US3919000A - Preanneal rinse process for inhibiting rust on steel strip - Google Patents
Preanneal rinse process for inhibiting rust on steel strip Download PDFInfo
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- US3919000A US3919000A US37049773A US3919000A US 3919000 A US3919000 A US 3919000A US 37049773 A US37049773 A US 37049773A US 3919000 A US3919000 A US 3919000A
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- calcium
- ferrocyanide
- ion
- ferricyanide
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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
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F11/00—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
- C23F11/08—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids
- C23F11/18—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids using inorganic inhibitors
- C23F11/181—Nitrogen containing compounds
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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
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/68—Temporary coatings or embedding materials applied before or during heat treatment
- C21D1/70—Temporary coatings or embedding materials applied before or during heat treatment while heating or quenching
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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
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F11/00—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
- C23F11/08—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids
-
- 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
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F11/00—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
- C23F11/08—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids
- C23F11/18—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids using inorganic inhibitors
-
- 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
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F11/00—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
- C23F11/08—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids
- C23F11/18—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids using inorganic inhibitors
- C23F11/187—Mixtures of inorganic inhibitors
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Definitions
- This invention relates to a method of increasing the oxidation (i.e., rust) resistance of ferrous strip, and more particularly concerns the rinse treatment of coldrolled steel strip, prior to annealing thereof, with a soluble calcium salt or a soluble ferricyanide or ferrocyanide salt or a mixture of the calcium salt with sodium nitrite or the soluble ferricyanide or ferrocyanide, in dilute aqueous solution, to leave a thin layer of the residue from such rinse solution on the strip during annealing and subsequent storage and transit.
- a soluble calcium salt or a soluble ferricyanide or ferrocyanide salt or a mixture of the calcium salt with sodium nitrite or the soluble ferricyanide or ferrocyanide in dilute aqueous solution, to leave a thin layer of the residue from such rinse solution on the strip during annealing and subsequent storage and transit.
- the rust formation problem with steel strip dealt with by this invention is to be distinguished from the problem of preventing defects in electrolytically coated tinplate (i.e., preventing staining or dewetting of tin-coated surface) in which the steel strip is treated with a dilute aqueous rinse of a material that remains on the strip during batch annealing and is capable of reacting with carbonaceous material thereon during the batch annealing cycle.
- Cold-rolled, annealed, steel strip is subject to rusting caused by oxidation of the ferrous metal, particularly where processing water used in the mill has a high content of dissolved chlorides and/or sulfates.
- the rust formation which is more pronounced when the coiled strip is in humid environment, reduces the value of the strip for further processing and is often severe enough so that the strip must be scrapped.
- Shoemaker, in US. Pat. No. 3,668,021 offered one solution to the rust problem by disclosing the application of an aqueous suspension (dispersion) of calcium hydroxide to the strip prior to annealing.
- the disadvantages of this method stem from the water-insolubility of calcium hydroxide.
- the coldrolled steel strip is treated with an aqueous dilute rinse solution containing an effective rust-inhibiting amount of calcium ion or ferricyanide ion or ferrocyanide ion, or mixture of calcium ion with sodium nitrite or ferricyanide or ferrocyanide ion.
- aqueous dilute rinse solution containing an effective rust-inhibiting amount of calcium ion or ferricyanide ion or ferrocyanide ion, or mixture of calcium ion with sodium nitrite or ferricyanide or ferrocyanide ion.
- sodium nitrite has previously been used as a rust inhibitor for ferrous metals, but not for the purpose or in the specific utility embodied herein, and not in combination with a soluble calcium salt component.
- the components of the rinse solution of this invention are water-soluble materials, which property provides uniform coatings, simplifies the handling techniques and equipment requirements, and reduces the opportunities for residues to interefere with the temper rolling operation.
- the soluble calcium salt operable herein has a solubility in water of at least 1.88 g/liter of Ca ion, and preferably at least about 3.76 g/liter of Ca ion (at 70F) Representative of such salts are, for example,
- calcium chromate mentioned above, can be used except where the steel strip is ultimately to be coated with tin because chromate interferes with the tin-plating process.
- the soluble ferrocyanide or ferricyanide salts operable herein have a solubility in water of at least 0.94 g/liter of Fe(CN) moiety and preferably about 1.88 g/liter of ferricyanide or ferrocyanide.
- Representative of such salts are, for example,
- alkali silicate solutions for cleaning steel strip e.g., sodium orthosilicate or sodium metasilicate
- alkali silicate solutions for cleaning steel strip e.g., sodium orthosilicate or sodium metasilicate
- alkali silicate solutions for cleaning steel strip e.g., sodium orthosilicate or sodium metasilicate
- Silicates as Cleaners in the Production of Tinplate and ll. Influence of Batch Anneal", October, 1971; and the text by W. E. Hoare et al., The Technology of Tinplate, St. Martin's Press, I965.
