WO2014156205A1 - Palier à roulement pour prévention de la corrosion électrique - Google Patents

Palier à roulement pour prévention de la corrosion électrique Download PDF

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Publication number
WO2014156205A1
WO2014156205A1 PCT/JP2014/050047 JP2014050047W WO2014156205A1 WO 2014156205 A1 WO2014156205 A1 WO 2014156205A1 JP 2014050047 W JP2014050047 W JP 2014050047W WO 2014156205 A1 WO2014156205 A1 WO 2014156205A1
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WIPO (PCT)
Prior art keywords
ceramic
sprayed coating
outer ring
rolling bearing
ceramic sprayed
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Ceased
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PCT/JP2014/050047
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English (en)
Japanese (ja)
Inventor
志向 虻川
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Tocalo Co Ltd
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Tocalo Co Ltd
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Priority to CN201480016798.7A priority Critical patent/CN105051240B/zh
Publication of WO2014156205A1 publication Critical patent/WO2014156205A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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    • 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
    • C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
    • C23C4/18—After-treatment
    • 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
    • C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
    • C23C4/04—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the coating material
    • C23C4/10—Oxides, borides, carbides, nitrides or silicides; Mixtures thereof
    • C23C4/11—Oxides
    • 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
    • C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
    • C23C4/12—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the method of spraying
    • C23C4/134—Plasma spraying
    • 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
    • F16C19/00—Bearings with rolling contact, for exclusively rotary movement
    • F16C19/52—Bearings with rolling contact, for exclusively rotary movement with devices affected by abnormal or undesired conditions
    • 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
    • F16C33/30—Parts of ball or roller bearings
    • F16C33/58—Raceways; Race rings
    • F16C33/62—Selection of substances
    • 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
    • F16C33/30—Parts of ball or roller bearings
    • F16C33/58—Raceways; Race rings
    • F16C33/64—Special methods of manufacture
    • 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
    • F16C19/00—Bearings with rolling contact, for exclusively rotary movement
    • F16C19/02—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows
    • F16C19/04—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for radial load mainly
    • F16C19/06—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for radial load mainly with a single row or balls
    • 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
    • F16C2206/00—Materials with ceramics, cermets, hard carbon or similar non-metallic hard materials as main constituents
    • F16C2206/40—Ceramics, e.g. carbides, nitrides, oxides, borides of a metal
    • F16C2206/42—Ceramics, e.g. carbides, nitrides, oxides, borides of a metal based on ceramic oxides
    • F16C2206/44—Ceramics, e.g. carbides, nitrides, oxides, borides of a metal based on ceramic oxides based on aluminium oxide (Al2O3)
    • 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
    • F16C2223/42—Coating surfaces by spraying the coating material, e.g. plasma spraying

Definitions

  • the present invention relates to a rolling bearing, and more particularly to a rolling bearing for preventing electric corrosion in which electric corrosion caused by electric current generated in an electric motor of a railway vehicle or the like is prevented by coating a ceramic spray coating.
  • a rolling bearing provided with a metal outer ring and a metal inner ring arranged concentrically with the outer ring via a rolling element on the radially inner side of the outer ring as a bearing for a rotating shaft of an electric motor of a railway vehicle, etc. Is commonly used.
  • a current generated by the electric motor or the like flows through an outer ring, a rolling element, and an inner ring.
  • the current flowing through the rolling bearing sparks at the contact surface between the rolling elements and the inner and outer rings, and electric corrosion occurs on the outer ring, the rolling elements, and the inner ring that form a current path. Electrical corrosion not only degrades the performance of rolling bearings, but also causes a reduction in life.
  • the outer surface of the outer ring of the rolling bearing that contacts the housing may be covered with an insulating material.
  • a ceramic material is suitable, and in order to coat with the ceramic material, a ceramic film is formed on the outer surface of the outer ring of the rolling bearing by a thermal spraying method.
  • Patent Document 1 and Patent Document 2 describe an electric corrosion prevention rolling bearing in which the outer surface of the outer ring of the rolling bearing is roughened and a ceramic sprayed coating of 0.15 to 0.45 mm is formed on the surface. Yes.
  • a rolling bearing in which a ceramic sprayed coating made of gray alumina containing aluminum oxide and titanium oxide is formed on the outer surface of the outer ring with a predetermined thickness (Patent Document 3).
  • a rolling bearing is known in which a ceramic sprayed coating having alumina as a main component and titanium oxide content of 0.01 to 0.2% by weight is formed on the outer surface of an outer ring (Patent Document 4).
  • the particle size of the ceramic powder for forming the ceramic spray coating is 10 to 50 ⁇ m.
