Classifications

• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • 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
  • C23C8/10—Oxidising
• • 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
  • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
  • C23C18/02—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/12—All metal or with adjacent metals
  • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
  • Y10T428/12771—Transition metal-base component
  • Y10T428/12861—Group VIII or IB metal-base component
  • Y10T428/12944—Ni-base component
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/12—All metal or with adjacent metals
  • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
  • Y10T428/12771—Transition metal-base component
  • Y10T428/12861—Group VIII or IB metal-base component
  • Y10T428/12951—Fe-base component
  • Y10T428/12972—Containing 0.01-1.7% carbon [i.e., steel]

Definitions

• ABSTRACT OF THE DISCLOSURE A process for producing a surface-treated steel plate high in the anticorrosiveness, particularly adapted as a material for making cans, on the principle of the thermodecomposing plating, wherein the steel plate is coated with an aqueous solution containing nitrate and/or acetate of Ni as the main component thereof and of other metals such as Cr, Mn, Zn and Al as selective components and then heated at a certain range of temperature so as to cause the thermodecomposing reaction to cause thereby a strong film containing metallic nickel and at least one metal oxide to form on the surface of the steel plate.
• This invention relates to a method of making surfacetreated steel plates by thermodecomposing plating.
• tin As well known, as a material for making cans, a tinplated steel plate is used most today. However, tin has such problems that it is expensive, is not endurable to the use at a high temperature, is weak against corrosion in the atmosphere and further becomes black depending on the contents in case it is made a can. Furthermore, tin is so short as a resource in the world that its supply is unstable. As a result in the world that its support is unstable.
• metal-plated surface-treated steel plates including a tin-plated steel plate
• a material for making cans it is usual to coat the metal-plating layer with well known lacquers of various kinds as, for example, an epoxy resin series paint for the necessity to prevent the metal-plating layer from being corroded and the metal ions from being melted-out by such contents in the can as, for example, a beverage, liquor, oil or fat.
• a metal-plated surface-treated steel plate the following conditions are required that not only it should be high in the antirusting property in the atmosphere but also, in case it is coated with a lacquer and is then dipped in the above described corrosive liquid, the lacquer coating film should not peel off, and moreover it should not interfere with the can-manufacturing operations, for instance, it should be easy to solder and mold.
• An object of the present invention is to provide surfacetreated steel plates which are so high in the anticorrosiveness that they .can sufiiciently serve in place of tin-plated steel plates, particularly novel and economic steel plates to be used as material for manufacturing cans, generally called as tin-free steel plate and other steel plates to be used as materials for automobiles, constructions and toys.
• the present invention is to provide methods which are characterized by the following features: that is, a method for obtaining surface-treated steel plate having an excellent anticorrosiveness wherein an aqueous solution of nitrate and/or acetate of Ni is applied on the surface of a steel plate previously subjected to a surface-cleaning treatment and is then heated in a nonoxidative gas atmosphere so as to cause the thermodecomposing reaction to thereby form a film containing metallic nickel on the surface of the steel plate, and a method for forming a further improved film, that is, a method for obtaining surface-treated steel plate having an excellent anticorrosiveness wherein an aqueous solution of nitrate and/or acetate of Ni with the addition of one or more of nitrates and acetates of Cr, Mn and Zn is applied on the surface of a steel plate previously subjected to a surface-cleaning treatment and is then heated in a nonoxidative gas atmosphere so as to cause the
• the present invention is particularly very economical because it is possible to utilize a heating cycle of annealing conditions for the thermodecomposing reaction, and the method of the present invention is therefore very high in practical value.