- the strip is contacted with the rust-inhibiting rinse solution embodied herein, either by immersion or by spray application, conveniently at ambient temperature, although rinse temperatures ranging from about 50 to about 200F. may be employed, temperature of the rinse not being a critical factor.
- Said dilute aqueous rinse solution containing in admixture the dissolved calcium salt or ferricyanide or ferrocyanide, or mixture of calcium ion with the nitrite, fcrricyanide or ferrocyanide, above mentioned.
- the steel strip After the brief immersion in or spraying with said rinse solution. the steel strip is permitted to air-dry. either at ambient temperatures or at elevated temperatures. e.g.. up to about 300F., thus depositing a thin uniform film ofthe rinse solution residues thereon.
- the treated steel strip is subsequently annealed, using either conventional continuous annealing or batch annealing techniques.
- continuous annealing the treated strip is passed through an annealing oven at such a rate to provide an annealing period of approximately 20 seconds at a temperature of about 1200 to 1220F., followed by a controlled cooling cycle.
- a protective gas atmo sphere e.g., consisting of 5 percent hydrogen and 95 percent nitrogen, i.e.. a reducing gas atmosphere.
- the strip In batch annealing the strip is wound into a tight coil and subjected to the "box annealing cycle. i.e.. about ten hours at 1220F.. followed by a cooling cycle. all taking place under
- the steel strip is usually stored to await further processing. It is during this storage period that rust formation is observed on steel strip that has not been treated with an inhibiting composition.
- Test Rinse Solution Additives. Concentrations in g/liter No. Calcium Calcium Sodium Potassium Potassium Acetate Nitrate Nitrite Ferricyanide Ferrocyanide 5 0 4 7 O O O Corrosion resistance of the panels is measured by sealing the panel for 15 minutes in contact with moisture-laden air over water at 130F. The other side of the panel is at ambient room temperature (75F. The rating of good indicates a 50% reduction in rust for the panel exposed to the high himidity compared to a control panel (blank) of the same metal similarly treated and exposed. In all cases the blank panels show a heavy blush of rust. A rating ofvery good" indicates reduction. and an *excellent" rating indicates a or greater reduction in rust. The results are summarized as follows:
- a process for inhibiting rust formation on coldrolled steel strip which comprises contacting the strip, prior to annealing with an aqueous dilute rinse solution containing an effective rust-inhibiting amount of a mixture of calcium ion and sodium nitrite, the calcium ion being supplied by a soluble calcium salt having a solubility in water of at least 1.88 g/liter of Ca ion and being free of corrosion-promoting anions selected from the class consisting of sulfate and chloride, wherein the concentration of calcium ion in the solution is from about 0.25 to 3 oz. per gallon and the concentration of sodium nitrite is from about 0.13 to 3 oz. per gallon. drying the steel strip and annealing the strip in a reducing gas atmosphere.
- a process for inhibiting rust formation on coldrolled steel strip which comprises contacting the strip, prior to annealing, with an aqueous dilute rinse solution containing an effective rust-inhibiting amount of a mixture of calcium ion and ferricyanide or ferrocyanide ion, the calcium ion being supplied by a soluble calcium salt having a solubility in water of at least 1.88 g/liter ofCa ion and being free of corrosion promoting anions selected from the group consisting of sulfate and chloride. wherein the concentration of calcium ion in the solution is from about 0.25 to 3 oz. per gallon and the concentration of ferricyanide ion or ferrocyanide ion is from about 0.13 to 3 oz. per gallon, drying the steel strip and annealing the strip in a reducing gas atmosphere.
- the calcium salt is selected from the group consisting of calcium acetate, calcium benzoate, calcium butyrate, calcium chromate, calcium ferrocyanide, calcium ferricyanide, calcium formate, calcium fumarate, calcium dgluconate, calcium glycerophosphate, calcium isobutyrate.
- calcium iodide calcium lactate, calcium ormethylbutyrate.
- calcium nitrate calcium nitrite, calcium propionate.
- calcium salicylate calcium dithionate, calcium maleate and calcium valerate.
- the calcium salt is selected from the group consisting of calcium acetate, calcium benzoate, calcium butyrate, cal' cium chromate, calcium ferrocyanide, calcium ferricy- 6 lected from the group consisting of ammonium ferricyanide, ammonium ferrocyanide, calcium ferricyanide.