  • Patent Document 5 a ceramic sprayed coating having a porosity of 2 to 6% is formed on the outer surface of the outer ring and further filled with an organic sealant.
  • the surface of the outer ring attached to the housing is coated with a ceramic coating layer and two metal layers thereon.
  • Patent Document 7 describes a rolling bearing in which the outer surface of the outer ring of the rolling bearing is roughened to Ra of 1.0 to 3.0 ⁇ m and a ceramic film is formed on the roughened surface.
  • the outer surface of the outer ring is roughened to form a ceramic sprayed coating having a film thickness of 0.15 mm to 0.45 mm. If the film is formed, it is not possible to obtain a sufficient manufacturing cost reduction effect. In addition, due to the influence of the film thickness, the film peels off due to the shear stress that occurs between the outer ring of the rolling bearing and the mechanical strength due to the residual stress inside the film under the environment where the temperature difference is large. There is a risk of damage such as cracks. If only the film thickness of the ceramic sprayed coating is reduced, not only the insulating property is lowered but also the coating is easily damaged.
  • Patent Document 4 In the rolling bearings described in Patent Document 4 in which the particle size of the ceramic powder is 10 to 50 ⁇ m and in Patent Document 5 in which the ceramic sprayed coating is filled with an organic sealing agent to suppress variation in insulation resistance, ceramic spraying is performed. Since the film thickness is about 0.4 mm, the cost is high, and in addition, the adhesion between the outer ring and the ceramic spray coating is low.
  • Patent Document 6 having a three-layer structure composed of a ceramic spray coating and a metal layer is expensive because it requires a step for providing the metal layer.
  • Patent Document 7 In the rolling bearing of Patent Document 7 in which the outer surface of the outer ring of the rolling bearing is roughened to Ra: 1.0 to 3.0 ⁇ m, the adhesion is obtained, but the film thickness is large and the same as in Patent Document 1 and the like. There are problems such as high cost. In addition, there is also a drawback that insulation performance is insufficient and electrolytic corrosion occurs in an environment where a high current flows, leading to a short life.
  • the present invention can greatly reduce the manufacturing cost, is difficult to be damaged even in various environments, and has high adhesion and sufficient insulation performance. It aims at providing the rolling bearing for prevention.
  • a rolling bearing for preventing electric corrosion includes a metal outer ring, a metal inner ring that is concentrically disposed via the outer ring and a plurality of rolling elements and is relatively rotatable, and an outer ring of the outer ring.
  • a ceramic sprayed coating for preventing electrolytic corrosion formed by a plasma spraying method on the surface, and the outer surface of the outer ring has a surface roughness Ra: 0.5 ⁇ m to 2.0 ⁇ m.
  • the aluminum oxide and titanium oxide are used as the main components, and the aluminum oxide content is 98.0 wt% to 99.5 wt% and the titanium oxide content is 0.5 wt%.
  • the ceramic sprayed coating is sealed with an organic resin, the thickness of the ceramic sprayed coating is 50 ⁇ m to 100 ⁇ m, and the volume resistivity of the ceramic sprayed coating is A galvanic corrosion preventing rolling bearing, which is a 10 13 ⁇ cm ⁇ 10 16 ⁇ cm.
  • the ceramic sprayed coating is made of a material mainly composed of aluminum oxide and titanium oxide, the film forming efficiency during the spraying is high, and the film can be formed at low cost. Since the aluminum oxide content in the ceramic spray coating is 98.0 wt% to 99.5 wt%, and the titanium oxide content is 0.5 wt% to 2 wt%, Higher insulation performance can be maintained than that of a material mainly composed of normal aluminum oxide and titanium oxide, and a volume resistivity of 10 13 ⁇ cm to 10 16 ⁇ cm can be achieved.
  • the outer surface of the outer ring coated with the ceramic sprayed coating has a surface roughness Ra: 0.5 ⁇ m to 2.0 ⁇ m, high adhesion to the ceramic sprayed coating can be obtained.
  • the film thickness of the ceramic spray coating is 50 ⁇ m to 100 ⁇ m, which greatly reduces the manufacturing cost.
  • a rolling bearing for preventing electric corrosion includes a metal outer ring, a metal inner ring arranged concentrically through the outer ring and a plurality of rolling elements, and relatively rotatable, and an outer surface of the inner ring. And a ceramic sprayed coating for preventing electrolytic corrosion formed by a plasma spraying method.
  • the surface roughness of the outer surface of the inner ring is Ra: 0.5 ⁇ m to 2.0 ⁇ m
  • the ceramic sprayed coating is: It is made of a material mainly composed of aluminum oxide and titanium oxide.
