US20080041497A1 - Carburized Wire and Method for Producing the Same - Google Patents
Carburized Wire and Method for Producing the Same Download PDFInfo
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- US20080041497A1 US20080041497A1 US11/853,334 US85333407A US2008041497A1 US 20080041497 A1 US20080041497 A1 US 20080041497A1 US 85333407 A US85333407 A US 85333407A US 2008041497 A1 US2008041497 A1 US 2008041497A1
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- steel wire
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- wire
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- 238000004519 manufacturing process Methods 0.000 title claims description 3
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 142
- 239000010959 steel Substances 0.000 claims abstract description 142
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 90
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 52
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 51
- 238000000034 method Methods 0.000 claims abstract description 45
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- 230000007797 corrosion Effects 0.000 claims abstract description 41
- 229910000677 High-carbon steel Inorganic materials 0.000 claims abstract description 19
- 238000010276 construction Methods 0.000 claims abstract description 4
- 238000005255 carburizing Methods 0.000 claims description 49
- 238000010438 heat treatment Methods 0.000 claims description 36
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- 230000000171 quenching effect Effects 0.000 claims description 7
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- 238000005496 tempering Methods 0.000 claims description 5
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 3
- 239000010941 cobalt Substances 0.000 claims description 3
- 229910017052 cobalt Inorganic materials 0.000 claims description 3
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 3
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- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 229910001562 pearlite Inorganic materials 0.000 description 2
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- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
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Images
Classifications
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
- C21D9/525—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length for wire, for rods
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/06—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of rods or wires
-
- 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
- C23C12/00—Solid state diffusion of at least one non-metal element other than silicon and at least one metal element or silicon into metallic material surfaces
-
- 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
- C23C24/00—Coating starting from inorganic powder
-
- 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
-
- 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
- C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
- C23C8/08—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases only one element being applied
- C23C8/20—Carburising
- C23C8/22—Carburising of ferrous surfaces
-
- 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
- C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C8/40—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using liquids, e.g. salt baths, liquid suspensions
- C23C8/42—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using liquids, e.g. salt baths, liquid suspensions only one element being applied
- C23C8/44—Carburising
-
- 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
- C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C8/60—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using solids, e.g. powders, pastes
- C23C8/62—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using solids, e.g. powders, pastes only one element being applied
- C23C8/64—Carburising
Definitions
- This invention relates to methods for carburizing steel and specifically, for increasing the carbon content in low carbon steel wire used in tire constriction while improving corrosion resistance and rubber adherence of the steel wire during the carburization process.
- Such belts are generally comprised of patterned layers of steel wire embedded into a rubber compound to form a belt.
- the physical properties of the wire that is incorporated in the belts including, the wire's ductility, tensile and impact strength are tightly controlled to produce belts optimized for use in tires.
- other physical characteristics of wire to be used in tires are also important, including corrosion resistance and the ability of the wire to adhere to associated rubber compounds. The adhesion characteristics are especially important to ensure that the wire does not separate from the associated rubber in the belt.
- steel wire having high carbon content is used in the constriction of belts for tires.
- High carbon steel has advantageous properties of increased strength, which make it preferable for use in tire applications.
- high carbon steel is meant steel having a carbon content of approximately between 0.6% and 1.5% carbon content.
- adhesion improving agents such as cobalt, copper, or brass
- tire manufacturers may elect to incorporate adhesion improving agents into the associated rubber rather than into the wire. This method results in improved steel to rubber adherence, but also results in waste of the adhesion improving agents dispersed throughout the rubber, which are not directed solely to the points of contact between the wire and the rubber.
- the present invention addresses this problem by proposing new methods and processes for preparing high carbon steel wire for useful applications, by carburizing low carbon steel wire in order to increase the carbon content of the wire and in the same processing period carburizing the wire in the presence of suitable agents for improved corrosion resistance and rubber adherence.
- inexpensive low carbon steel wire can be turned into useful, high carbon, corrosive resistant, rubber adhering wire useful for a variety of applications.
- low carbon steel wire is carburized in the presence of carburizing agents to result in high carbon steel wire.
- low carbon steel wire is carburized into high carbon steel with a solid carburizing agent.
- low carbon steel wire is carburized into high carbon steel with a liquid carburizing agent.
- low carbon steel wire is carburized into high carbon steel with a gaseous carburizing agent.
- low carbon steel wire is carburized in the presence of additives resulting in high carbon steel wire having improved corrosion resistance.
- low carbon steel wire is carburized in the presence of additives resulting in high carbon steel wire having improved rubber adherence.
- carburized steel wire is rapidly quenched and tempered to produce steel wire useful in construction of vehicle tires.
- FIG. 2 is a depiction of the cross section of steel wire during the carburization process of the present invention.
- FIG. 3 is an image of the microstructure of a steel wire carburized according to the process taught in the present invention.
- FIG. 5 is yet another image of a steel wire carburized according to the process taught in the present invention.
- FIG. 6 is a depiction of a carburized steel wire in a quenching medium.
- FIGS. 7A-7C are images showing the microstructure of a steel wire carburized according to the process taught in the present invention and specifically Example 1 below.
- FIG. 1 depicts a length of steel wire 10 to be carburized in accordance with the processes described herein.
- the length of steel wire 10 is a length of low carbon steel wire.
- low carbon steel wire is meant steel wire having a carbon content of less than approximately 0.25%. It should be noted that steel wire 10 having any carbon content may be used in accordance with the present invention, including, but not limited to steel wire having a carbon content of between approximately 0.25% and 0.5%.