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- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Preventing Corrosion Or Incrustation Of Metals (AREA)
- Chemical Treatment Of Metals (AREA)
- Heat Treatment Of Strip Materials And Filament Materials (AREA)
- Electroplating Methods And Accessories (AREA)
Abstract
Cold rolled steel strip is treated, prior to annealing, with a dilute aqueous rinse solution containing soluble calcium salt or a soluble ferricyanide or ferrocyanide salt or a mixture of soluble calcium salt with sodium nitrite or soluble ferricyanide or soluble ferrocyanide. The residues of said rinses inhibit rust formation on the annealed strip during storage and transit.
Description
United States Patent n91 Yarrington [54] PREANNEAL RINSE PROCESS FOR INHIBITING RUST ON STEEL STRIP [75] Inventor: Robert Warren Yarrington, Ambler.
[73] Assignee: Pennwalt Corporation, Philadelphia.
[22] Filed: June 15. I973 [21] Appl. No; 370,497
[ 3,919,000 Nov. 11. 197;
3.039.901 6/1962 Miller 148/!4 X 3.052.575 9/1962 Crane I-lX tml-l R 3.257.159 6/1966 Zimniermann 148.6 l4 R X 3.526.552 9/l97U Church et. 1485M FOREIGN PATENTS OR APPLlCATlONS [180.951 2/1970 United Kingdonrw, [48/614 Primary Examiner-C. Lovell Attorney. Age/1!, or Fr'rmRobert G, Daneho er [5 7] ABSTRACT Cold rolled steel strip is treated. prior to annealing. with a dilute aqueous rinse solution containing soluble calcium salt or a soluble ferricyanide or ferrocyanide salt or a mixture of soluble calcium salt with sodium nitrite 0r soluble ferricyanide or soluble ferrocyanide. The residues of said rinses inhibit rust formation on the annealed strip during storage and transit.
5 Claims. N0 Drawings PREANNEAL RINSE PROCESS FOR INHIBITING RUST ON STEEL STRIP This invention relates to a method of increasing the oxidation (i.e., rust) resistance of ferrous strip, and more particularly concerns the rinse treatment of coldrolled steel strip, prior to annealing thereof, with a soluble calcium salt or a soluble ferricyanide or ferrocyanide salt or a mixture of the calcium salt with sodium nitrite or the soluble ferricyanide or ferrocyanide, in dilute aqueous solution, to leave a thin layer of the residue from such rinse solution on the strip during annealing and subsequent storage and transit. The rust formation problem with steel strip dealt with by this invention is to be distinguished from the problem of preventing defects in electrolytically coated tinplate (i.e., preventing staining or dewetting of tin-coated surface) in which the steel strip is treated with a dilute aqueous rinse of a material that remains on the strip during batch annealing and is capable of reacting with carbonaceous material thereon during the batch annealing cycle. (Brown et al., US. Pat. No. 3,632,487, and a similar treatment for chromium and chromium oxide coated strip, Brown et al. application Ser. No. 231,747, filed Mar. 3, I972, now US. Pat. No. 3,756,926.
Cold-rolled, annealed, steel strip is subject to rusting caused by oxidation of the ferrous metal, particularly where processing water used in the mill has a high content of dissolved chlorides and/or sulfates. The rust formation, which is more pronounced when the coiled strip is in humid environment, reduces the value of the strip for further processing and is often severe enough so that the strip must be scrapped. Shoemaker, in US. Pat. No. 3,668,021, offered one solution to the rust problem by disclosing the application of an aqueous suspension (dispersion) of calcium hydroxide to the strip prior to annealing. The disadvantages of this method stem from the water-insolubility of calcium hydroxide. For example, it is necessary to continuously agitate the slurry to provide a uniform dispersion of the suspended solids. In addition, the application of insoluble solids tends to give non-uniform coatings of the rust inhibiting substance which could result in localized pinpoint rusting. Another difficulty is that the residue left from treatment with an insoluble compound can be deposited on the temper rolls in the subsequent processing of the strip.