  • the content of aluminum oxide is 98.0 wt% to 99.5 wt%, and the content of titanium oxide is 0.5 wt%.
  • the ceramic sprayed coating is sealed with an organic resin, the thickness of the ceramic sprayed coating is 50 ⁇ m to 100 ⁇ m, and the volume resistivity of the ceramic sprayed coating is 1 A galvanic corrosion preventing rolling bearing, which is a 13 ⁇ cm ⁇ 10 16 ⁇ cm.
  • the ceramic sprayed coating is made of a material mainly composed of aluminum oxide and titanium oxide, the film forming efficiency during the spraying is high, and the film can be formed at low cost. Since the aluminum oxide content in the ceramic spray coating is 98.0 wt% to 99.5 wt%, and the titanium oxide content is 0.5 wt% to 2 wt%, Higher insulation performance can be maintained than that of a material mainly composed of normal aluminum oxide and titanium oxide, and a volume resistivity of 10 13 ⁇ cm to 10 16 ⁇ cm can be achieved. Since the surface roughness of the outer surface of the inner ring covered with the ceramic spray coating is Ra: 0.5 ⁇ m to 2.0 ⁇ m, high adhesion to the ceramic spray coating can be obtained.
  • the film thickness of the ceramic sprayed coating is 50 ⁇ m to 100 ⁇ m, which greatly reduces the manufacturing cost.
  • the shear stress generated with the inner ring of the rolling bearing in a usage environment with a large temperature difference the residual inside the coating The mechanical strength is not easily lowered by the influence of stress, and damage such as peeling or cracking of the film can be prevented.
  • the surface roughness of the ceramic sprayed coating after the finishing treatment after the sealing treatment is Ra: less than 1 ⁇ m and the skewness Rsk to less than 0.
  • the surface roughness after the finishing treatment is Ra: less than 1 ⁇ m, and the skewness Rsk, which is a rough indication of surface irregularities, is less than 0, so there are few protrusions on the surface. Therefore, the electric field concentration occurring on the surface when a current flows can be reduced, and the dielectric breakdown can be remarkably improved.
  • the ceramic sprayed coating is preferably formed by spraying ceramic powder having an average particle size of 3 ⁇ m to 15 ⁇ m. If the average particle size is too small, the fluidity of the ceramic powder during film formation is lowered and stable supply cannot be achieved, and the thickness tends to be non-uniform. When the average particle size is too large, a portion where the film is formed without being completely melted is formed, and the film is excessively porous so that it becomes difficult to fill with the sealing agent, and the insulating performance is deteriorated.
  • the dielectric breakdown voltage per unit film thickness of the above ceramic sprayed coating is adjusted to 35 kV / mm or more, even if a high current flows through the rolling bearing, the dielectric breakdown of the ceramic sprayed coating does not occur and durability Can be significantly increased.
  • the film formation efficiency at the time of thermal spraying is high, and the film thickness of the film is thin, so that the manufacturing cost can be greatly reduced.
  • the titanium oxide content is low, high insulation performance can be maintained.
  • the surface roughness of the outer surface of the outer ring or inner ring is reduced, high adhesion with the film can be obtained.
  • the ceramic spray coating is thin, it is difficult for mechanical strength to decrease due to the effects of shear stress between the outer ring and inner ring or residual stress inside the coating, and damage caused by cracking or peeling of the coating should not be caused. Can be.
  • FIG. 1 is a cross-sectional view of a rolling bearing for preventing electrolytic corrosion according to an embodiment of the present invention in which a ceramic sprayed coating is formed on an outer ring. It is sectional drawing of the rolling bearing for electrolytic corrosion prevention which concerns on other embodiment which formed the ceramic sprayed coating in the inner ring
  • FIG. 1 is a cross-sectional view of a rolling bearing 1 for preventing electric corrosion according to an embodiment of the present invention.
  • the rolling bearing 1 for preventing electric corrosion is a ball bearing using balls as rolling elements, and is a ring-shaped metal outer ring 2 and a ring-shaped metal that is arranged concentrically with the outer ring 2 and is relatively rotatable.
  • the inner ring 3 is mainly composed of a made inner ring 3, a ring-shaped cage 4 arranged between the outer ring 2 and the inner ring 3, and a plurality of rolling elements 5 held by the cage 4.
  • this invention is not limited to this embodiment, It applies to the rolling bearing for an electric corrosion prevention provided with another shape, a form, or another member. Examples of other electric corrosion prevention rolling bearings include a tapered roller bearing and a cylindrical roller bearing.
  • An outer ring side raceway surface 2a having a circular arc shape is formed on the inner periphery of the outer ring 2, and outer ring side small diameter portions 2b and the like are formed on both sides of the outer ring side raceway surface 2a.