• the thus obtained treated film is not only excellent in the anticorrosive activity but is also very ex.- cellent in the paint adhesiveness and mechanical workability. Therefore, the present invention is particularly adapted as a method of making steel plates for making cans.
• the method which makes the foundation of the present invention is to form a very thin film of metallic nickel on the surface of a steel plate by applying an aqueous solution, for example, of nickel nitrate to coat the said surface of the steel plate and heating it in a reductive or inert nonoxidative atmosphere so as to cause the thermodecomposing reaction of the treating solution and the reduction (complete or partial) of nickel nitrate to metallic nickel.
• an aqueous solution for example, of nickel nitrate
• Nickel nitrate or nickel acetate which is an essential component of the treating aqueous solution of the present invention is used alone or as mixed.
• any other Ni compound (particularly oxide) than this has a difficulty in the anticorrosiveness, paint adhesiveness and workability of the treated film and therefore should be avoided in the method of the present invention.
• the aqueous solution containing an Ni-salt prepared as described above shall be called a treating solution.
• a treating solution some of such treating solutions are difficult to uniformly apply to coat steel plates.
• an improvement can be obtained by adding a proper amount of such surface active agent as, for example, a nonionic active agent.
• Ni ions are to be contained in an amount of 0.5 to 1 g./l. or preferably 1 to 20 g./l.
• later described Cr+++ ions are less than 20 g./l. or preferably g./l.
• Al ions are less than g./l.
• Zn ions are less than 40 g./l. or preferably less than 10 g./l.
• Mn++ ions are less than 20 g./l. or preferably less than 10 g./l.
• a nitrate or acetate of Mg, Ca or K may be added in an amount of about 1 g./l.
• the appearance after the heat-treatment may have transparency of such a degree as will not substantially impair the luster of the cold-rolled steel plate or may have light tone of such a degree as can be barely recognized with the naked eye (that is, the metal thickness may be less than In or, if possible, about 0.1 or less).
• the above described treating solution is applied and is then quickly heated to cause a thermodecomposing reaction at a temperature of 200 to 750 C. in a furnace of a gas atmosphere of such nonoxidative gas in which, for example, the H content is 2 to 20% and the main component of the rest is N as DX or NX gas used as a brightly annealing gas so that a strong metallic nickel film may be formed.
• a gas atmosphere of such nonoxidative gas in which, for example, the H content is 2 to 20% and the main component of the rest is N as DX or NX gas used as a brightly annealing gas so that a strong metallic nickel film may be formed.
• the content of H in the gas atmosphere is less than 2%, the Ni salt is so hard to reduce that there is formed an undesirable film, because, the film having metallic nickel becomes lusterless and blackish.
• the content of H of more than 20% is a great loss to the economy.
• the above described nonoxidative gas may contain a slight amount of carbon dioxide, carbon monoxide or water.
• the heating atmosphere must not be oxidative by containing oxygen in such a degree as will have a bad influence on the reduction of the salt of nickel to metallic nickel, because otherwise the salt of nickel applied on the surface of a steel plate may not be reduced to metallic nickel of a required amount within the time of the annealing condition and may remain as nickel oxide on the surface of the steel plate, which does not suit with the object of the present invention.
• thermodecomposition When the heating temperature is less than 200 C., no effective thermodecomposition takes place. On the contrary, when it is more than 750 C., there are produced undesirable results that all the metallic nickel produced by the thermodecomposition will alloy with the iron base to form a hard film which is not only low in the adhesiveness but also low in the anticorrosiveness, and further even mechanical properties of the steel plate itself, which is to be treated, are often impaired thereby.
• the surface film obtained by this method is thought to be a two-layer film high in the anticorrosiveness, consisting of an Fe-Ni alloy in the lower layer and metallic nickel in the upper layer.
• the present inventors have succeeded in developing an improved method of forming on the surface of a steel plate a film which is more excellent than the above described film.
• This film is thought to be formed of two layers, wherein the lower layer is made of an Fe-Ni alloy and the upper layer is a mixture of oxides of Cr, Mn and Zn and metallic nickel, of which the mixture, however, is mainly composed.