- the steel wire 10 may have a diameter (d) of between approximately 0.2 millimeters and approximately 2.0 millimeters, though wire of any diameter may be selected with sound engineering judgment.
- the relatively small diameter (d) of the steel wire 10 allows for rapid heating and cooling of the steel wire 10 , which increases the speed at which the carburization process may take place.
- the steel wire 10 may be the product of drawing steel stock through a die to reduce the diameter of the steel stock.
- the steel wire 10 may, however, be formed by any means selected with sound engineering judgment. While the present invention advocates processing steel wire, it should be noted that the present invention may be practiced on other forms of thin steel materials, including, without limitation, steel plating having a thickness of between approximately 0.2 millimeters and approximately 2.0 millimeters.
- the steel wire 10 may be placed in a vessel 15 .
- the vessel 15 may be configured to contain a carburizing agent 20 or a carrier medium (not shown) containing a carburizing agent 20 .
- the carrier medium may be the same as the carburizing agent 20 .
- the dimensions and materials of the vessel 15 may be selected in accordance with sound engineering judgment and may be may be constructed of materials suitable for withstanding the temperatures associated with the carburization process (discussed below).
- the carburizing agent 20 may be a liquid carburizing agent. It should be understood, however, that the carburization process of the present invention may occur using liquid carburizing agents, solid carburizing agents or gaseous carburizing agents.
- liquid carburizing agents include petroleum-based oils, salt baths, and synthetic mixtures, which are well known in the art.
- solid carburizing agents include carbon black and powdered graphite.
- gaseous carburizing agents include methane, propane, ethylene, acetylene and carbon monoxide.
- Other solid, liquid, and gaseous carburizing agents which are known in the art and selected with sound engineering judgment, may be used in accordance with the processes disclosed herein.
- the carburizing agent 20 may be contained in a carrier medium (not shown), which may be a solid, liquid or gaseous carrier medium.
- the carburizing agent 20 is a liquid carburizing agent. At least a portion of the steel wire 10 may be immersed in the carburizing agent 20 . In one embodiment, the steel wire 10 may be fully immersed in the carburizing agent 20 . The steel wire 10 , may be held within the vessel 15 in contact with the carburizing agent 20 by any means selected with sound engineering judgment.
- the vessel 15 may contain other agents in addition to the carburizing agent 20 .
- the vessel 15 may contain more than one carburizing agent 21 .
- the vessel 15 may contain a corrosion resist agent 22 .
- corrosion resist agent is meant materials that are known in the art to improve the corrosion resistance of steel wire. Such materials may include, but are not limited to, materials containing chrome, nickel, vanadium or titanium.
- the corrosion resist agent 22 may be selected from materials that adhere to the surface of the steel wire 10 or alternatively, from materials that diffuse into the steel wire 10 .
- the corrosion resist agent 22 may be combined with a carrier medium that is the same as the carrier medium, if any, for the carburizing agent 20 , or that is a different carrier medium.
- improved corrosion resistance of the steel wire 10 may result from the carburization process, without the addition of a separate corrosion resist agent 22 .
- the carburization process of the present invention may result in the diffusion of carbon from the carburizing agent 20 into the core of the steel wire 10 (shown in FIG. 2 ). This infusion carbon into the steel wire 10 may result in a formation of a layer of carbon dense cementite (depicted as 37 in FIGS. 3-5 ) starting at the surface of the steel wire 10 and extending toward the center of the steel wire 10 .
- the cementite layer 37 resulting from the carburization process may improve the strength of the steel wire 10 .
- the cementite layer 37 also provides a measure of improved corrosion resistance to the steel wire 10 even in the absence of additional corrosion resist agents 22 . Accordingly, improved corrosion resistance of steel wire 10 processed according to the present invention may be anticipated without additional corrosion resist agent 22 , but may be further improved by carburizing the steel wire 10 in the presence of additional corrosion resist agent 22 as described above.
- the vessel 15 may also contain a rubber adherent agent 23 .
- rubber adherent agent is meant materials that are known in the art to improve the adherence of rubber and rubber-based compounds to steel wire.
- Such rubber adherent agents 23 may include, but are not limited to materials containing cobalt and copper; however, any such agent selected with sound engineering judgment may be used.
- the rubber adherent agent 23 may be selected from materials that adhere to the surface of the steel wire 10 or alternatively from materials that diffuse into the steel wire 10 .
- the rubber adherent agent 23 may be combined with a carrier medium that is the same as the carrier medium, if any, for the carburizing agent 20 , or that is a different carrier medium.
- FIG. 1 shows a vessel 15 containing a carburizing agent 20 , corrosion resist agent 22 and rubber adherence agent 23 , it should be noted that the invention may be practiced with only a carburizing agent 20 or with a combination of a carburizing agent 20 and one of either a corrosion resist agent 22 or a rubber adherence agent 23 .
- a heating means 25 operatively coupled to the steel wire 10 for heating the steel wire 10 .
- the heating means 25 may be an induction heating means or a resistance heating means, although any other means for heating the steel wire 10 to a temperature that allows for carburization to occur may be selected with sound engineering judgment.
- the heating means 25 may by an electrical heating means, wherein electricity is conducted to and through the steel wire 10 as a means for heating the steel wire 10 .
- the electrodes 27 , 28 may be connected to an electrical source for generating electricity which is passed through the steel wire 10 .