  • An inner ring side raceway surface 3a having a circular arc shape is formed on the outer periphery of the inner ring 3, and inner ring side small diameter portions 3b and the like are formed on both sides of the inner ring side raceway surface 3a.
  • the cage 4 has a plurality of pocket portions 4a in the circumferential direction, and a metallic and spherical rolling element 5 is rotatably held in each pocket portion 4a.
  • the plurality of rolling elements 5 roll on the outer ring side raceway surface 2 a and the inner ring side raceway surface 3 a, and the rolling element 5 moves in the same direction as the rotation direction of the inner ring 3.
  • the cage 4 that holds the plurality of rolling elements 5 also moves in the same direction as the rolling elements 5.
  • the electric corrosion prevention rolling bearing 1 is mainly applied to a rolling bearing that supports a rotating shaft of an electric motor, a generator, or an electric device of a vehicle, and current generated by the electric motor or the like generates an outer ring 2, a rolling element 5, an inner ring 3. It is a rolling bearing that prevents electric corrosion from occurring in the rolling bearing 1 for preventing electric corrosion when flowing through the shaft.
  • the outer ring 2 is fixed in contact with a housing (not shown) for attaching the rolling bearing 1 for preventing electric corrosion.
  • An insulating function is given to the entire outer surface 21 of the outer ring 2 that is a contact portion with the housing.
  • a ceramic spray coating 10 as an insulating layer is formed on the outer surface 21 of the outer ring 2.
  • the ceramic sprayed coating 10 is formed on the outer ring 2, but a similar ceramic sprayed coating may be formed on the outer surface 31 of the inner ring 3 as shown in FIG. In this case, the outer surface 31 of the inner ring 3 comes into contact with a rotating shaft (not shown).
  • Ceramic materials for forming a thermal spray coating generally, Al 2 O 3 , MgO, TiO 2 , Cr 2 O 3 , ZrO 2 , HfO 2 , SiO 2 , Y 2 O 3 , Al 2 O 3 .TiO 2 , Al 2 O 3 .SiO 2 , Al 2 O 3 .MgO, and the like are known.
  • a ceramic constituting the ceramic sprayed coating 10 of the present embodiment a material mainly composed of aluminum oxide, titanium oxide, or the like can be used.
  • gray alumina Al 2 O 3 , TiO 2
  • alumina yttria 3Al 2 O 3 ⁇ 5Y 2 O 3
  • alumina magnesia Mg ⁇ Al 2 O 4
  • alumina ⁇ silica 3Al 2 O 3 ⁇ 2SiO 2
  • gray alumina mainly composed of aluminum oxide and titanium oxide is suitable.
  • White alumina which has a high dielectric breakdown voltage and a high volume resistivity, is known as a material for a ceramic spray coating for preventing electrolytic corrosion.
  • the gray alumina (Al 2 O 3 , TiO 2 ) contains titanium oxide, which is a conductive material.
  • Gray alumina has a volume resistivity lower than that of white alumina, and a dielectric breakdown voltage is also lower than that of white alumina. .
  • film forming efficiency is an advantage of selecting gray alumina.
  • the melting point of titanium oxide (TiO 2 ) is lower than that of white alumina.
  • the titanium oxide (TiO 2 ) is more easily adhered to the metal substrate than the case where the aluminum oxide (Al 2 O 3 ) is 100%, and a uniform film is formed. Cheap. Therefore, the yield is better when gray alumina is selected, and the manufacturing cost can be reduced.
  • the main component is aluminum oxide and titanium oxide.
  • the material, gray alumina, is most preferably used.
  • the content of aluminum oxide in the ceramic sprayed coating is 98.0 wt% to 99.5 wt%, and titanium oxidation
  • the content of the product is 0.5% to 2% by weight. More preferably, the content of titanium oxide in the ceramic spray coating is 0.5 to less than 1% by weight.
  • the reason why at least titanium oxide is included in the ceramic sprayed coating is to maintain a high dielectric breakdown voltage and a high volume resistivity in consideration of the manufacturing cost as described above, and to contain a large amount of aluminum oxide. is there. That is, by reducing the content of titanium oxide to 2% by weight at the maximum, a decrease in insulation performance due to titanium oxide, which is a conductive material, is suppressed.
  • a high volume resistivity can be obtained by limiting the content of titanium oxide to such a blending ratio. Specifically, a volume resistivity of 10 13 ⁇ cm to 10 16 ⁇ cm is achieved. As a result, high insulation performance and good volume resistivity can be maintained, and at the same time, manufacturing costs can be reduced.
