US PATENT CLASS 148
Class Notes


Current as of: June, 1999
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148 /   HD   METAL TREATMENT



DEFINITION

Classification: 148/

A. This is the generic class in the art of treating metal to modify or maintain the internal physical structure (i.e., microstructure) or chemical properties of metal. Most process subject matter under this class relates to treating solid or semisolid metal with heat, without melting a substantial portion thereof, and also includes the

combination of significant heating and working not provided for in other metal working classes. However, casting or casting and working of molten metal, if combined with significant heat treatment to change the microstructure of the solid metal resulting therefrom is acceptable in this class. Cooling of metal to produce microstructure change is proper for this class.

B. This class includes processes of treating metal to intentionally develop, improve, modify, or preserve the magnetic properties of a free metal or alloy, occurring alone or mixed with one or more components.

C. This class includes processes of reactive coating of metal wherein an externally supplied carburizing or nitriding agent is combined with the metal substrate to produce a carburized or nitridized or carbonitrided coating thereon or a uniformly carburized, nitrided, or carbonitrided metal alloy containing a metal element from said substrate.

D. This class includes processes of reactive coating of metal wherein an externally supplied agent combines with the metal substrate to produce a coating thereon which contains at least one element from said metal substrate (e.g., oxidizing, boronizing, etc.).

E. This class includes processes of chemical-heat removing (e.g., flame cutting, etc.) or burning (i.e., oxidizing) to remove a portion of a metal workpiece.

F. This class includes: (1) elemental metal, alloy or metallic composition which is a product of a process under section A, above; (2) elemental metal, alloy, or metallic composition or multi-layered products under section B or C above; (3) elemental metal, alloy, or metallic composition which is the product of a significant Class 164 metal founding step; (4) elemental metal, alloy, or metallic composition which is the product of the dispersion of particulate matter in molten metal which particulate matter retains its identification in the final state; and (5) elemental metal, alloy, or metallic composition which contains an amorphous or shape memory property.

G. This class includes compositions employed in the treatment of solid metal and processes for preparing the same when not otherwise classifiable.

H. This class includes electrically conductive semiconductor stock which is essentially homogeneous and has at least two contiguous layers differing in the number of unbound electrons and/or differing in energy gap levels which exhibit a junction between layers (e.g., P-N type, etc.). For amplification of A-H, see Subclass References to the Current Class, below.

RULES OF PATENT PLACEMENT

Patents have been placed in this class employing the so-called "genus-species" rule. Following this rule as between a generic subclass and its indents, a species unprovided in any indented subclass is specifically classified in the generic subclass. Thus, a patent containing claims to both a provided species and an unprovided species is placed as original in the generic subclass as the first (i.e., highest) appearing subclass and cross-referenced to the indented subclass having the provided species. A patent containing claims only for species having provided subclasses is placed as original in the first (i.e., highest) appearing provided subclass and cross-referenced to the other (i.e., lower) appearing subclasses.

Following the "genus-species" rule, all mandatory original and cross-references only appear in the highest subclasses providing therefor. The claims identify the mandatory original and cross-references. However, if the claims are all generic, the specification is used to determine mandatory placement of the disclosed species, only if related to features in the claim language.

LINES WITH OTHER CLASSES

A. METAL CASTING, METAL FUSION BONDING, MACHINING, OR WORKING CLASSES

For purposes of distinguishing over the metal casting, metal fusion bonding, machining, or working classes, significant heat treatment must be present to be proper for Class 148. Significant heat treatment occurs when temperature or heating or cooling rate is provided in a nonworking, noncasting, nonfusion-bonding, or nonmachining related step or when microstructure description is utilized in the claim to describe the result of the heating or cooling treatment of solid or semisolid metal. Working at a specified temperature without mention of microstructure is not significant heat treatment for Class 148. The mere use of the term "ageing" or "tempering" will be considered significant heat treatment. Except for "workhardening", the use of the term "hardening" will be considered significant heat treatment. "Quenching" will be considered significant heat treatment lacking an indication that it means simply returning to a convenient working temperature. "Stress-relief-annealing" will remain in the metal working classes. Working metal in the "superplastic" state or during "dynamic-recrystallization" remains in the working classes unless a temperature is provided. "Ion implantation" of a metal substrate will be a sufficient indication of microstructural change to place classification in Class 148. High frequency vibration of solid metal for purposes of changing the microstructure thereof is sufficient to take a combination thereof with the above operations to Class 148 as an original. When combined with working, "annealing", per se, will remain in the metal working classes. However, annealing at a specified temperature goes in Class 148. Merely, heating or cooling a

metal to a working temperature is not significant heat treatment. In summary, the presence in any step of a significant heat treatment as hereinabove described is sufficient to place the classification in Class 148.

