositions,

62.51, for magnetic compositions having a nonmetal matrix; subclasses 181.1+ for "getter" compositions; and subclasses 500+ for electrically conductive compositions having a nonmetal matrix.

264, Plastic and Nonmetallic Article Shaping or Treating: Processes,

109+, particularly subclasses 111, for processes directed to forming of articles by uniting of discrete, bulk assembled particles. See the search notes to Class 264 in Class 29, subclass 602, and see the definitions in Class 264 and pertinent subclasses as cited herein for the line between these classes.

285, Pipe Joints or Couplings,

422, for such articles made of particular metal compositions.

338, Electrical Resistors,

223+, for a granular or powdered resistor element.

419, Powder Metallurgy Processes,

1+, for powder metallurgy processes which include use of heat.

420, Alloys or Metallic Compositions, appropriate subclasses for metallic compositions made by fusing (melting) the metals. A composition made by consolidating loose metal particles with heat and/or pressure is proper for

228, unless either (a) all the components are melted or dissolved, or (b) a part of the components are melted and the mass is treated as a fluent liquid, e.g., by stirring, pouring, etc. Cases of doubt will be resolved in favor of placement in subclass 228.

423, Chemistry of Inorganic Compounds,

1+, for processes of treating mixtures such as alloys to obtain a metal compound therefrom.

425, Plastic Article or Earthenware Shaping or Treating: Apparatus,

78, for apparatus for forming products by uniting associated particles of metallic elements, or alloys, or amalgams.

428, Stock Material or Miscellaneous Articles,

539.5, 545 and 546+ for material or articles of that class containing consolidated metal powder, subclass 570 for a composite metallic powder, and subclass 613 for porous, nonparticulate metallic stock material. 501, Compositions: Ceramic, appropriate subclasses for ceramic compositions having metal powder, but lacking a continuous metal matrix.

520, Synthetic Resins or Natural Rubbers, particularly Class 523,

1+, for a synthetic resin or natural rubber containing an ingredient which may be metallic.