  • the film thickness of this embodiment is 50 ⁇ m to 100 ⁇ m, and a ceramic sprayed coating that is extremely thinner than the conventional one is formed. A more preferable range of the film thickness is 70 ⁇ m to 85 ⁇ m.
  • a strong shear stress may occur at the interface between the outer ring 2 or the inner ring 3 of the rolling bearing 1 for preventing electric corrosion and the ceramic sprayed coating 10.
  • the shear stress acts as a force to peel the ceramic sprayed coating 10 from the outer ring 2 or the inner ring 3 and causes peeling of the coating.
  • there is a residual stress due to thermal contraction that occurs during film formation inside the ceramic sprayed coating 10 and the mechanical strength may be reduced due to the influence of the residual stress, leading to a reduction in impact resistance.
  • the film thickness of the ceramic sprayed coating 10 of the present embodiment is 50 ⁇ m to 100 ⁇ m, which is an extremely thin coating, so that the shear stress is small and the coating is hardly peeled off.
  • the residual stress at the time of film formation is small, it is difficult to cause a decrease in mechanical strength. Accordingly, damage such as peeling or cracking of the film can be prevented.
  • the significance of setting the upper limit of the film thickness of the ceramic sprayed coating 10 to 100 ⁇ m is as described above, and the lower limit of the film thickness is set to 50 ⁇ m because the insulating performance cannot be maintained if the film thickness is smaller than this.
  • what is necessary is just to adjust the film-forming time, for example, in order to control the film thickness of the ceramic sprayed coating 10.
  • the ceramic sprayed coating 10 is subjected to sealing treatment to close the pores.
  • the thermal spray coating generally has pores in principle, and depending on the pore structure of the thermal spray coating, gas or liquid may permeate the coated substrate. If the sealing treatment is not performed, for example, water enters the pores and the insulating performance is lowered.
  • the sealing agent not only seals the pores of the sprayed layer, but also has a function of maintaining the adhesion of the coating after the sealing treatment.
  • the porosity of the ceramic sprayed coating 10 is set to 6% or less. When the porosity of the ceramic sprayed coating 10 is larger than 6%, the sealing agent may not be sufficiently filled, and the function of the sealing agent cannot be exhibited.
  • the porosity can be controlled by adjusting the particle size of the ceramic powder, adjusting the distance between the spray gun and the outer surfaces 21 and 31 of the outer ring 2 or inner ring 3 to be treated, and adjusting the pressure of the spraying atmosphere. it can.
  • the organic resin for sealing treatment may be any resin that has fluidity so as to enter the pores of the ceramic sprayed coating 10.
  • synthetic resins include, for example, bisphenol F type epoxy resin, bisphenol A type epoxy resin, epoxy resin such as polyglycidyl (meth) acrylate, acrylic resin, fluorine resin, urethane resin, phenol resin, xylene resin, polyester resin, unsaturated resin
  • Known synthetic resins such as polyester resins, polyamide resins, and melamine resins can be used. These can be used alone or in admixture of two or more.
  • the ceramic spray coating 10 is formed by spraying ceramic powder having an average particle size of 3 ⁇ m to 15 ⁇ m.
  • the porosity of the sprayed layer can be controlled to 6% or less, and variation in pore size can be suppressed.
  • a ceramic powder having a small particle diameter as in this embodiment, a ceramic sprayed coating 10 having small pores and uniform pore sizes can be obtained. If the pore size can be made uniform, the filling degree of the sealing agent can be improved, which is advantageous from the viewpoint of suppressing the variation in insulating performance.
  • the average particle size of the ceramic powder is desirably small, but if it is too small, the fluidity of the ceramic powder may decrease during the thermal spraying process for forming the thermal spray coating, and there is a possibility that it cannot be stably supplied. If the ceramic powder can be unevenly conveyed, the strength of the film tends to vary and the thickness tends to be non-uniform. From such a viewpoint, it is preferable to use a ceramic powder having an average particle diameter in the range of 3 ⁇ m to 15 ⁇ m, more preferably 3 ⁇ m to 12 ⁇ m. When the average particle size of the ceramic powder exceeds 15 ⁇ m, a portion where the film is formed without being completely melted is formed, and the portion becomes excessively porous so that it becomes difficult to fill the sealing agent, and the insulating performance is deteriorated.
  • the ceramic sprayed coating 10 is subjected to a sealing treatment with an organic resin and then subjected to a finishing process such as polishing, and the surface properties are controlled so that the surface roughness Ra is less than 1 ⁇ m and the skewness Rsk is less than 0. ing.
  • the arithmetic average roughness (Ra) defined in JISB0660 and the skewness Rsk defined in JISB0601 are used as indices.
  • the skewness Rsk is a physical quantity obtained by dividing the cube average of the height deviation in the reference length by the cube of the root mean square.