B. CHEMICAL PROCESSES OF MANUFACTURING METALS OR ALLOYS, METALLIC COMPOSITIONS AND METALLIC STOCK CLASSES IN ORDER OF SUPERIORITY.

Historically, placement of originals among the classes for chemical processes of manufacturing metals or alloys, metallic compositions classes and metallic stock classes did not depend upon the most comprehensive claims and did not follow superiority of statutory categories of invention (i.e., process of using, product or manufacture, process of making, apparatus for performing a process and material). Within these metallurgical processes, metallic composition and metallic stock classes, placement depends upon complex lines established through experience. To simplify placement, the following hierarchy containing the essence of historical placement for these classes was previously established to settle conflicts between the classes listed thereunder with the first listed or higher class controlling placement, if claims are present therefor and regardless of statutory category. If a class other than those listed hereinunder is involved, consideration of the other class is based upon relevant lines, comprehensiveness, and superiority of statutory categories of invention only with respect to the other class. Having determined the controlling class, placement of the original goes by the hierarchy within the class and not according to the following list.

The superiority among the various metal, alloy, and metal stock areas, and chemical methods of manufacturing them, is provided in order under the search class notes as follows: Class 419, Powder Metallurgy, appropriate subclasses for processes of treating metal powder utilizing a sintering or compacting operation and including post-treatment operations if combined with the sintering or compacting operation. If the starting material is preconsolidated, and there is no actual sintering or consolidating step present, placement goes as original to Class 148, subclass 514 provided hierarchically hereinbelow.

Class 148, Metal Treatment, subclasses 22-30 for compositions for treatment of solid metal.

Class 75, Specialized Metallurgical Processes, Compositions for Use Therein, Consolidated Metal Powder Compositions, and Loose Metal Particulate Mixtures, subclasses 300, 301, and 303+ for gaseous, liquid, or solid treating compositions for liquid metal or charges, and subclass 302 welding rod defined by composition.

Class 75, Specialized Metallurgical Processes, Compositions for Use Therein, Consolidated Metal Powder Compositions and

Loose Metal Particulate Mixtures, subclasses 228-250, consolidated metal powder compositions and subclasses 252-255, loose metal particulate mixtures.

Class 420, Alloys or Metallic Compositions, claimed as products.

Class 148, Metal Treatment, subclasses 95-122, 194-287, and 500-714 providing for processes of modifying or maintaining the internal physical structure (i.e., microstructure) or chemical properties of metal, processes of reactive coating of metal and processes of chemical-heat removing (e.g., flame-cutting) or burning of metal. However, if metal casting, fusion bonding, machining or working is involved, there is a requirement of significant heat treatment as described in "A. Metal Casting, Metal Fusion Bonding, etc." above.

Class 148, Metal Treatment, subclasses 33-33.6, barrier layer stock material and subclasses 300-337 and 400-442, stock.

Class 75, Specialized Metallurgical Processes, Compositions for Use Therein, Consolidated Metal Powder Compositions and Loose Metal Particulate Mixtures, subclasses 331+, processes of making solid particulate alloys directly from liquid metal, and subclasses 343+, processes of producing or purifying alloys in powder form.

Class 75, Specialized Metallurgical Processes, Compositions for Use Therein, Consolidated Metal Powder Compositions and Loose Metal Particulate Mixtures, subclasses 10.1+ and 10.67+, processes of making alloys by electrothermic, electromagnetic, or electrostatic processes.

Class 420, Alloys or Metallic Compositions, for processes of manufacture.