- the heating means 25 may alternatively be an oven or furnace, which may be placed within the vessel 15 or which may be outside the vessel 15 . Any heating means 25 capable of heating the steel wire 10 to the appropriate temperature may be selected with sound engineering judgment.
- the heating means 25 is capable of heating the steel wire 10 to a temperature in excess of approximately 950° C. In an alternate embodiment, the heating means is capable of heating the steel wire 10 to a temperature of between approximately 1200° C. and 1350° C.
- FIGS. 2-5 heating the steel wire 10 in the presence of the carburizing agent 20 may result in carburization of the steel wire 10 as carbon from the carburizing agent 20 diffuses through the surface of the steel wire 10 and into the core of the steel wire 10 .
- Carburization results in an increase in the carbon content of the steel wire 10 , which, in turn, may result in the conversion of low carbon steel wire to high carbon steel wire.
- the relatively high temperatures (between approximately 1200° C.-1350° C.) reached during the carburization process may result in an increased rate of carbon diffusion from the carburizing agent into the steel wire 10 , which may result in faster processing time from low carbon content to high carbon content.
- FIGS. 3-5 are images showing a cross-section of steel wire 10 after the carburization process.
- the corrosion resist agent 22 or elements thereof may either or both affix to the surface of the steel wire 10 or diffuse into the steel wire 10 , thereby resulting in improved corrosion resistance (not shown) in the steel wire.
- the rubber adherent agent 23 or elements thereof may either or both affix to the surface of the steel wire 10 or diffuse into the steel wire 10 , thereby resulting in improved adherence between the steel wire 10 and rubber compounds as may be used in steel belts for tires.
- sufficient amounts of carburization agent 20 , corrosion resist agent 22 and rubber adherence agent 23 may be added to the vessel 15 to ensure adequate uptake of these elements to sufficiently improve the steel wire 10 to desired levels of strength, corrosion resistance, and rubber adherence.
- the steel wire 10 may be quenched in a quenching medium 35 .
- the quenching medium 35 may be any quenching medium that is selected with sound engineering judgment and may include an oil quenching medium or water. Such media 35 are well known in the art for industrial applications.
- One purpose of the quenching medium 35 is to cool the steel wire 10 quickly to a temperature of approximately lower than 200° C. and preserve the grain structure of the steel wire 10 after the carburization process.
- the carburized steel wire 10 may undergo an additional tempering process wherein the steel wire 10 is tempered or annealed to reduce the brittleness created as a result of the carburization process.
- the tempering process may involve heating and then cooling the steel wire 10 in succession, wherein the steel wire 10 is heated to temperature of between approximately 200° C. and 400° C. and then cooled to a temperature of lower than approximately 200° C. This tempering cycle of heating and cooling may be repeated. In one embodiment the tempering process may be repeated up to three times. Additional processing steps, including further reduction in the diameter of the steel wire 10 by drawing, may be conducted on the high carbon steel wire produced in accordance with the present invention.
- the carburizing experiment was performed by resistance heating wire in a machine oil.
- a 6′′ long pieces of a low carbon wire with 0.2% carbon and diameter of 2 mm was clamped between two electrodes and submerged in a stainless container with dimensions of 12′′ ⁇ 4′′ ⁇ 4′′. Heating of the wire was done by using both direct current and alternating current. After heating and cooling the wire inside the oil, it was taken out of the container and cleaned from the oil.
- Carburized samples were mounted in conductive epoxy mounts, polished, and Nital etched to reveal microstructure of the processed wire. Microstructure of the processed wires was examined in a Leica optical microscope and a Jeol scanning electron microscope.
- FIGS. 3 and 4 show the obtained microstructure comprised of pearlite and primary cementite.
- This microstructure is typical for a carbon content close to the eutectic composition of 4.3% carbon. It provides a unique combination of high strength characteristics of cementite and ductility of pearlite. Additionally, a special residue deposited at the surface provided improved steel rubber adhesion
- FIG. 7A shows a transition portion of the rolled wire between the original wire diameter (non-rolled) and a portion with a reduced diameter (rolled portion).
- FIGS. 7B and 7C show microstructures in the surface layer and in the wire core, respectively.
- Some of the carburized wires were water quenched and then annealed at 600° C. for time ranging from 30 to 120 minutes.
- As-quenched wires were brittle and cracked during wire rolling ( FIGS. 8A and 8B ).
- Annealing resulted in increased wire ductility allowing rolling without cracking.
- Obtained microstructure of the tempered wires, i.e. quenched and annealed wires represent a typical spheroidal pearlitic structure in surface layers.
- microstructure remained predominantly ferritic with some pearlitic colonies typical for low carbon steel.
Abstract
Methods are taught for processing low carbon steel wire into high carbon steel wire having improved characteristics for use in vehicle tire construction and other applications, including increased wire strength, corrosion resistance and rubber adherence. Low carbon steel wire is carburized to raise carbon content, resulting in increased strength and corrosion resistance. According to other aspects of the invention, the carburization process may occur in the presence of rubber adherence agents, which adhere to the steel wire, resulting in improved steel rubber adherence in a single processing step.
Description
- This divisional patent application claims priority from a utility patent application having Ser. No. 10/975,811, which was filed on Oct. 27, 2004.
- Not Applicable
- Not Applicable
- Not Applicable
- 1. Field of Invention
- This invention relates to methods for carburizing steel and specifically, for increasing the carbon content in low carbon steel wire used in tire constriction while improving corrosion resistance and rubber adherence of the steel wire during the carburization process.