  • the skewness Rsk is a mathematical index that expresses the difference in surface irregularities, and serves as a standard indicating the symmetry of the irregularities on the target surface.
  • the value of the skewness Rsk is greatly influenced by the presence of a small number of protrusions and valleys remaining on the surface after polishing.
  • the skewness Rsk has a positive value when there are sharp protrusions on the surface and the convex area of the surface roughness is large, and approaches zero when the protrusions and valleys are symmetric. When the concave area of the surface roughness is large, a negative value is shown. Therefore, the outer ring 2 or the inner ring 3 of the rolling bearing 1 for preventing electric corrosion having a surface roughness Ra of less than 1 ⁇ m and a skewness Rsk of less than 0 has a surface property with very few sharp protrusions.
  • the surface properties may be controlled by adjusting the particle size of the ceramic powder during spraying.
  • the ceramic spray coating 10 is obtained by supplying ceramic powder into a heat source, spraying the ceramic powder on the outer surfaces 21 and 31 of the outer ring 2 or the inner ring 3 while heating and melting it, and depositing molten particles.
  • the ceramic powder is supplied in units of tens of thousands of pieces continuously into the heat source. As a result, particles having different flatness are deposited randomly.
  • the surface roughness (Ra) and skewness Rsk can be controlled to show the above values by using ceramic powder having an average particle size in the range of 3 ⁇ m to 15 ⁇ m as in this embodiment. .
  • the surface roughness Ra and the skewness Rsk can easily exhibit the above values by performing a sealing treatment with an organic resin.
  • the dielectric breakdown voltage per unit film thickness of the ceramic sprayed coating 10 can be 35 kV / mm or more.
  • the ceramic sprayed coating 10 is formed by any one of the atmospheric plasma spraying method, the low pressure plasma spraying method, the high-speed flame spraying method, the gas flame spraying method, the arc spraying method, the water plasma spraying method, the electric arc spraying method, and the explosion spraying method.
  • the film forming conditions by each thermal spraying method may be appropriately set according to the base material, raw material powder, film thickness, manufacturing environment, and the like.
  • the plasma spraying method is a thermal spraying method using electric energy as a heat source, and forms a film using argon or hydrogen as a plasma generation source. Since the heat source temperature is high and the frame speed is high, a high melting point ceramic material can be densely formed, which is suitable as a method for manufacturing the ceramic sprayed coating 10.
  • An example of a process for obtaining the ceramic sprayed coating 10 is to clean the outer surfaces 21 and 31 of the outer ring 2 or the inner ring 3 which is a base material, roughening the outer surfaces 21 and 31 by blasting, under The coating treatment, the thermal spraying of the ceramic sprayed coating 10 as the top coat, the sealing treatment of the surface layer of the ceramic sprayed coating 10, and the surface polishing treatment are performed in this order.
  • the undercoat process may be omitted depending on the difference in the thermal spray material, and other processes such as a preheating process may be included.
  • the undercoat improves the adhesion between the outer surfaces 21 and 31 of the outer ring 2 or the inner ring 3 and the ceramic sprayed coating 10 and prevents peeling or cracking of the coating.
  • the undercoat is not necessarily provided, and when the ceramic powder is directly sprayed onto the outer ring 2 or the inner ring 3, the spraying conditions may be employed so that the ceramic powder can be completely melted.
  • the average particle diameter of the ceramic powder may be in the range of 3 ⁇ m to 15 ⁇ m as in this embodiment, and the plasma heat source, the flight speed of the plasma particles, etc. may be optimized.
  • the ceramic sprayed coating 10 is formed on the outer surface 21 of the outer ring 2 or the outer surface 31 of the inner ring 3 of the rolling bearing 1 for preventing electric corrosion, for example, a rotating shaft of an electric motor for a railway vehicle, power generation Even if a high voltage is generated on the rotating shaft of the machine, the rolling bearing 1 that supports the rotating shaft can sufficiently exhibit the electrolytic corrosion preventing effect.
  • the ceramic sprayed coating 10 is provided in a single layer structure on the outer ring 2 or the inner ring 3 of the rolling bearing 1 for preventing electric corrosion.
  • different ceramic sprayed coatings may be formed in multiple layers, or the ceramic sprayed coating. Another metal layer may be provided on the upper layer.
  • the ceramic sprayed coating 10 is made of a material mainly composed of aluminum oxide and titanium oxide, the film formation efficiency during spraying is high and the cost is low. It is possible to form a film.
  • the aluminum oxide content in the ceramic sprayed coating 10 is 98.0 wt% to 99.5 wt%, and the titanium oxide content is 0.5 wt% to 2 wt%.