Class 75, Specialized Metallurgical Processes, Compositions for Use Therein, Consolidated Metal Powder Compositions and Loose Metal Particulate Mixtures, subclasses 330+, processes of making metal and processes of treating liquid metals and liquid alloys and consolidating metalliferous material. 205, Electrolysis: Processes, Compositions Used Therein, and Methods of Preparing the Compositions, particularly for processes of electrocoating of metal. At this time, Class 205 is a subdivision of Class 204 and therefore all notes concerning Class 204 should be consulted when determining the relationship to Class 148.

204, Chemistry: Electrical and Wave Energy, processes. Combinations of reactive coating of metal and electrocoating of metal go to Class 204 as original. See C, Chemical Coating, Cleaning, Etching And Manufacturing Classes, below for the line between Class 148 and Class 204. If metal casting, fusion bonding, machining, or working is included see "A. Metal Casting, Metal Fusion Bonding, etc." above to

determine if this is proper for Class 148.

164, Metal Founding, subclasses 1+, processes. See the line between Class 164 and Class 148 under A, Metal Casting, Metal Fusion Bonding, Machining, Or Working Classes, above.

266, Metallurgical Apparatus, subclasses 44+, processes of operating metallurgical apparatus.

C. CHEMICAL COATING, CLEANING, ETCHING AND MANUFACTURING CLASSES.

If there is a combination of chemical coating, cleaning, etching or chemical treating of metal and metal casting, fusion bonding, machining, or working with significant heat treatment in any step of metal to modify or maintain the internal physical structure (i.e., microstructure) or chemical property of metal, the combination goes in Class 148 as an original. To determine what constitutes significant heat treatment refer to "A. Metal Casting, Metal Fusion Bonding, etc." above. In the absence of casting, welding, machining, or working, the combination of treating metal with chemicals or chemical compositions and a separate step heat treatment to modify or maintain the internal physical structure or chemical property of metal, placement as an original goes to Class 148 except as indicated in the following lines. It is noted that heat treatment includes a cooling of metal for Class 148 purposes. If chemical heat-cutting (e.g., flame cutting) or burning (i.e., oxidizing), ion implantation, high frequency vibration to change microstructure, carburizing, nitriding, or reactive coating of metal is claimed, combinations with other classes involving treating metal with chemicals or chemical compositions will go to Class 148, subject to the following exceptions.

Also see References to Other Classes, below, that reference this section.

D. SEMICONDUCTOR DEVICE MAKING AND SEMICONDUCTOR STOCK

Class 438 is the residual class for (a) multiple operations (steps) for producing a semiconductor having a junction or semiconductor device having a junction, usually between P-type and N-type material or (b) an unit operation involving semiconductor material, not elsewhere provided. Class 438, subclasses 795+, provides for processes of heat treatment of semiconductor material to change some characteristic thereof. Since in certain instances semiconductor material could include metallic compositions containing metal, placement goes to Class 438 as original over Class 148 if during the heat treatment there is either a change in the internal physical structure (i.e., microstructure) or chemical properties since that is in essence a change in the property of the semiconductor materials overall properties whether those properties are expressed in terms of a change in conductance or not. However, it is required that the metal

composition undergoing the heat treatment must be identified or perceived as semiconductor material. If perceived, a mandatory cross is made in Class 148.

Semiconductor stock in Class 148, subclasses 33-33.6, must be essentially homogeneous and have at least two contiguous layers differing in the number of unbound electrons and/or differing in energy gap levels, which exhibit a junction between the layers. Class 252, subclass 62.3, is the location of compositions specialized and designed for use as one layer which when combined with another such layer would provide an interface exhibiting barrier layer properties (e.g., as could exist in Class 148, subclasses 33-33.6, stock, if the junction thereof were between P-type and N-type semiconducting materials, etc.). LINE WITH CLASS 29 AND CLASS 164

Combinations of casting and working are located in Class 29. However, combinations of casting and heat treatment for purposes of modifying or maintaining the internal physical structure (i.e., microstructure) or chemical properties of metal go as original to Class 148. Combinations of casting and metal fusion bonding, machining, or working go to Class 148, if there is significant heat treatment as defined hereinabove. In continuous casting operations, wherein the contiguous product is still connected to the casting surface, a step involving significant heat treatment of the solid or semi-solid metal which occurs outside or away from the molding surface goes to Class 148. However, chemical heat removing (e.g., flame-cutting, etc.) or burning (i.e., oxidation) of a continuously cast metal goes to Class 164, if some of the continuously cast and contiguous product is connected to the shaping surface. Cutting operations in the mold go to Class 164. Combinations of reactive coating, ion implantation or high frequency vibration to change microstructure and casting go to Class 148 if they occur outside the mold.