- 2. Description of the Related Art
- The incorporation of steel belts in vehicle tires has resulted in substantial improvement in tire strength, durability, and performance. Such belts are generally comprised of patterned layers of steel wire embedded into a rubber compound to form a belt. In light of the high stresses found in tires, the physical properties of the wire that is incorporated in the belts, including, the wire's ductility, tensile and impact strength are tightly controlled to produce belts optimized for use in tires. Apart from the physical properties of the steel wire set forth above, other physical characteristics of wire to be used in tires are also important, including corrosion resistance and the ability of the wire to adhere to associated rubber compounds. The adhesion characteristics are especially important to ensure that the wire does not separate from the associated rubber in the belt.
- One component of steel that affects the physical properties of steel wire is the carbon content. Typically, steel wire having high carbon content is used in the constriction of belts for tires. High carbon steel has advantageous properties of increased strength, which make it preferable for use in tire applications. By “high carbon steel” is meant steel having a carbon content of approximately between 0.6% and 1.5% carbon content. The adhesion properties of steel wire may be improved by incorporating adhesion improving agents, such as cobalt, copper, or brass, into the wire; however, improving the wire to include these agents currently either involves purchasing more expensive processed wire at the outset or passing the wire through additional processing steps. To avoid additional processing of the wire, tire manufacturers may elect to incorporate adhesion improving agents into the associated rubber rather than into the wire. This method results in improved steel to rubber adherence, but also results in waste of the adhesion improving agents dispersed throughout the rubber, which are not directed solely to the points of contact between the wire and the rubber.
- While high carbon steel is preferable for use in tire applications, it is more expensive to acquire than low carbon steel equivalents. Moreover, steel wire used in the tire industry is often created by drawing the wire to its final diameter. High carbon steel wire is generally relatively more difficult to draw into appropriately sized wire than low carbon steel, resulting in increased manufacturing expenses. Moreover, such wire presently needs to be separately processed in order to add coatings or other agents necessary for improved corrosion resistance and rubber adherence, thereby adding additional processing steps. Tire manufacturers have included these additional costs in order to meet the specifications of their tires; however, it would be preferable to produce high carbon, corrosion resistant, rubber adhering steel wire by starting with inexpensive low carbon steel wire and raising the carbon content as well as introducing corrosion resistance and improved rubber adherence in a single processing step. In this way, material costs, processing time and the number of processing steps can be reduced without sacrificing the benefits of high carbon steel wire processed according to existing methods.
- The present invention addresses this problem by proposing new methods and processes for preparing high carbon steel wire for useful applications, by carburizing low carbon steel wire in order to increase the carbon content of the wire and in the same processing period carburizing the wire in the presence of suitable agents for improved corrosion resistance and rubber adherence. In this way, by one process, inexpensive low carbon steel wire can be turned into useful, high carbon, corrosive resistant, rubber adhering wire useful for a variety of applications.
- According to one aspect of the invention, low carbon steel wire is carburized in the presence of carburizing agents to result in high carbon steel wire.
- According to another aspect of the invention, low carbon steel wire is carburized into high carbon steel with a solid carburizing agent.
- According to yet another aspect of the invention, low carbon steel wire is carburized into high carbon steel with a liquid carburizing agent.
- According to another aspect of the invention, low carbon steel wire is carburized into high carbon steel with a gaseous carburizing agent.
- According to still another aspect of the invention, low carbon steel wire is carburized in the presence of additives resulting in high carbon steel wire having improved corrosion resistance.
- According to still another aspect of the invention, low carbon steel wire is carburized in the presence of additives resulting in high carbon steel wire having improved rubber adherence.
- According to another aspect of the invention, low carbon steel wire is carburized at a temperature of approximately 1200° C. to 1350° C.
- According to still another aspect of the invention, carburized steel wire is rapidly quenched and tempered to produce steel wire useful in construction of vehicle tires.
- Still other benefits and advantages of the invention will become apparent to those skilled in the art to which it pertains upon a reading and understanding of the following detailed description of the invention.