• the improved method is that, wherein an aqueous solution (which shall be called a treating solution with additive for the convenience of the explanation hereinafter) obtained by adding one or more of nitrate and acetates of Cr, Mn arid Zn to a nitrate and/ or acetate of Ni is applied to coat the surface of a steel plate and is heated in a non-oxidative gas atmosphere furnace to form a film consisting of one or more of oxides of Cr, Mn and Zn and metallic nickel.
• the above-mentioned treating solution with additive may be prepared by adding one or more of carbonates, oxalates and hydroxides of Cr, Mn and Zn to an aqueous solution of Ni nitrate and/or acetate.
• any of methods adopted when applying the abovementioned treating solution such as the spraying method, roller-coating method and dipping method, may be likewise used. If necessary, also a surface active agent may be further added.
• the heating can be carried out under exactly the same conditions and in the same manner, that is, in a temperature range of 200 to 750 C. in a furnace of a non-oxidative gas atmosphere in which, for example, the H content is 2 to 20% and the rest is mostly N
• the thus obtained film is higher in the anticorrosiveness than in the case of the above mentioned treating solution composed of the Ni salt only.
• thermodecomposition in a temperature range of from 200 to 750 C. in a furnace of a nonoxidative gas atmosphere, in which the H content is 2 to 20%, there can be formed on the surface of a steel plate a very thin film which has been proved to be all the more improved No.
• the method of the present invention can provide cheaply a steel plate having a strong inactive film, just like the surface of a stainless steel, which is particularly suitable as a material for manufacturing cans therefrom because of being high in the anticorrosiveness and excellent in the paint adhesiveness.
• Example 1 A cold-rolled steel plate of a thickness of 0.26 mm., which had been cold-Worked by a well 'known method, that is, by using a continuous strip rolling apparatus, but had not yet been annealed, was subjected to a well known pretreatment, for example, such surface adjustments as alkali-defatting and sulfuric acid-pickling, was then dipped in an aqueous solution of nickel nitrate or nickel acetate so that nickel salt might be deposited on the surface, was immediately thereupon heated at a temperature of 600 C.
• a well known pretreatment for example, such surface adjustments as alkali-defatting and sulfuric acid-pickling
• the samples Nos. 1, 2 and 3 in the below-mentioned performance test comparison table are steel plates having a film composed of metallic nickel prepared by the above-mentioned method respectively.
• a referential sample The same cold-rolled steel plate as in Example 1 was defatted with an alakli and pickled with sulfuric acid, was then coated with a treating solution prepared by adding one or more of chromium acetate, manganese nitrate and zinc nitrate into an aqueous solution of nickel acetate or nickel nitrate by using a roller and was then immediately heated at a temperature of 600 C. in a brightly annealing gas atmosphere of an H content of 10%, the rest being N to form a film.
• the samples Nos. 4 to 8 in the above-mentioned performance test comparison table were steel plates prepared by the above-mentioned process.
• the film optained by applying a treating solution containing one or more of Cr, Mn and Zn salts in addition to an Ni salt has performances more excellent than of the film by Example 1. That is, they showed no rusting in 4 to 10 months in the rusting test by indoor exposure and were very high in the corrosion resistance below the coating film in a carbonic acid beverage after being coated with a lacquer.
• Example 3 A cold-rolled esteel plate of a thickness of 0.26 mm. which had been cold-worked by a well known method, for example, by using a continuous strip rolling apparatus, thereafter alkali-defatted, sulfuric acid-pickled and then annealed in a reductive atmosphere was once more surface-treated with alkali-defatting and sulfuric acid-pickling, was then dip-coated with a treating solution prepared by adding one or more of chromium acetate, manganese nitrate and zinc nitrate into an aqueous solution of a mixture of nickel nitrate and aluminium nitrate and was then immediately heated at a temperature of 250 C. in a heated gas atmosphere of an H content of 6%, the rest being N to form a film.
• a treating solution prepared by adding one or more of chromium acetate, manganese nitrate and zinc nitrate into an aqueous solution of a mixture of nickel nitrate and aluminium nit