LINE WITH CLASS 204 AND CLASS 427

While the combination of etching and electrocoating or sputter-coating or the combination of electrocoating or sputter-coating and a Class 427 coating operation is proper for Class 204, the inclusion of a post-treatment involving a separate Class 148 operation to modify or maintain the internal physical structure or chemical properties of metal deposited by the Class 427 operation takes the overall combination to Class 148 as original.

It is further noted that the other areas of Class 204, follow a different line than the electrocoating or sputter-coating with respect to Class 148. The presence in any step of an operation proper for Class 148, if claimed independently, is sufficient to take the noncoating Class 204 operation to Class 148 as original. In the context of Class 204, electrorefining to recover metal from solution is not

considered electrocoating even though an electrode is plated.

LINE WITH CLASS 205 AND CLASS 204

See Class 205, Electrolysis: Processes, Compositions Used Therein, and Methods of Preparing the Compositions, particularly subclasses for processes of electrocoating of metal. At this time, Class 205 is a subdivision of Class 204 and therefore all notes concerning Class 204 should be consulted when determining the relationship to Class 148.

LINE WITH CLASS 427 AND CLASS 204

Class 148 provides for certain coating processes, per se, if the substrate is metal. The species of coating, per se, proper for Class 148 include carburizing, nitriding, carbonitriding, or reactive coating of a metal substrate. If there is a combination coating operation for Class 427 and a Class 148 treatment of solid or semi-solid metal in a step separate from the coating step to modify or maintain the internal physical structure (i.e., microstructure) or chemical properties of metal, the combination goes as original to Class 148 whether or not the treatment is preparatory to the Class 427 coating operation or is a post-treatment of the coating or substrate or both. The line to Class 204 must be followed as between Class 427, Class 204, and Class 148. Moreover, if metal casting, fusion bonding, machining, or working is involved in the combination, placement goes to Class 148 only if the heat treatment is a significant heat treatment as defined in the Class 148 definition, "A. Metal Casting, Metal Fusion Bonding, etc., above." A combination of a metal working step proper for one of the metal working classes and ion implantation for coating purposes will be proper for Class 148. See particularly subclass 239 of Class 148 for ion implantation of a metal substrate according to these distinctions. See also the Class 427 definition "Search Class" notes.

SEE OR SEARCH THIS CLASS, SUBCLASS:

22, see the notes for amplification of statement G of the Class Definition. 33, see the notes for amplification of statement H of the Class Definition.

95, see the notes for amplification of statement A in the Class Definition, see the notes under subclass of this class.

100, see the notes for amplification of statement B in the Class Definition.

194, see the notes for amplification of statement E of the Class Definition.

206, see the notes for amplification of statement C of the Class Definition.

240, see the notes for amplification of statement D of the Class Definition.

400, see the notes for amplification of statement F of the Class Definition.

REFERENCES TO OTHER CLASSES

SEE OR SEARCH CLASS

29, Metal Working, appropriate subclasses for processes having combined operations involving metal working, machining, metal fusion bonding, or casting class and treating not provided for in the metal working, machining, welding, or casting classes. Since Class 29 is a residual metal treating class and Class 148 is also a residual metal treating class, the relationship established makes Class 148 superior in all cases wherein significant heat treatment as defined in "A. Metal Casting, Metal Fusion Bonding, etc." above, first paragraph, is included. However, Class 29 is also a generic mechanical assembly class. See Notes to the Class Definition, (2) Note of the Class 29 definition, (7) Note under Class 29,