In accordance with the present invention, the coldrolled steel strip is treated with an aqueous dilute rinse solution containing an effective rust-inhibiting amount of calcium ion or ferricyanide ion or ferrocyanide ion, or mixture of calcium ion with sodium nitrite or ferricyanide or ferrocyanide ion. (Sodium nitrite has previously been used as a rust inhibitor for ferrous metals, but not for the purpose or in the specific utility embodied herein, and not in combination with a soluble calcium salt component.) The components of the rinse solution of this invention are water-soluble materials, which property provides uniform coatings, simplifies the handling techniques and equipment requirements, and reduces the opportunities for residues to interefere with the temper rolling operation. The soluble calcium salt operable herein has a solubility in water of at least 1.88 g/liter of Ca ion, and preferably at least about 3.76 g/liter of Ca ion (at 70F) Representative of such salts are, for example,
calcium acetate calcium benzoate calcium butyrate calcium chromate calcium ferrocyanide calcium ferricyanide calcium formate calcium fumarate calcium d-gluconate calcium glycerophosphate calcium isobutyrate calcium iodide calcium lactate calcium a-methylbutyrate calcium nitrate calcium nitrite calcium propionate calcium salicylate calcium dithionate calcium maleate calcium valerate Various salts of calcium whose anions are promoters of corrosion, e.g., calcium sulfate and calcium chloride, are to be avoided, as well as those likely to stain steel during annealing, such as calcium permanganate. Calcium chromate, mentioned above, can be used except where the steel strip is ultimately to be coated with tin because chromate interferes with the tin-plating process.
The soluble ferrocyanide or ferricyanide salts operable herein have a solubility in water of at least 0.94 g/liter of Fe(CN) moiety and preferably about 1.88 g/liter of ferricyanide or ferrocyanide. Representative of such salts are, for example,
ammonium ferricyanide ammonium ferrocyanide calcium ferricyanide calcium ferrocyanide magnesium ferrocyanide potassium ferricyanide potassium ferrocyanide sodium ferricyanide sodium ferrocyanide strontium ferrocyanide Before carrying out the process of this invention, it is expedient to subject the cold rolled steel strip to a conventional electrocleaning and rinsing operation, accomplished with a hot aqueous alkaline silicate solution, followed by rinsing and scrubbing. It has been observed that the process of this invention appears to provide a synergistic improvement in subsequent corrosion resistance when used in conjunction with prior electrolytic cleaning with silicates in caustic aqueous solution. The use of alkali silicate solutions for cleaning steel strip (e.g., sodium orthosilicate or sodium metasilicate) is well known and is described, for example, in the articles by L. J. Brown and J. E. Lippy, Jr. in Plating, February, I966, Silicates as Cleaners in the Production of Tinplate" and ll. Influence of Batch Anneal", October, 1971; and the text by W. E. Hoare et al., The Technology of Tinplate, St. Martin's Press, I965.
Following the foregoing cleaning operation, the strip is contacted with the rust-inhibiting rinse solution embodied herein, either by immersion or by spray application, conveniently at ambient temperature, although rinse temperatures ranging from about 50 to about 200F. may be employed, temperature of the rinse not being a critical factor. Said dilute aqueous rinse solution, containing in admixture the dissolved calcium salt or ferricyanide or ferrocyanide, or mixture of calcium ion with the nitrite, fcrricyanide or ferrocyanide, above mentioned. will usually have said components present in amounts providing from about 0.25 to 3 ounces of calcium ion per gallon of solution, and from about 0.13 to 3 ounces per gallon of sodium nitrite, or ferricyanide or ferrocyanide ion. when present. Preferred concentrations range from 0.5 to 1.5 ozjgallon of calcium ion and from 0.26 to 1.5 ozjgallon of the additional nitrite or ferrocyanide or ferricyanide ion.
After the brief immersion in or spraying with said rinse solution. the steel strip is permitted to air-dry. either at ambient temperatures or at elevated temperatures. e.g.. up to about 300F., thus depositing a thin uniform film ofthe rinse solution residues thereon. The treated steel strip is subsequently annealed, using either conventional continuous annealing or batch annealing techniques. In continuous annealing the treated strip is passed through an annealing oven at such a rate to provide an annealing period of approximately 20 seconds at a temperature of about 1200 to 1220F., followed by a controlled cooling cycle. in a protective gas atmo sphere, e.g., consisting of 5 percent hydrogen and 95 percent nitrogen, i.e.. a reducing gas atmosphere. In batch annealing the strip is wound into a tight coil and subjected to the "box annealing cycle. i.e.. about ten hours at 1220F.. followed by a cooling cycle. all taking place under a protective gas atmosphere.
Following the annealing operation, the steel strip is usually stored to await further processing. It is during this storage period that rust formation is observed on steel strip that has not been treated with an inhibiting composition.