- The invention may take physical form in certain parts and arrangement of parts, a preferred embodiment of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof and wherein:
-
FIG. 1 is a depiction of steel wire prepared for carburization. -
FIG. 2 is a depiction of the cross section of steel wire during the carburization process of the present invention. -
FIG. 3 is an image of the microstructure of a steel wire carburized according to the process taught in the present invention. -
FIG. 4 is another image showing the microstructure of a steel wire carburized according to the process taught in the present invention. -
FIG. 5 is yet another image of a steel wire carburized according to the process taught in the present invention. -
FIG. 6 is a depiction of a carburized steel wire in a quenching medium. -
FIGS. 7A-7C are images showing the microstructure of a steel wire carburized according to the process taught in the present invention and specifically Example 1 below. -
FIGS. 8A and 8B are images showing the microstructure of a steel wire carburized according to the process taught in the present invention and specifically Example 2 below. - Referring now to the drawings wherein the showings are for purposes of illustrating a preferred embodiment of the invention only and not for purposes of limiting the same,
FIG. 1 depicts a length ofsteel wire 10 to be carburized in accordance with the processes described herein. In one embodiment, the length ofsteel wire 10 is a length of low carbon steel wire. By “low carbon steel wire” is meant steel wire having a carbon content of less than approximately 0.25%. It should be noted thatsteel wire 10 having any carbon content may be used in accordance with the present invention, including, but not limited to steel wire having a carbon content of between approximately 0.25% and 0.5%. Though the increase in carbon content produced in such higher carbon content steel wire by carburization may be proportionately reduced as compared to using low carbon steel wire, other benefits may be induced in such wire by virtue of conducting the carburization process in the presence ofcorrosion resist agents 22 or rubberadherent agents 23, in accordance with the methods taught herein. - The
steel wire 10 may have a diameter (d) of between approximately 0.2 millimeters and approximately 2.0 millimeters, though wire of any diameter may be selected with sound engineering judgment. The relatively small diameter (d) of thesteel wire 10 allows for rapid heating and cooling of thesteel wire 10, which increases the speed at which the carburization process may take place. Thesteel wire 10 may be the product of drawing steel stock through a die to reduce the diameter of the steel stock. Thesteel wire 10 may, however, be formed by any means selected with sound engineering judgment. While the present invention advocates processing steel wire, it should be noted that the present invention may be practiced on other forms of thin steel materials, including, without limitation, steel plating having a thickness of between approximately 0.2 millimeters and approximately 2.0 millimeters. - Continuing with reference to
FIG. 1 , thesteel wire 10 may be placed in avessel 15. Thevessel 15 may be configured to contain acarburizing agent 20 or a carrier medium (not shown) containing acarburizing agent 20. In one embodiment, the carrier medium may be the same as thecarburizing agent 20. The dimensions and materials of thevessel 15 may be selected in accordance with sound engineering judgment and may be may be constructed of materials suitable for withstanding the temperatures associated with the carburization process (discussed below). In the embodiment depicted inFIG. 1 , thecarburizing agent 20 may be a liquid carburizing agent. It should be understood, however, that the carburization process of the present invention may occur using liquid carburizing agents, solid carburizing agents or gaseous carburizing agents. Examples of liquid carburizing agents include petroleum-based oils, salt baths, and synthetic mixtures, which are well known in the art. Examples of solid carburizing agents include carbon black and powdered graphite. Examples of gaseous carburizing agents include methane, propane, ethylene, acetylene and carbon monoxide. Other solid, liquid, and gaseous carburizing agents, which are known in the art and selected with sound engineering judgment, may be used in accordance with the processes disclosed herein. Additionally, as noted above, thecarburizing agent 20 may be contained in a carrier medium (not shown), which may be a solid, liquid or gaseous carrier medium. - In one embodiment, depicted in
FIG. 1 , thecarburizing agent 20 is a liquid carburizing agent. At least a portion of thesteel wire 10 may be immersed in thecarburizing agent 20. In one embodiment, thesteel wire 10 may be fully immersed in thecarburizing agent 20. Thesteel wire 10, may be held within thevessel 15 in contact with thecarburizing agent 20 by any means selected with sound engineering judgment. - The
vessel 15 may contain other agents in addition to thecarburizing agent 20. For example, thevessel 15 may contain more than one carburizingagent 21. Further, thevessel 15 may contain a corrosion resistagent 22. By “corrosion resist agent” is meant materials that are known in the art to improve the corrosion resistance of steel wire. Such materials may include, but are not limited to, materials containing chrome, nickel, vanadium or titanium. The corrosion resistagent 22 may be selected from materials that adhere to the surface of thesteel wire 10 or alternatively, from materials that diffuse into thesteel wire 10. The corrosion resistagent 22 may be combined with a carrier medium that is the same as the carrier medium, if any, for thecarburizing agent 20, or that is a different carrier medium. - It should be noted that improved corrosion resistance of the
steel wire 10 may result from the carburization process, without the addition of a separate corrosion resistagent 22. The carburization process of the present invention may result in the diffusion of carbon from thecarburizing agent 20 into the core of the steel wire 10 (shown inFIG. 2 ). This infusion carbon into thesteel wire 10 may result in a formation of a layer of carbon dense cementite (depicted as 37 inFIGS. 3-5 ) starting at the surface of thesteel wire 10 and extending toward the center of thesteel wire 10. Thecementite layer 37 resulting from the carburization process may improve the strength of thesteel wire 10. Thecementite layer 37 also provides a measure of improved corrosion resistance to thesteel wire 10 even in the absence of additional corrosion resistagents 22. Accordingly, improved corrosion resistance ofsteel wire 10 processed according to the present invention may be anticipated without additional corrosion resistagent 22, but may be further improved by carburizing thesteel wire 10 in the presence of additional corrosion resistagent 22 as described above. - The
vessel 15 may also contain a rubberadherent agent 23. By “rubber adherent agent” is meant materials that are known in the art to improve the adherence of rubber and rubber-based compounds to steel wire. Such rubberadherent agents 23 may include, but are not limited to materials containing cobalt and copper; however, any such agent selected with sound engineering judgment may be used. The rubberadherent agent 23 may be selected from materials that adhere to the surface of thesteel wire 10 or alternatively from materials that diffuse into thesteel wire 10. The rubberadherent agent 23 may be combined with a carrier medium that is the same as the carrier medium, if any, for thecarburizing agent 20, or that is a different carrier medium. - While