592, and the Class 29, subclass 428, definition. Wherein Class 29 mechanical assembly is involved, placement in Class 148 as original is proper over Class 29, if significant heat treatment as described in "A. Metal Casting, Metal Fusion Bonding, etc." above is included. In all other situations, mechanical assembly operations remain in Class 29. The combination of reactive coating or chemical heat removing (e.g., flame-cutting, etc.) or burning (i.e., oxidizing) to remove a portion of a metal workpiece, with a Class 29 metal working, machining, fusion bonding, casting, or mechanical assembly operation goes as an original to Class 148. (See Lines With Other Classes and Within This Class, "Metal Casting, Metal Fusion Bonding, etc.," above.) 72, Metal Deforming, appropriate subclasses for processes of deforming metal by working that involve the use of heat. Class 148 is superior to Class 72, if significant heat treatment is present before, after, or during the deforming operation. Significant heat treatment is defined under the first paragraph of "A. Metal Casting, Metal Fusion Bonding, etc." above See Lines With Other Classes and Within This Class, Relationship To Combination Classes, "With Heat Treatment", paragraph (c) of the Class 72 definition. (See Lines With Other Classes and Within This Class, "Metal Casting, Metal Fusion Bonding, etc.," above.)

117, Single-Crystal, Oriented-Crystal, and Epitaxy Growth Processes; Non-Coating Apparatus Therefor, for processes and non-coating apparatus for growing therein-defined

single-crystal of all types of materials, including metal, alloy, or intermetallic single-crystal (except those proper for the class of Metal Founding). Class 117 is proper for metal, alloy, or intermetallic single-crystal growing in any physical state, including solid phase recrystallization. Class 117 is proper for metal, alloy, or intermetallic single-crystal growing and such combined with perfecting operations for the growing step, except that Class 148 provides for single-crystal growing combined with a subsequent step of heat treatment (which herein includes controlled cooling) when the purpose of the heat treatment (or controlled cooling) is to modify the internal physical structure or chemical property of a metal, alloy, or intermetallic material. When the subsequent heat treatment (or controlled cooling) merely operates on the single-crystallinity, such as stress or strain annealing or to remove point defects, the combined process is proper for Class 117; when the subsequent heat treatment (or controlled cooling) operates to effect significant metal, alloy, or intermetallic material heat treatment (or controlled cooling) purposes, such as solutionizing, homogenizing, or precipitation hardening, then the combined process is proper for Class 148. Class 117 provides for simultaneous or prior perfecting operations combined with single-crystal growing. See Class 117 definition, section C, (4) Note, for discussion of perfecting operations. (See Lines With Other Classes and Within This Class, "Chemical Coating, Cleaning, Etching, etc.," above.)

134, Cleaning and Liquid Contact With Solids, appropriate subclasses for process of metal cleaning and pickling, per se, Combinations with a Class 148 operation go as original to Class 148. (See Lines With Other Classes and Within This Class, "Chemical Coating, Cleaning, Etching, etc.," above.)

156, Adhesive Bonding and Miscellaneous Chemical Manufacture, for adhesive bonding and chemical etching. Combinations of adhesive bonding or chemical etching with treatment of metal to modify or maintain the internal physical structure or chemical properties of metal go as original in Class 148. (See Lines With Other Classes and Within This Class, "Chemical Coating, Cleaning, Etching, etc.," above.)

164, Metal Founding, appropriate subclasses for processes of casting molten metal. (See Lines With Other Classes and Within This Class, above.)

204, Chemistry: Electrical and Wave Energy, appropriate subclasses for processes of electrocoating or sputter-coating that result in a metal layer being formed or in metal being electrocoated by another material and combinations of electrocoating or sputter-coating with other chemical treating operations that (1) involve preparatory treatment of metal substrates including heat-treatment which if claimed alone would be proper for Class 148 and (2) post-treatment solely of the electrocoated or sputter-coated layer including heat-treatment which if claimed alone would be proper for

Class 148. However, if the subsequent treatment modifies the original substrate or a combination of the original substrate and the electrocoated or sputter-coated layer, placement goes elsewhere.

Thus, Class 148 takes as original in combination with an electrocoating or sputter-coating step only processes of post-treating electrocoated or sputter-coated article or stock having an original substrate which is post-treated and having present therewith a nonelectrocoated or nonsputter coated solid or semi-solid metal portion or layer to modify the internal physical structure (i.e., microstructure) or chemical properties of metal. In combinations, including electrocoating or sputter-coating which have post-treatments, that also include metal casting, fusion bonding, machining, or working; it is necessary to have significant heat treatment as defined in Class 148, Lines With Other Classes and Within This Class, "A. Metal Casting, Metal Fusion Bonding, etc." above before placement as original in Class 148. Combinations that involve reactive coating as defined in Class 148, subclasses 240+, and a Class 204 electrocoating or sputter-coating operation go to Class 204.