The good results of this invention are verified by a laboratory simulation of commercial steel strip manufacture and annealing. In these tests 3 inch X 6 inch panels (about 0.009 inch thick) of cold-rolled steel strip are electrocleaned in conventional alkaline silicate (sodium orthosilicate) cleaning solution. Half of the panels (the controls) are waterrinsed, and dried. The other half are dipped in an aqueous solution of one or more rust-preventing agents at various concentrations, and then dried. The various rinse compositions are summarized as follows:
Test Rinse Solution Additives. Concentrations in g/liter No. Calcium Calcium Sodium Potassium Potassium Acetate Nitrate Nitrite Ferricyanide Ferrocyanide 5 0 4 7 O O O Corrosion resistance of the panels is measured by sealing the panel for 15 minutes in contact with moisture-laden air over water at 130F. The other side of the panel is at ambient room temperature (75F. The rating of good indicates a 50% reduction in rust for the panel exposed to the high himidity compared to a control panel (blank) of the same metal similarly treated and exposed. In all cases the blank panels show a heavy blush of rust. A rating ofvery good" indicates reduction. and an *excellent" rating indicates a or greater reduction in rust. The results are summarized as follows:
Test No.
Rating and Appearance 1 claim:
1. A process for inhibiting rust formation on coldrolled steel strip which comprises contacting the strip, prior to annealing with an aqueous dilute rinse solution containing an effective rust-inhibiting amount of a mixture of calcium ion and sodium nitrite, the calcium ion being supplied by a soluble calcium salt having a solubility in water of at least 1.88 g/liter of Ca ion and being free of corrosion-promoting anions selected from the class consisting of sulfate and chloride, wherein the concentration of calcium ion in the solution is from about 0.25 to 3 oz. per gallon and the concentration of sodium nitrite is from about 0.13 to 3 oz. per gallon. drying the steel strip and annealing the strip in a reducing gas atmosphere.
2. A process for inhibiting rust formation on coldrolled steel strip which comprises contacting the strip, prior to annealing, with an aqueous dilute rinse solution containing an effective rust-inhibiting amount of a mixture of calcium ion and ferricyanide or ferrocyanide ion, the calcium ion being supplied by a soluble calcium salt having a solubility in water of at least 1.88 g/liter ofCa ion and being free of corrosion promoting anions selected from the group consisting of sulfate and chloride. wherein the concentration of calcium ion in the solution is from about 0.25 to 3 oz. per gallon and the concentration of ferricyanide ion or ferrocyanide ion is from about 0.13 to 3 oz. per gallon, drying the steel strip and annealing the strip in a reducing gas atmosphere.
3. The process according to claim 1 wherein the calcium salt is selected from the group consisting of calcium acetate, calcium benzoate, calcium butyrate, calcium chromate, calcium ferrocyanide, calcium ferricyanide, calcium formate, calcium fumarate, calcium dgluconate, calcium glycerophosphate, calcium isobutyrate. calcium iodide, calcium lactate, calcium ormethylbutyrate. calcium nitrate. calcium nitrite, calcium propionate. calcium salicylate, calcium dithionate, calcium maleate and calcium valerate.
4. The process according to claim 2 wherein the calcium salt is selected from the group consisting of calcium acetate, calcium benzoate, calcium butyrate, cal' cium chromate, calcium ferrocyanide, calcium ferricy- 6 lected from the group consisting of ammonium ferricyanide, ammonium ferrocyanide, calcium ferricyanide. calcium ferrocyanide, magnesium ferrocyanidc. potassium ferricyanide, potassium ferrocyanide, sodium ferricyanide, sodium ferrocyanide and strontium fcrrocyanidei
Claims (5)
1. A PROCESS FOR INHIBITING RUST FORMATION ON COLDROLLED STEEL STRIP WHICH COMPRISES CONTACTING THE STRIP, PRIOR TO ANNEALING WITH AN AQUEOUS DILUTE RINSE SOLUTION CONTAINING AN EFFECTIVE RUST-INHIBITING AMOUNT OF A MIXTURE OF CALCIUM ION AN SODIUM NITRITE, THE CALCIUM ION BEING SUPPLIED BY A SOLUBLE CALCIUM SALT HAVING A SOLUBILITY IN WATER OF AT LEAST 1.88G/LITER OF CA++ ION AND BEING FREE OF CORROSION-PROMOTING ANIONS SELECTED FROM THE CLASS CONSISTING OF SULFATE AND CHLORIDE, WHEREIN THE CONCENTRATION OF CALCIUM ION IN THE SOLUTION IS FROM ABOUT 0.25 TO 3 OZ. PER GALLON AND THE CONCENTRATION OF SODIUM NITRITE IS FROM ABOUT 0.13 TO 3 OZ. PER GALLON, DRYING THE STEEL STRIP AND ANNEALING THE STRIP IN A REDUCING GAS ATMOSPHERE.