FIG. 1 shows avessel 15 containing acarburizing agent 20, corrosion resistagent 22 andrubber adherence agent 23, it should be noted that the invention may be practiced with only acarburizing agent 20 or with a combination of acarburizing agent 20 and one of either a corrosion resistagent 22 or arubber adherence agent 23. - Continuing with reference to
FIG. 1 , there is provided a heating means 25 operatively coupled to thesteel wire 10 for heating thesteel wire 10. The heating means 25 may be an induction heating means or a resistance heating means, although any other means for heating thesteel wire 10 to a temperature that allows for carburization to occur may be selected with sound engineering judgment. In accordance with the above, the heating means 25 may by an electrical heating means, wherein electricity is conducted to and through thesteel wire 10 as a means for heating thesteel wire 10. In such an embodiment, there may be provided one ormore electrodes steel wire 10. Theelectrodes steel wire 10. The heating means 25 may alternatively be an oven or furnace, which may be placed within thevessel 15 or which may be outside thevessel 15. Any heating means 25 capable of heating thesteel wire 10 to the appropriate temperature may be selected with sound engineering judgment. - In one embodiment, the heating means 25 is capable of heating the
steel wire 10 to a temperature in excess of approximately 950° C. In an alternate embodiment, the heating means is capable of heating thesteel wire 10 to a temperature of between approximately 1200° C. and 1350° C. - Continuing with reference to
FIG. 1 , thesteel wire 10 in thevessel 15 containing thecarburizing agent 20, may be heated by the heating means 25 to a temperature of approximately between 1200° C. and 1350° C. As noted above, thevessel 15 may also contain one or more of a corrosionresistant agent 22 and a rubberadherent agent 23. The corrosion resistagent 22 or the rubberadherent agent 23 may be added to thevessel 15 while thesteel wire 10 is heated. Alternatively, the corrosion resistagent 22 or the rubberadherent agent 23 may be added to thevessel 15 before thesteel wire 10 is heated. In this way, there may be a single processing step for improving thesteel wire 10, wherein the corrosion resistance or the rubber adherence or both of thesteel wire 10 is improved in the same heating step as is used during carburization. - As shown in
FIGS. 2-5 , heating thesteel wire 10 in the presence of thecarburizing agent 20 may result in carburization of thesteel wire 10 as carbon from thecarburizing agent 20 diffuses through the surface of thesteel wire 10 and into the core of thesteel wire 10. Carburization results in an increase in the carbon content of thesteel wire 10, which, in turn, may result in the conversion of low carbon steel wire to high carbon steel wire. The relatively high temperatures (between approximately 1200° C.-1350° C.) reached during the carburization process may result in an increased rate of carbon diffusion from the carburizing agent into thesteel wire 10, which may result in faster processing time from low carbon content to high carbon content.FIGS. 3-5 are images showing a cross-section ofsteel wire 10 after the carburization process. Thecementite layer 37 is the result of the increased carbon content resulting from diffusion of carbon into the wire. As noted above, thecementite layer 37 imparts a measure of corrosion resistance to thesteel wire 10 even in the absence of other corrosion resistagents 22. Thecementite layer 37 also increases the strength of thesteel wire 10, with adeeper cementite layer 37 being related to increased strength. The carburization of thesteel wire 10 may be allowed to proceed until thecementite layer 37 is sufficiently present to impart desired strength to thesteel wire 10. - When the carburization process occurs in a
vessel 15 containing a corrosion resistagent 22, the corrosion resistagent 22 or elements thereof may either or both affix to the surface of thesteel wire 10 or diffuse into thesteel wire 10, thereby resulting in improved corrosion resistance (not shown) in the steel wire. In a similar manner, when the carburization process occurs in avessel 15 containing a rubberadherent agent 23, the rubberadherent agent 23 or elements thereof may either or both affix to the surface of thesteel wire 10 or diffuse into thesteel wire 10, thereby resulting in improved adherence between thesteel wire 10 and rubber compounds as may be used in steel belts for tires. It should be noted that sufficient amounts ofcarburization agent 20, corrosion resistagent 22 andrubber adherence agent 23 may be added to thevessel 15 to ensure adequate uptake of these elements to sufficiently improve thesteel wire 10 to desired levels of strength, corrosion resistance, and rubber adherence. - As shown in
FIG. 6 , at such time as the pertinent properties of thesteel wire 10, namely, its carbon content, corrosion resistance, and rubber adherence properties are suitably improved, thesteel wire 10 may be quenched in a quenchingmedium 35. The quenchingmedium 35 may be any quenching medium that is selected with sound engineering judgment and may include an oil quenching medium or water.Such media 35 are well known in the art for industrial applications. One purpose of the quenchingmedium 35 is to cool thesteel wire 10 quickly to a temperature of approximately lower than 200° C. and preserve the grain structure of thesteel wire 10 after the carburization process. - The carburization process of the
steel wire 10 may result insteel wire 10 having increased carbon content. The carbon content of thesteel wire 10 may be increased to a level found in high carbon steel wire (as defined above). In one embodiment, the carbon content of thesteel wire 10 may be increased from approximately less than 0.25% to approximately 1.3%. The carbon content of thesteel wire 10 may be increased to as high as approximately 4.3% as a result of the processes taught herein. Furthermore, thesteel wire 10 may be improved to include improved corrosion resistance and the rubber adherence by means of incorporation of corrosion resistagent 22 orcementite layer 37 andrubber adherence agent 23 on the surface of thesteel wire 10 or within thesteel wire 23. - While the cementite layer (shown as 37 in
FIGS. 3-5 ) of the carburizedsteel wire 10 may cause thesteel wire 10 to have increased strength, thecementite layer 37 in thesteel wire 10, also may impart an increased brittleness to thesteel wire 10. Accordingly, the carburizedsteel wire 10 may undergo an additional tempering process wherein thesteel wire 10 is tempered or annealed to reduce the brittleness created as a result of the carburization process. The tempering process may involve heating and then cooling thesteel wire 10 in succession, wherein thesteel wire 10 is heated to temperature of between approximately 200° C. and 400° C. and then cooled to a temperature of lower than approximately 200° C. This tempering cycle of heating and cooling may be repeated. In one embodiment the tempering process may be repeated up to three times. Additional processing steps, including further reduction in the diameter of thesteel wire 10 by drawing, may be conducted on the high carbon steel wire produced in accordance with the present invention. - Although the invention has been shown and described with respect to at least one embodiment, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In addition, while a particular feature of the invention may have been described above with respect to only one of several illustrated embodiments, such features may be combined with one or more other features of the other embodiments, as may be desired and advantageous for any given particular application.
