Classifications

• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C26/00—Coating not provided for in groups C23C2/00 - C23C24/00
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B24—GRINDING; POLISHING
  • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
  • B24B1/00—Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B24—GRINDING; POLISHING
  • B24C—ABRASIVE OR RELATED BLASTING WITH PARTICULATE MATERIAL
  • B24C1/00—Methods for use of abrasive blasting for producing particular effects; Use of auxiliary equipment in connection with such methods
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D7/00—Electroplating characterised by the article coated
  • C25D7/10—Bearings
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
  • F16C33/02—Parts of sliding-contact bearings
  • F16C33/04—Brasses; Bushes; Linings
  • F16C33/06—Sliding surface mainly made of metal
  • F16C33/12—Structural composition; Use of special materials or surface treatments, e.g. for rust-proofing
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
  • F16C33/02—Parts of sliding-contact bearings
  • F16C33/04—Brasses; Bushes; Linings
  • F16C33/06—Sliding surface mainly made of metal
  • F16C33/12—Structural composition; Use of special materials or surface treatments, e.g. for rust-proofing
  • F16C33/122—Multilayer structures of sleeves, washers or liners
  • F16C33/125—Details of bearing layers, i.e. the lining
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
  • F16C33/02—Parts of sliding-contact bearings
  • F16C33/04—Brasses; Bushes; Linings
  • F16C33/06—Sliding surface mainly made of metal
  • F16C33/14—Special methods of manufacture; Running-in
• • G—PHYSICS
  • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
  • G21C—NUCLEAR REACTORS
  • G21C19/00—Arrangements for treating, for handling, or for facilitating the handling of, fuel or other materials which are used within the reactor, e.g. within its pressure vessel
  • G21C19/02—Details of handling arrangements
  • G21C19/10—Lifting devices or pulling devices adapted for co-operation with fuel elements or with control elements
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C2204/00—Metallic materials; Alloys
  • F16C2204/02—Noble metals
  • F16C2204/04—Noble metals based on silver
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C2204/00—Metallic materials; Alloys
  • F16C2204/40—Alloys based on refractory metals
  • F16C2204/44—Alloys based on chromium
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C2204/00—Metallic materials; Alloys
  • F16C2204/52—Alloys based on nickel, e.g. Inconel
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C2220/00—Shaping
  • F16C2220/60—Shaping by removing material, e.g. machining
  • F16C2220/70—Shaping by removing material, e.g. machining by grinding
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C2223/00—Surface treatments; Hardening; Coating
  • F16C2223/02—Mechanical treatment, e.g. finishing
  • F16C2223/06—Mechanical treatment, e.g. finishing polishing
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C2223/00—Surface treatments; Hardening; Coating
  • F16C2223/02—Mechanical treatment, e.g. finishing
  • F16C2223/08—Mechanical treatment, e.g. finishing shot-peening, blasting
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C2223/00—Surface treatments; Hardening; Coating
  • F16C2223/30—Coating surfaces
  • F16C2223/70—Coating surfaces by electroplating or electrolytic coating, e.g. anodising, galvanising
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E30/00—Energy generation of nuclear origin
  • Y02E30/30—Nuclear fission reactors