2. A process for inhibiting rust formation on cold-rolled steel strip which comprises contacting the strip, prior to annealing, with an aqueous dilute rinse solution containing an effective rust-inhibiting amount of a mixture of calcium ion and ferricyanide or ferrocyanide ion, the calcium ion being supplied by a soluble calcium salt having a solubility in water of at least 1.88 g/liter of Ca ion and being free of corrosion -promoting anions selected from the group consisting of sulfate and chloride, wherein the concentration of calcium ion in the solution is from about 0.25 to 3 oz. per gallon and the concentration of ferricyanide ion or ferrocyanide ion is from about 0.13 to 3 oz. per gallon, drying the steel strip and annealing the strip in a reducing gas atmosphere.
3. The process according to claim 1 wherein the calcium salt is selected from the group consisting of calcium acetate, calcium benzoate, calcium butyrate, calcium chromate, calcium ferrocyanide, calcium ferricyanide, calcium formate, calcium fumarate, calcium d-gluconate, calcium glycerophosphate, calcium isobutyrate, calcium iodide, calcium lactate, calcium Alpha -methylbutyrate, calcium nitrate, calcium nitrite, calcium propionate, calcium salicylate, calcium dithionate, calcium maleate and calcium valerate.
4. The process according to claim 2 wherein the calcium salt is selected from the group consisting of calcium acetate, calcium benzoate, calcium butyrate, calcium chromate, calcium ferrocyanide, calcium ferricyanide, calcium formate, calcium fumarate, calcium d-gluconate, calcium glycerophosphate, calcium isobutyrate, calcium iodide, calcium lactate, calcium Alpha -methylbutyrate, calcium nitrate, calcium nitrite, calcium propionate, calcium salicylate, calcium dithionate, calcium maleate and calcium valerate.
5. The process according to claim 4 wherein the ferricyanide or ferrocyanide ion is supplied by a salt selected from the group consisting of ammonium ferricyanide, ammonium ferrocyanide, calcium ferricyanide, calcium ferrocyanide, magnesium ferrocyanide, potassium ferricyanide, potassium ferrocyanide, sodium ferricyanide, sodium ferrocyanide and strontium ferrocyanide.
Priority Applications (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US37049773 US3919000A (en) | 1973-06-15 | 1973-06-15 | Preanneal rinse process for inhibiting rust on steel strip |
CA198,365A CA1023247A (en) | 1973-06-15 | 1974-04-29 | Preanneal rinse process for inhibiting rust on steel strip |
BR449774A BR7404497D0 (en) | 1973-06-15 | 1974-05-31 | PROCESS FOR INHIBITION OF RUST FORMATION IN COLD LAMINATED STEEL STRIP |
FR7419757A FR2233417A1 (en) | 1973-06-15 | 1974-06-07 | |
DE19742428067 DE2428067A1 (en) | 1973-06-15 | 1974-06-11 | RUST PROTECTION PROCESS FOR COLD-ROLLED STEEL STRIP |
JP6662574A JPS5035010A (en) | 1973-06-15 | 1974-06-13 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US37049773 US3919000A (en) | 1973-06-15 | 1973-06-15 | Preanneal rinse process for inhibiting rust on steel strip |
Publications (1)
Publication Number | Publication Date |
---|---|
US3919000A true US3919000A (en) | 1975-11-11 |
Family
ID=23459922
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US37049773 Expired - Lifetime US3919000A (en) | 1973-06-15 | 1973-06-15 | Preanneal rinse process for inhibiting rust on steel strip |
Country Status (6)
Country | Link |
---|---|
US (1) | US3919000A (en) |
JP (1) | JPS5035010A (en) |
BR (1) | BR7404497D0 (en) |
CA (1) | CA1023247A (en) |
DE (1) | DE2428067A1 (en) |
FR (1) | FR2233417A1 (en) |
Cited By (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0094808A1 (en) * | 1982-05-14 | 1983-11-23 | Uss Engineers And Consultants, Inc. | Method of box-annealing steel sheet to minimize annealing stickers |
US4582546A (en) * | 1982-05-14 | 1986-04-15 | United States Steel Corporation | Method of pretreating cold rolled sheet to minimize annealing stickers |
WO2014028050A1 (en) * | 2012-08-15 | 2014-02-20 | Sun Catalytix Corporation | High solubility iron hexacyanides |
US9382274B2 (en) | 2012-07-27 | 2016-07-05 | Lockheed Martin Advanced Energy Storage, Llc | Aqueous redox flow batteries featuring improved cell design characteristics |