- The various aspects of the invention will be appreciated more fully in light of the following illustrative examples for producing high carbon steel wire in accordance with the present invention. Although the following examples have specified steps, materials, and equipment that may be used in such a method to make high carbon steel wire, those skilled in the art will appreciate that many modifications and substitutions may be made. Accordingly, it is intended that all such modifications, alterations, substitutions, and additions be considered to fall within the spirit and scope of the invention as defined by the appended claims.
- The carburizing experiment was performed by resistance heating wire in a machine oil. A 6″ long pieces of a low carbon wire with 0.2% carbon and diameter of 2 mm was clamped between two electrodes and submerged in a stainless container with dimensions of 12″×4″×4″. Heating of the wire was done by using both direct current and alternating current. After heating and cooling the wire inside the oil, it was taken out of the container and cleaned from the oil. Carburized samples were mounted in conductive epoxy mounts, polished, and Nital etched to reveal microstructure of the processed wire. Microstructure of the processed wires was examined in a Leica optical microscope and a Jeol scanning electron microscope.
FIGS. 3 and 4 show the obtained microstructure comprised of pearlite and primary cementite. This microstructure is typical for a carbon content close to the eutectic composition of 4.3% carbon. It provides a unique combination of high strength characteristics of cementite and ductility of pearlite. Additionally, a special residue deposited at the surface provided improved steel rubber adhesion - 4″ long wires with 0.2% carbon composition and diameters ranging from 0.2 to 1.5 mm were packed with carbon black into a ceramic ladle with a cover. They were heated inside a tube furnace at temperatures ranging from 950° C. to 1350° C. and times ranging from 5 to 30 minutes. Processed samples were cleaned and metallographic samples were prepared as discussed in Example 1 above. Characterization of the obtained microstructure showed presence of cementite layer in the surface zone of the wire typical for a pro-eutectoid steel with carbon content around 1.3%. Such a cementite layer increases corrosion resistance of steel. Obtained wires were rolled in a wire rolling mill to evaluate wire processability. The strain of up to 2 was achieved without wire breaks.
FIG. 7A shows a transition portion of the rolled wire between the original wire diameter (non-rolled) and a portion with a reduced diameter (rolled portion). -
FIGS. 7B and 7C show microstructures in the surface layer and in the wire core, respectively. Some of the carburized wires were water quenched and then annealed at 600° C. for time ranging from 30 to 120 minutes. As-quenched wires were brittle and cracked during wire rolling (FIGS. 8A and 8B ). Annealing resulted in increased wire ductility allowing rolling without cracking. Obtained microstructure of the tempered wires, i.e. quenched and annealed wires, represent a typical spheroidal pearlitic structure in surface layers. In the wire core, microstructure remained predominantly ferritic with some pearlitic colonies typical for low carbon steel. - Having thus described the invention, it is now claimed:
Claims (8)
1. A method for improving steel wire for use in vehicle tire construction, the method comprising the steps of:
providing a length of steel wire having a carbon content at a first carbon level,
providing at least a first carburizing agent,
providing at least a first rubber adherence agent,
contacting the at least a first carburizing agent and the at least a first rubber adherence agent with the length of steel wire,
providing a heating means for heating the length of steel wire,
operatively coupling the heating means to the length of steel wire,
heating the length of steel wire to a first temperature, wherein the first temperature is between approximately 950° C. and 1350° C., and
heating the length of steel wire at approximately the first temperature until the carbon content of the length of steel wire is at a second carbon level, wherein the second carbon level is higher than the first carbon level.
2. The method of claim 1 , wherein the length of steel wire has a diameter of between approximately 0.2 millimeters and approximately 2.0 millimeters, and
wherein, the first carbon level of the length of steel wire is less than approximately 0.5%.
3. The method of claim 2 , wherein the first carbon level of the length of steel wire is less than approximately 0.25%, and
wherein, the second carbon level of the length of steel wire is greater than approximately 0.6%.
4. The method of claim 3 , wherein the first temperature is between approximately 1200° C. and approximately 1350° C.
5. The method of claim 4 , wherein:
the at least a first carburizing agent is selected from the group consisting of solid carburizing agents, liquid carburizing agents and gaseous carburizing agents, and
wherein the at least a first rubber adherence agent is selected from the group consisting of copper containing rubber adherence agents and cobalt containing rubber adherence agents.
6. The method of claim 4 , further comprising quenching the length of steel wire to a second temperature, wherein the second temperature is lower than approximately 200° C., and
tempering the length of steel wire.