  • the surface roughness of the outer surfaces 21 and 31 of the outer ring 2 or the inner ring 3 covered with the ceramic sprayed coating 10 is Ra: 0.5 ⁇ m to 2.0 ⁇ m, high adhesion to the ceramic sprayed coating 10 is achieved. Obtainable.
  • the film thickness of the ceramic sprayed coating 10 is 50 ⁇ m to 100 ⁇ m, which has a great effect of reducing the manufacturing cost, and the shear stress generated between the outer ring 2 or the inner ring 3 of the rolling bearing in a use environment where the temperature difference is large. Further, the mechanical strength is hardly lowered due to the influence of the residual stress inside the film, and damage such as peeling or cracking of the film can be prevented. As a result, the manufacturing cost can be greatly reduced, it is difficult to damage even in various environments, it has high adhesion, and sufficient insulation performance can be exhibited.
  • the surface roughness after finishing treatment is Ra: less than 1 ⁇ m and the skewness Rsk, which is a rough indication of surface irregularities, is less than 0, there are few protrusions on the surface. Therefore, the electric field concentration occurring on the surface when a current flows can be reduced, and the dielectric breakdown can be remarkably improved.
  • composition, particle diameter of ceramic powder as a raw material, film thickness, sealing treatment, surface roughness of the substrate, surface roughness after film formation, and volume resistivity A test specimen with a different shape was manufactured and the dielectric breakdown property was evaluated. The dielectric breakdown property was evaluated by conducting a dielectric breakdown test and measuring the dielectric breakdown voltage.
  • the dielectric breakdown test method is as follows. An 80 ⁇ 80 mm aluminum foil is placed in the center on the surface on which the test piece is formed, and a voltage is applied between the aluminum foil and the back side of the test piece. The voltage was gradually increased from 0 kV until the film was broken, and the value of the voltage immediately before breaking was read. The value obtained by dividing this by the film thickness was taken as the dielectric breakdown voltage per unit thickness. As a withstand voltage tester, TOS-5101 manufactured by Kikusui Electronics Co., Ltd. was used.
  • the film thickness was measured using a standard outer micrometer M100 manufactured by Mitutoyo Corporation, and the surface roughness was measured using 2800G manufactured by Tokyo Seimitsu Surfcom Co., Ltd.
  • the volume resistivity measurement method is as follows. An 80 ⁇ 80 mm aluminum foil is placed in the center on the surface on which the test piece is formed, and a voltage is applied between the aluminum foil and the back side of the test piece. The resistance value R is calculated by dividing the voltage by the current flowing at that time.
  • the volume resistivity ⁇ is expressed as follows using the area S (8 ⁇ 8 cm) and the film thickness d (cm).
  • the apparatus used for measuring the volume resistivity is a DC withstanding voltage tester IP-701G manufactured by Musashi Intec Co., Ltd.
  • ⁇ R ⁇ (S / d) Unit: ⁇ cm
  • One side of a SS400 flat plate of 100 x 100 x 10 mm is first roughened by blasting, then ceramic spraying is performed, the surface layer on which the film is formed is subjected to sealing treatment, and finally polishing finish is performed to obtain a test piece.
  • polishing finish was performed after ceramic spraying.
  • the roughening treatment was performed by alumina grid blasting, the sealing treatment was performed by applying an epoxy sealant and then firing, and the final polishing finish was performed using a flat polishing machine. This is because the volume resistivity and dielectric breakdown voltage of the film are hardly affected by the shape of the substrate, and a more rigorous evaluation result is obtained by comparing with a flat test piece that easily obtains uniform conditions.
  • thermal spraying conditions are as follows. Thermal spraying method: plasma spraying method, current value: 600 A, argon gas flow rate: 40 NLPM, hydrogen gas flow rate: 8.5 NLPM, spraying distance: 100 mm, ladder scan (gun feed rate: 600 mm / sec, 3 mm pitch).
  • composition of each example and comparative example titanium content
  • particle diameter of ceramic powder particle diameter of ceramic powder
  • film thickness presence / absence of sealing treatment
  • surface roughness of substrate surface roughness after film formation
  • volume resistivity volume resistivity
  • dielectric breakdown test The results are shown in Table 1.
  • the result of the dielectric breakdown test is represented by a dielectric breakdown voltage (kV) and a dielectric breakdown voltage per unit thickness (kV / mm).
  • the surface roughness of the base material is the roughness after one surface of the flat plate is roughened by blasting
  • the surface roughness after film formation is that the surface layer formed is subjected to sealing treatment and polished. It is the surface roughness after finishing. In the case of no sealing treatment, it is the surface roughness after the film-formed surface is polished.