US9559374B2 (en) | 2012-07-27 | 2017-01-31 | Lockheed Martin Advanced Energy Storage, Llc | Electrochemical energy storage systems and methods featuring large negative half-cell potentials |
US9768463B2 (en) | 2012-07-27 | 2017-09-19 | Lockheed Martin Advanced Energy Storage, Llc | Aqueous redox flow batteries comprising metal ligand coordination compounds |
US9837679B2 (en) | 2014-11-26 | 2017-12-05 | Lockheed Martin Advanced Energy Storage, Llc | Metal complexes of substituted catecholates and redox flow batteries containing the same |
US9865893B2 (en) | 2012-07-27 | 2018-01-09 | Lockheed Martin Advanced Energy Storage, Llc | Electrochemical energy storage systems and methods featuring optimal membrane systems |
US9899696B2 (en) | 2015-01-21 | 2018-02-20 | Lockheed Martin Advanced Energy Storage, Llc | Solid buffer materials for electrolyte solutions and flow batteries utilizing same |
US9899694B2 (en) | 2012-07-27 | 2018-02-20 | Lockheed Martin Advanced Energy Storage, Llc | Electrochemical energy storage systems and methods featuring high open circuit potential |
US9938308B2 (en) | 2016-04-07 | 2018-04-10 | Lockheed Martin Energy, Llc | Coordination compounds having redox non-innocent ligands and flow batteries containing the same |
US10065977B2 (en) | 2016-10-19 | 2018-09-04 | Lockheed Martin Advanced Energy Storage, Llc | Concerted processes for forming 1,2,4-trihydroxybenzene from hydroquinone |
US10164284B2 (en) | 2012-07-27 | 2018-12-25 | Lockheed Martin Energy, Llc | Aqueous redox flow batteries featuring improved cell design characteristics |
US10253051B2 (en) | 2015-03-16 | 2019-04-09 | Lockheed Martin Energy, Llc | Preparation of titanium catecholate complexes in aqueous solution using titanium tetrachloride or titanium oxychloride |
US10320023B2 (en) | 2017-02-16 | 2019-06-11 | Lockheed Martin Energy, Llc | Neat methods for forming titanium catecholate complexes and associated compositions |
US10316047B2 (en) | 2016-03-03 | 2019-06-11 | Lockheed Martin Energy, Llc | Processes for forming coordination complexes containing monosulfonated catecholate ligands |
US10343964B2 (en) | 2016-07-26 | 2019-07-09 | Lockheed Martin Energy, Llc | Processes for forming titanium catechol complexes |
US10377687B2 (en) | 2016-07-26 | 2019-08-13 | Lockheed Martin Energy, Llc | Processes for forming titanium catechol complexes |
US10497958B2 (en) | 2016-12-14 | 2019-12-03 | Lockheed Martin Energy, Llc | Coordinatively unsaturated titanium catecholate complexes and processes associated therewith |
US10644342B2 (en) | 2016-03-03 | 2020-05-05 | Lockheed Martin Energy, Llc | Coordination complexes containing monosulfonated catecholate ligands and methods for producing the same |
US10741864B2 (en) | 2016-12-30 | 2020-08-11 | Lockheed Martin Energy, Llc | Aqueous methods for forming titanium catecholate complexes and associated compositions |
US10930937B2 (en) | 2016-11-23 | 2021-02-23 | Lockheed Martin Energy, Llc | Flow batteries incorporating active materials containing doubly bridged aromatic groups |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5397912A (en) * | 1977-02-09 | 1978-08-26 | Nippon Steel Corp | Manufacture of surface active steel plate |
JPS61204392A (en) * | 1985-03-07 | 1986-09-10 | Nisshin Steel Co Ltd | Production of chromium coated stainless steel strip |
Citations (5)
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US1260740A (en) * | 1917-08-02 | 1918-03-26 | William H Allen | Treatment of iron and steel to prevent corrosion. |
US3039902A (en) * | 1958-04-15 | 1962-06-19 | Allegheny Ludlum Steel | Method of treating steel |
US3052575A (en) * | 1961-02-13 | 1962-09-04 | Inland Steel Co | Method of inhibiting corrosion |
US3257159A (en) * | 1964-01-23 | 1966-06-21 | Bayer Ag | Prevention of corrosion of wet metal articles |
US3526552A (en) * | 1966-06-02 | 1970-09-01 | Babcock & Wilcox Co | Metal treating |
-
1973
- 1973-06-15 US US37049773 patent/US3919000A/en not_active Expired - Lifetime
-
1974
- 1974-04-29 CA CA198,365A patent/CA1023247A/en not_active Expired
- 1974-05-31 BR BR449774A patent/BR7404497D0/en unknown
- 1974-06-07 FR FR7419757A patent/FR2233417A1/fr not_active Withdrawn
- 1974-06-11 DE DE19742428067 patent/DE2428067A1/en active Pending