7. The method of claim 1 , further comprising the step of providing at least a first corrosion resist agent, and
contacting the at least a first corrosion resist agent with the length of steel wire before the step of heating the length of steel wire to a first temperature.
8. A method for producing high carbon steel wire for use in vehicle tire construction, the method comprising the steps of:
providing a length of steel wire having a carbon content at a first carbon level, wherein the first carbon level of the length of steel wire is less than approximately 0.25%
providing at least a first carburizing agent,
contacting the at least a first carburizing agent with the length of steel wire,
providing a heating means for heating the length of steel wire,
operatively coupling the heating means to the length of steel wire,
heating the length of steel wire to a first temperature, wherein the first temperature is between approximately 1200° C. and 1350° C., and
heating the length of steel wire at approximately the first temperature until the carbon content of the length of steel wire is at a second carbon level, wherein the second carbon level is greater than approximately 0.6%.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/853,334 US20080041497A1 (en) | 2004-10-27 | 2007-09-11 | Carburized Wire and Method for Producing the Same |
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Application Number | Priority Date | Filing Date | Title |
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US10/975,811 US20060086430A1 (en) | 2004-10-27 | 2004-10-27 | Carburized wire and method for producing the same |
US11/853,334 US20080041497A1 (en) | 2004-10-27 | 2007-09-11 | Carburized Wire and Method for Producing the Same |
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US10/975,811 Division US20060086430A1 (en) | 2004-10-27 | 2004-10-27 | Carburized wire and method for producing the same |
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US20080041497A1 true US20080041497A1 (en) | 2008-02-21 |
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US11/853,334 Abandoned US20080041497A1 (en) | 2004-10-27 | 2007-09-11 | Carburized Wire and Method for Producing the Same |
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US (2) | US20060086430A1 (en) |
EP (1) | EP1652943A1 (en) |
CN (2) | CN1796591B (en) |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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RU2477336C1 (en) * | 2011-07-27 | 2013-03-10 | Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Донской государственный технический университет" | Metal product cementation method |
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JP6772143B2 (en) * | 2014-12-31 | 2020-10-21 | 株式会社ブリヂストン | Aminoalkoxy-modified silsesquioxane adhesive for bonding alloy steel to rubber |
FR3040911A1 (en) * | 2015-09-16 | 2017-03-17 | Michelin & Cie | PNEUMATIC COMPRISING CARCASE FRAME CABLES WITH LOW CARBON RATES |
CN114589952A (en) * | 2022-02-24 | 2022-06-07 | 江苏兴达钢帘线股份有限公司 | Tire bead steel wire and manufacturing method thereof |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4023989A (en) * | 1975-10-20 | 1977-05-17 | Monsanto Company | Method for producing corded steel wire |
US4651513A (en) * | 1984-09-24 | 1987-03-24 | N.V. Bekaert S.A. | Layered steel cord |
US5688597A (en) * | 1994-08-08 | 1997-11-18 | Sumitomo Rubber Industries, Ltd. | Tire core |
US20040069394A1 (en) * | 2000-12-27 | 2004-04-15 | Giancarlo Armellin | Reinforced tyre |
US6991687B2 (en) * | 2001-07-27 | 2006-01-31 | Surface Combustion, Inc. | Vacuum carburizing with napthene hydrocarbons |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS62142019A (en) * | 1985-12-13 | 1987-06-25 | Hitachi Metals Ltd | Manufacture of high carbon alloy fine wire |
JPH01177318A (en) * | 1987-12-30 | 1989-07-13 | Nippon Steel Corp | Manufacture of coiled spring excellent in fatigue strength |
-
2004
- 2004-10-27 US US10/975,811 patent/US20060086430A1/en not_active Abandoned
-
2005
- 2005-10-18 BR BRPI0504509-6A patent/BRPI0504509A/en not_active IP Right Cessation
- 2005-10-25 EP EP05109964A patent/EP1652943A1/en not_active Ceased
- 2005-10-27 CN CN200510118512.9A patent/CN1796591B/en not_active Expired - Fee Related
- 2005-10-27 CN CN201010163334A patent/CN101818319A/en active Pending
-
2007
- 2007-09-11 US US11/853,334 patent/US20080041497A1/en not_active Abandoned
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4023989A (en) * | 1975-10-20 | 1977-05-17 | Monsanto Company | Method for producing corded steel wire |
US4651513A (en) * | 1984-09-24 | 1987-03-24 | N.V. Bekaert S.A. | Layered steel cord |
US4651513B1 (en) * | 1984-09-24 | 1990-03-13 | Bekaert Sa Nv | |
US5688597A (en) * | 1994-08-08 | 1997-11-18 | Sumitomo Rubber Industries, Ltd. | Tire core |
US20040069394A1 (en) * | 2000-12-27 | 2004-04-15 | Giancarlo Armellin | Reinforced tyre |
US6991687B2 (en) * | 2001-07-27 | 2006-01-31 | Surface Combustion, Inc. | Vacuum carburizing with napthene hydrocarbons |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
RU2477336C1 (en) * | 2011-07-27 | 2013-03-10 | Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Донской государственный технический университет" | Metal product cementation method |
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CN101818319A (en) | 2010-09-01 |
BRPI0504509A (en) | 2006-06-27 |
EP1652943A1 (en) | 2006-05-03 |
CN1796591A (en) | 2006-07-05 |
US20060086430A1 (en) | 2006-04-27 |
CN1796591B (en) | 2011-04-13 |
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