Carburizing or nitriding of metal operations as defined in Class 148, subclasses 206+, if combined with a Class 204 operation go in Class 148 as original regardless of the order of the treatment and whether or not the coating or substrate is treated.

Since Class 148 is superior to Class 204, if claims are present which independently are classifiable in both classes, placement goes as original to Class 148.

(1) Note. Interdiffusion of the electrocoated or sputter-coated layer occurring during the coating operation or during the post-treatment operation is proper for Class 204 if limited to the interfacial region between the coating and the substrate as a perfecting of the bond between the coating and substrate. If the electrocoated or sputter-coated layer is completely melted in the post-treatment operation to perfect the bonding of the coating, this is proper for Class 204. If multiple electrocoated or sputter-coated regions are interdiffused to the extent of completely alloying with loss of layer identity, this is proper for Class 204. However, if the coating is completely interdiffused into a metal substrate to completely alloy, leaving no identifying layer on the substrate, placement goes to Class 148. (See Lines With Other Classes and Within This Class, above.) 205, Electrolysis: Processes, Compositions Used Therein, and Methods of Preparing the Compositions, particularly subclasses for processes of electrocoating of metal. (See Lines With Other Classes and Within This Class, above.)

219, Electric Heating, appropriate subclasses for processes of electric heating of metal for metal fusion bonding, machining, or working of metal and for processes of heating

metal, per se. If the Class 219 metal fusion bonding or working of metal is combined with significant heat treatment of metal as hereinabove defined, placement goes to Class 148. Lacking a step of metal fusion bonding, machining, or working of metal, an electric heating to perform an operation falling under the Class 148 definition will go to Class 148. Class 219 includes processes utilizing an arc, plasma, laser, or other electrically generated heat to cut metal. In general, the combination of electric heat cutting and chemical-heat removing or burning of metal will go to Class 148. However, an exception evolved in Class 219 wherein there is a simultaneous chemical-heat removing or burning and arc-cutting in which air or oxygen assisted the cutting (see Class 219,

69.1, (1) Note. Surface melting of a solid or semi-solid metal workpiece for purposes other than metal fusion bonding, and consistent with the Class 148 definition, are provided for in Class 148, even if by electric heating. (See Lines With Other Classes and Within This Class, "Metal Casting, Metal Fusion Bonding, etc.," above.)

228, Metal Fusion Bonding, appropriate subclasses for processes of metal fusion bonding or welding of metal. A combination of metal fusion bonding with a separate step involving significant heat treatment as hereinabove defined will go to Class 148. Thus, a subsequent step of heat treating to perfect the solid fusion bond left by the fusion bonding step as, for example, by diffusion or by tempering goes to Class 148. However, nominal annealing with no mention of the annealing temperature remains with Class 228. Combinations of metal fusion bonding and a separate step of surface melting of metal which is distinct and nonpreparatory to the fusion bonding step go to Class 148. Combinations of reactive coating of metal or chemical-heat removing (i.e., flame-cutting) or burning of metal with metal fusion bonding go to Class 148. Combinations of high frequency vibration in a separate step for purposes of changing microstructure and metal fusion bonding go to Class 148. (See Lines With Other Classes and Within This Class, "Metal Casting, Metal Fusion Bonding, etc.," above.)

427, Coating Processes, for processes of coating, per se. (See Lines With Other Classes and Within This Class and Within This Class, above.)

445, Electric Lamp or Space Discharge Component or Device Manufacturing, appropriate subclasses for processes of producing an assembled electric lamp or space discharge device wherein final manufacturing steps involve Class 148 heating or Class 148 coating treatment of solid metal electrodes or filaments within the completely assembled device, in which case a cross-reference is placed in Class 148. However, any Class 148 treatment of a metal electrode, per se, goes as an original in Class 148, regardless of intended use in an electric lamp or space discharge device. Thus, carburizing, decarburizing, or hardening of a metal

electrode or metal filament, per se, goes in Class 148 as original. (See Lines With Other Classes and Within This Class, "Metal Casting, Metal Fusion Bonding, etc.," above.)