- 1974-06-13 JP JP6662574A patent/JPS5035010A/ja active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1260740A (en) * | 1917-08-02 | 1918-03-26 | William H Allen | Treatment of iron and steel to prevent corrosion. |
US3039902A (en) * | 1958-04-15 | 1962-06-19 | Allegheny Ludlum Steel | Method of treating steel |
US3052575A (en) * | 1961-02-13 | 1962-09-04 | Inland Steel Co | Method of inhibiting corrosion |
US3257159A (en) * | 1964-01-23 | 1966-06-21 | Bayer Ag | Prevention of corrosion of wet metal articles |
US3526552A (en) * | 1966-06-02 | 1970-09-01 | Babcock & Wilcox Co | Metal treating |
Cited By (40)
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EP0094808A1 (en) * | 1982-05-14 | 1983-11-23 | Uss Engineers And Consultants, Inc. | Method of box-annealing steel sheet to minimize annealing stickers |
US4582546A (en) * | 1982-05-14 | 1986-04-15 | United States Steel Corporation | Method of pretreating cold rolled sheet to minimize annealing stickers |
US10056639B2 (en) | 2012-07-27 | 2018-08-21 | Lockheed Martin Energy, Llc | Aqueous redox flow batteries featuring improved cell design characteristics |
US9991544B2 (en) | 2012-07-27 | 2018-06-05 | Lockheed Martin Advanced Energy Storage, Llc | Aqueous redox flow batteries comprising metal ligand coordination compounds |
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US9559374B2 (en) | 2012-07-27 | 2017-01-31 | Lockheed Martin Advanced Energy Storage, Llc | Electrochemical energy storage systems and methods featuring large negative half-cell potentials |
US10707513B2 (en) | 2012-07-27 | 2020-07-07 | Lockheed Martin Energy, Llc | Aqueous redox flow batteries comprising metal ligand coordination compounds |
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US9997799B2 (en) | 2012-08-15 | 2018-06-12 | Lockheed Martin Advanced Energy Storage, Llc | High solubility iron hexacyanides |
US12009562B2 (en) | 2012-08-15 | 2024-06-11 | Lockheed Martin Energy, Llc | High solubility iron hexacyanides |
US9742021B2 (en) | 2012-08-15 | 2017-08-22 | Lockheed Martin Advanced Energy Storage, Llc | High solubility iron hexacyanides |
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US9929425B2 (en) | 2012-08-15 | 2018-03-27 | Lockheed Martin Advanced Energy Storage, Llc | High solubility iron hexacyanides |
CN104755423A (en) * | 2012-08-15 | 2015-07-01 | 洛克希德马丁尖端能量存储有限公司 | High solubility iron hexacyanides |
WO2014028050A1 (en) * | 2012-08-15 | 2014-02-20 | Sun Catalytix Corporation | High solubility iron hexacyanides |
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CN104755423B (en) * | 2012-08-15 | 2017-12-08 | 洛克希德马丁尖端能量存储有限公司 | Six cyanogen of high-dissolvability close iron |
US10374248B2 (en) | 2012-08-15 | 2019-08-06 | Lockheed Martin Energy, Llc | High solubility iron hexacyanides |
US9837679B2 (en) | 2014-11-26 | 2017-12-05 | Lockheed Martin Advanced Energy Storage, Llc | Metal complexes of substituted catecholates and redox flow batteries containing the same |
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US10316047B2 (en) | 2016-03-03 | 2019-06-11 | Lockheed Martin Energy, Llc | Processes for forming coordination complexes containing monosulfonated catecholate ligands |
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US10497958B2 (en) | 2016-12-14 | 2019-12-03 | Lockheed Martin Energy, Llc | Coordinatively unsaturated titanium catecholate complexes and processes associated therewith |
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Also Published As
Publication number | Publication date |
---|---|
DE2428067A1 (en) | 1975-01-09 |
BR7404497D0 (en) | 1975-09-23 |
FR2233417A1 (en) | 1975-01-10 |
CA1023247A (en) | 1977-12-27 |
JPS5035010A (en) | 1975-04-03 |
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Legal Events
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AS | Assignment |
Owner name: ATOCHEM NORTH AMERICA, INC., A PA CORP. Free format text: MERGER AND CHANGE OF NAME EFFECTIVE ON DECEMBER 31, 1989, IN PENNSYLVANIA;ASSIGNORS:ATOCHEM INC., ADE CORP. (MERGED INTO);M&T CHEMICALS INC., A DE CORP. (MERGED INTO);PENNWALT CORPORATION, A PA CORP. (CHANGED TO);REEL/FRAME:005496/0003 Effective date: 19891231 |