Definitions

• a method of producing a metallic surface capable of withstanding prolonged lubricant-free frictional contact with another surface comprises the steps of polishing the surface of the metal to a mirror-smooth condition by conventional techniques, removing a surface layer of the metal to a determined depth such as to eliminate the afore-mentioned heterogeneous layer resulting from the polishing operations, and then depositing a metal coating.
• the initial step of the process may comprise a series of conventional grinding and buflin-g operations and should be sufficiently thorough to reduce the surface asperities and other irregularities to dimensions less than about 10 to 16 microinches, ie. 0.00025 to 0.00040 mm. as tested by means of a diamond-tip roughness-meter for example.
• Such a degree of smoothness can be obtained by means of any of various types of rectifying machines currently available, and is possibly supplemented by a series of buffing steps, preferably in the presence of water.
• the next step of the process of the invention is to remove a surface layer of the polished metal, preferably by sand-blasting, the abrasive particles being projected in a stream of pure water at high velocity.
• the third step may comprise coating, preferably electrocoating with a suitable metal.
• the second step of the process of the invention which comprises the removal of the heterogeneous layer produced by grinding.
• fine sand-blasting is preferably used for this purpose, using abrasive sand particles in an approximate range of sizes of from 2 to 100 microns, preferably with a major proportion of particles about microns in size.
• the sand blast is projected onto the metal surface in a stream of pure water at high velocity, e.g. about 300 meters per second, normally to the surface.
• the abrasive particles when applied in this manner possess sufficient kinetic energy to remove any broken-down and loosely-bonded grains of metal and compounds in the unstable heterogeneous layer.
• the outlined blasting procedure avoids unwanted temperature elevation.
• this blasting step should be conducted under conditions of strict metallic asepsis, i.e. so as to avoid introducing metallic inclusions into the treated surface comprising metals differing in nature from the constituent metal of the surface undergoing treatment.
• the presence of such foreign metal inclusions would be liable to cause oxidations through galvanic effects.
• the desired metallic asepsis is obtained by performing the sand-blasting treatment in an enclosure and With all the components of the sand-blasting apparatus used, including said enclosure, the container for abrasive material, and the sand-blasing conduits and nozzles, all being made from suitable plastic materials.
• the sand-blasting operation is continued for a time that should be determined in each case by test, sufficient to ensure the full removal of the heterogeneous layer.
• the healthy, homogeneous metal surface thus obtained is then washed with distilled water, and dried in filtered air, and metal-coated in the next step of the process of the invention.
• the metal coating may be deposited by any suitable means, electrolytic, chemical, or electrochemical in character. Electrolysis in a solid medium, as presently described, is preferred because it avoids the risk of introducing hydrogen inclusions as might be the case if an ordinary electrolysis bath were used. Such hydrogen inclusions would impart fragility to the metal coating.
• the part is manipulated under conditions of strict cleanliness.
• the part being treated is preferably connected to negative polarity so as to constitute the cathode.
• a graphite anode is used, cased in a cotton envelope impregnated with the electroplating solution used.
• the assembly comprising the graphite anode and its cotton envelope is continuously reciprocated past the part being treated so as to ensure a uniform deposition throughout the surface to be coated.
• the coating metal applied to the prepared surface of the part is selected to have a very low friction coefficient.
• the metal coating comprises two or more coatings of different metals, successively deposited.
• an initial or base layer of one metal may be electrodeposited by the procedure described above, and the resulting base coating subjected to a mild buffing action limited to the removal of any sharp points that may have been formed by electrical point effects liable to arise during electrolysis.
• the bufiing may be performed by means of a fine-grained cloth lubricated with pure water.
• the metals used in the coating operations should ing with the underlying metal as a result of the electromoreover be selected so as to be capable of strong bonddeposition process.
• the metal coated part is then preferably exposed to a diffusing heat treatment.
• the treatment involves heating the part to within the diffusion range of the coating metal used, e.g. about 250 C. Where the outer coating is gold or silver, in a non-oxidizing atmosphere. This treatment brings about a diffusion of the coating metal between the grains and enhances the final surface condition.
• the metal surface treatment of the present invention is applicable to a wide variety of mechanical components designed for prolonged lubricant-free operation in service.
• the invention was applied to the components of a pressure-gas ram actuator forming part of machinery in a nuclear plant which was to operate at elevated temperature in radioactive surroundings without possibility of lubrication.
• the engaging surfaces of the relatively movable parts of the actuator assembly in contact with plastic seal-rings were treated in accordance with the invention, using chrome as the outer coating.
• the mating surfaces of guide rings engaging the chrome-plated actuator parts were similarly treated according to the invention, using silver as the outer coating metal.
• the invention was applied to a push-rod used to transmit linear displacements, slidable within a bore and cooperative with annular sliding seal members.
• the surface of the rod was treated according to the invention, with chromium as the outer coating metal.
• the other mating bore surface was similarly treated with silver as the outer coating metal.
• silver and gold may be used as the outer coating metals respectively.
• a method for surface treating metallic parts designed to allow for an unalterable fitting during static or dynamic contact with other metallic pieces comprising the following phases:
• a process as set forth in claim 1 wherein said first phase consists in bringing the surface of each piece to a state of polish whose roughness has a value of about to 16 micro inches.
• a process as set forth in claim 1 wherein there is applied successively upon one of said surfaces a layer of nickel and a layer of chromium and upon another surface a layer of gold and a layer of silver.

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• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Metallurgy (AREA)
• Materials Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Physics & Mathematics (AREA)
• Electrochemistry (AREA)
• Plasma & Fusion (AREA)
• High Energy & Nuclear Physics (AREA)
• Other Surface Treatments For Metallic Materials (AREA)
• Joining Of Glass To Other Materials (AREA)

Applications Claiming Priority (1)

Publications (1)

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ID=8794633

Family Applications (1)

Country Status (6)

Cited By (5)

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Citations (5)

Family Cites Families (1)

• 1963
  • 1963-01-14 FR FR921321A patent/FR1461335A/fr not_active Expired
• 1964
  • 1964-01-11 DE DEC31854A patent/DE1294779B/de active Pending
  • 1964-01-11 ES ES0295239A patent/ES295239A1/es not_active Expired
  • 1964-01-13 NL NL6400172A patent/NL6400172A/xx unknown
  • 1964-01-13 US US337167A patent/US3420755A/en not_active Expired - Lifetime
  • 1964-01-14 BE BE642474A patent/BE642474A/xx unknown

Patent Citations (5)

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