• a method of imparting anti-corrosive properties to surface-treated steel plates comprising applying to the surface of a steel plate an aqueous solution consisting essentially of at least one compound selected from the group consisting of nitrates and acetates of Cr, Mn and Zn in admixture with at least one compound selected from the group consisting of a nitrate and acetate of Ni to coat the surface thereof said steel plate having been previously subjected to a surface-cleaning pretreatment and then heating the thus-coated steel plate in a nonoxidative gas atmosphere to cause a thermodecomposing reaction to form a film containing metallic nickel and at least one oxide selected from the group consisting of oxides of Cr, Mn and Zn.
• a method of imparting anti-corrosive properties to surface-treated steel plates comprising applying to the surface of a steel sheet an aqueous solution consisting essentially of at least one compound selected from the group consisting of nitrates and acetates of Cr, Mn and Zn in admixture with at least one compound selected from the group consisting of a nitrate and acetate of Ni and further containing at least one compound selected from the group consisting of a nitrate and acetate of Al to coat the surface thereof, said steel plate having been previously subjected to a surface-cleaning pretreatment and then heating the thus-coated steel plate in a nonoxidative gas atmosphere to cause a thermodecomposing reaction to 8 form a film containing metallic nickel, an oxide of aluminum and at least one oxide selected from the group consisting of oxides of Cr, Mn, and Zn.
• a method of imparting anti-corrosive properties to surface-treated steel plates comprising applying to the surface of a steel plate an aqueous solution consisting essentially of at least one compound selected from the group consisting of nitrates and acetates of Cr, Mn and Zn in admixture with at least one compound selected from the group consisting of a nitrate and acetate of Ni containing 0.5 to g./l. of Ni ions whereby less than 20 g./l. of Cr+++, less than 40 g./l. of Zn ions and less than 20 g./l.
• Mn ions are present in the solution and further containing at least one compound selected from the group consisting of a nitrate and acetate of Al so that the content of Al ions is less than 20 g./l. to coat the surface of the steel plate, said steel plate having been previously subjected to a surface-cleaning pretreatment and then heating the thus coated steel plate in a nonoxidative gas atmosphere to cause a thermodecomposing reaction to form a film containing metallic nickel, an oxide of aluminum and at least one oxide selected from the group consisting of oxides of Cr, Mn, and Zn.
• a method of imparting anti-corrosive properties to surface-treated steel plates comprising applying to the surface of a steel plate an aqueous solution consisting essentially of at least one compound selected from the group consisting of nitrates and acetates of Cr, Mn and Zn in admixture with at least one compound selected from the group consisting of a nitrate and acetate of Ni containing 1 to 20 g./l. of Ni ions whereby less than 10 g./l. of Cr+++, less than 10 g./l. of Zn ions and less than 10 g./l.
• Mn ions are present in the solution and further containing at least one compound selected from the group consisting of a nitrate and acetate of Al so that the content of Al ions may be less than 10 g./l. to coat the surface of the steel plate, said steel plate having been previously subjected to a surface-cleaning pretreatment and then heating the thus coated steel sheet in a nonoxidative gas atmosphere to cause a thermodecomposing reaction to form a film containing metallic nickel, an oxide of aluminum and at least one oxide selected from the group consisting of oxides of Cr, Mn, and Zn.
• a method of imparting anti-corrosive properties to surface treated steel plates according to claim 2 wherein the pH of said treating aqueous solution is 3 to 4 and wherein the thickness of the film formed by the coating treatment is less than i 10.

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• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• General Chemical & Material Sciences (AREA)
• Chemical Treatment Of Metals (AREA)
• Heat Treatment Of Sheet Steel (AREA)
• Laminated Bodies (AREA)
• Other Surface Treatments For Metallic Materials (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=26371461

Family Applications (1)

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Cited By (7)

• 1970
  • 1970-04-23 CA CA080902A patent/CA920037A/en not_active Expired
  • 1970-04-24 GB GB1977270A patent/GB1307591A/en not_active Expired
  • 1970-04-27 FR FR7015301A patent/FR2040300A1/fr active Pending
  • 1970-04-27 US US32439A patent/US3677797A/en not_active Expired - Lifetime

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