  • the dielectric breakdown voltage per unit thickness was high.
  • the dielectric breakdown voltage per unit thickness is low.
  • the film thickness is thin and the dielectric breakdown voltage per unit thickness is low.
  • Comparative Example 3 in which the sealing treatment was not performed, there was a tendency to easily include moisture in the atmosphere and to easily cause dielectric breakdown.
  • Comparative Example 4 where the substrate surface roughness was small, the adhesiveness was low, and peeling occurred during film formation.
  • Comparative Example 5 the surface roughness of the substrate is large, and the dielectric breakdown voltage per unit thickness is low. The cause is thought to be the occurrence of electric field concentration.
  • Comparative Example 6 having a large surface roughness after film formation, although the dielectric breakdown voltage per unit thickness was high, a trace of electric field concentration was observed on the film surface. In Comparative Example 7, the particle diameter of the ceramic powder was too small, the film became dense, and cracks occurred during handling. In Comparative Example 8, the surface roughness after film formation is large, and the dielectric breakdown voltage per unit thickness is low. The cause is thought to be the occurrence of electric field concentration.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Physics & Mathematics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Rolling Contact Bearings (AREA)
  • Coating By Spraying Or Casting (AREA)
  • Compositions Of Oxide Ceramics (AREA)

Abstract

L'invention concerne un palier à roulement pour prévention de la corrosion électrique (1) qui est équipé d'une bague extérieure (2) en métal, et d'une bague intérieure (3) en métal disposée avec une pluralité d'éléments roulants pour intermédiaire, et dans lequel un revêtement par projection de céramique (10) pour prévention de la corrosion électrique est formé par projection plasma sur une surface externe (21, 31) de la bague extérieure (2) ou de la bague intérieure (3). La rugosité superficielle de la surface externe (21, 31) de la bague extérieure (2) ou de la bague intérieure (3) ainsi revêtue, est telle que Ra : 0,5µm à 2,0µm; la composition du revêtement par projection de céramique (10), est telle que la teneur en oxyde d'aluminium est comprise entre 98,0 et 99,5% en masse et la teneur en oxyde de titane est comprise entre 0,5 et 2% en masse, l'épaisseur du revêtement par projection de céramique (10) est comprise entre 50µm et 100µm, la résistivité de volume du revêtement par projection de céramique (10) est comprise entre 1013Ωcm et 1016Ωcm, et la tension de claquage est supérieure ou égale à 35kV/mm.
PCT/JP2014/050047 2013-03-28 2014-01-07 Palier à roulement pour prévention de la corrosion électrique Ceased WO2014156205A1 (fr)

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EP3859178A4 (fr) * 2018-09-27 2021-11-03 NTN Corporation Palier à roulement empêchant l'électrocorrosion
US20220003273A1 (en) * 2018-09-27 2022-01-06 Ntn Corporation Anti-electrolytic corrosion rolling bearing
CN118725620A (zh) * 2024-08-15 2024-10-01 中机凯博表面技术江苏有限公司 一种小电容绝缘涂层及其制备方法和用途
WO2024251320A1 (fr) * 2023-06-07 2024-12-12 Schaeffler Technologies AG & Co. KG Bague de palier et procédé de production de celle-ci, et palier à roulement ou palier lisse ayant au moins une telle bague de palier

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JP7134639B2 (ja) 2017-03-24 2022-09-12 アクティエボラゲット・エスコーエッフ 電気絶縁層を含む転がり軸受
KR102487194B1 (ko) * 2017-12-08 2023-01-10 현대자동차 주식회사 구동모터용 베어링
CN112469354A (zh) * 2018-08-30 2021-03-09 京瓷株式会社 电手术刀用头部
CN118434702A (zh) * 2022-03-31 2024-08-02 东华隆株式会社 陶瓷热喷涂覆膜的表面处理方法和陶瓷热喷涂覆膜

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EP3859178A4 (fr) * 2018-09-27 2021-11-03 NTN Corporation Palier à roulement empêchant l'électrocorrosion
US20220003273A1 (en) * 2018-09-27 2022-01-06 Ntn Corporation Anti-electrolytic corrosion rolling bearing
US11525479B2 (en) 2018-09-27 2022-12-13 Ntn Corporation Anti-electrolytic corrosion rolling bearing
WO2024251320A1 (fr) * 2023-06-07 2024-12-12 Schaeffler Technologies AG & Co. KG Bague de palier et procédé de production de celle-ci, et palier à roulement ou palier lisse ayant au moins une telle bague de palier
CN118725620A (zh) * 2024-08-15 2024-10-01 中机凯博表面技术江苏有限公司 一种小电容绝缘涂层及其制备方法和用途

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