502, Catalyst, Solid Sorbent, or Support Therefor: Product or Process of Making, for processes of treating metal for purposes of enhancing it's catalytic function or to make it more durable for catalytic operation even if a class 148 operation is involved. However, if heat treatment is involved to modify or maintain the microstructure or chemical properties of solid or semi-solid metal, a cross-reference to Class 148 is mandatory. (See Lines With Other Classes and Within This Class, "Chemical Coating, Cleaning, Etching, etc.," above.)

508, Solid Anti-Friction Devices, Materials Thereof, Lubricant or Separant Compositions for Moving Solid Surfaces and Miscellaneous Mineral Oil Compositions,100, 109 for inter alia materials used to make solid anti-friction devices or articles, which material contain a lubricant as a permanent part thereof, whether by permanent coating, impregnation into the interstices thereof, or by being part of the composition.

GLOSSARY:

AGING OR AGEING Also termed precipitation hardening or strengthening. A process whereby the hardness/strength of a metal alloy may be increased by subjecting a supersaturated solid solution to elevated temperature to precipitate out a secondary phase containing the solute. Aging may also be manifested as a spontaneous increase in hardness at room temperature. Aging for a longer time than that corresponding to maximum hardness at the particular temperature is termed overageing. Aging after or during straining is known as strain aging. Maraging steels are a specific group of high nickel (i.e., greater than ten percent Nickel), low carbon martensitic steels which can be fabricated while in a comparatively ductile martensitic condition and later strengthened by aging treatment.

AMORPHOUS

A term signifying a lack of regular crystalline order, much like the absence of long-range crystalline order in glass.

ANNEALING

A single thermal heat treatment wherein the heating of a metal workpiece to a temperature results in improved formability.

AUSTEMPERING

A procedure that involves preliminary quenching of austenized

metal to a temperature in the lower bainite range, usually in a molten salt bath, holding at this temperature until transformation is complete, and quenching or air cooling to room temperature. If desired, a lower hardness level may be produced by including an additional tempering step.

AUSTENIZING

A process of heating to an elevated temperature within the austenitic range.

BLUEING

A process of forming a protective oxide coating on ferrous metal. CARBURIZING

A process wherein a metal substrate is treated with an externally supplied source of carbon resulting in the carburization of the metal by chemical reaction or diffusion.

CASE HARDENING

A term most often applied to carburizing or nitriding processes which result in a hardened surface on the workpiece.

MALLEABLEIZING

A process applied to cast irons whereby the combined carbon in the as-cast microstructure is graphitized to form temper carbon. When combined with decarburization of the surface, the resulting product is termed white-heart malleable iron.

MARTEMPERING

A process which involves preliminary quenching of austenized metal to a temperature just above the Ms temperature and holding until the temperature is equalized throughout the metal, followed by air cooling through the martensite transformation range and subsequent reheating to produce tempered martensite of the desired strength level.

NITRIDING

A process wherein a metal substrate is treated with an externally supplied source of nitrogen resulting in an increased nitrogen content of the metal by chemical reaction or diffusion.

NORMALIZING

A process of heating the metal above it's critical temperature range and cooling in air thereby establishing a fine uniform grain size and improving microstructural uniformity.

PATENTING

A continuous process consisting of heating the metal to a temperature well above the upper critical temperature, then rapidly cooling through the critical temperature at a comparatively rapid rate to a predetermined elevated temperature, the cooling step being commonly effected in a fused metallic bath.

PRECIPITATION HARDENING

See definition for ageing above.

RECRYSTALLIZATION

A thermal treatment of previously worked metal to effect an equiaxed microstructure through the nucleation of strain free grains and the gradual consumption of the worked matrix by the growth of these grains.

SOLUTION TREATING

A process whereby an alloy system possessing decreasing solute solidity with temperature is treated to dissolve said solute in the parent phase. Subsequent quenching results in solute supersaturation and thus places the metal alloy in a condition for age hardening. Also applied to heating a multi-phase metal alloy to an elevated temperature to dissolve one or more phases.

STRESS RELIEVING OR STRESS RELIEF ANNEALING

The heating of metal to a comparatively low temperature to relieve microstructural strain induced by working.

TEMPERING Involves the heating of previously quenched or normalized metal alloy to an elevated temperature, and then cooling under suitable conditions to obtain the desired mechanical properties.