WO2016017186A1 - Procédé de production de matériau d'acier galvanisé par immersion à chaud, et matériau d'acier galvanisé par immersion à chaud - Google Patents

Procédé de production de matériau d'acier galvanisé par immersion à chaud, et matériau d'acier galvanisé par immersion à chaud Download PDF

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WO2016017186A1
WO2016017186A1 PCT/JP2015/003869 JP2015003869W WO2016017186A1 WO 2016017186 A1 WO2016017186 A1 WO 2016017186A1 JP 2015003869 W JP2015003869 W JP 2015003869W WO 2016017186 A1 WO2016017186 A1 WO 2016017186A1
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flux
steel material
mass
hot
dip galvanized
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PCT/JP2015/003869
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English (en)
Japanese (ja)
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康人 猪原
村瀬　正次
勇 鹿毛
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Ｊｆｅスチール株式会社
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Priority to JP2015555314A priority Critical patent/JP6137339B2/ja
Priority to KR1020177002131A priority patent/KR20170024023A/ko
Priority to CN201580041381.0A priority patent/CN106661708B/zh
Publication of WO2016017186A1 publication Critical patent/WO2016017186A1/fr

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    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C23C2/022—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by heating
    • 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
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C23C2/024—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by cleaning or etching
    • 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
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/04—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor characterised by the coating material
    • C23C2/06—Zinc or cadmium or alloys based thereon
    • 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
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/34—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor characterised by the shape of the material to be treated
    • C23C2/36—Elongated material
    • C23C2/38—Wires; Tubes

Definitions

  • the present invention relates to a hot dip galvanized steel material and a method for producing the same.
  • a hot dip galvanizing bath having a Pb content of 0.10 mass% or less and a Cd content of 0.01 mass% or less, which is within the range regulated by the RoHS Directive (RoHSdirective, Restriction of Hazardous Substances Directive).
  • the present invention relates to a method for producing a hot-dip galvanized steel material with less plating defects and a hot-dip galvanized steel material when galvanizing bath is used.
  • the European Union has enforced the RoHS Directive that restricts the use of specific hazardous substances for electrical and electronic equipment.
  • This RoHS directive restricts the Pb content in the target product to 0.10 mass% or less and the Cd content to 0.01 mass% or less.
  • the RoHS Directive is a regulation outside Japan, it is necessary to respond to international regulations and to supply better products in an environment where the inclusion of environmentally hazardous substances is suppressed. Pb and Cd It is considered that products containing a large amount will tend to be avoided in the future.
  • the galvanized layer in many hot dip galvanized products still contains Pb and Cd exceeding the values regulated by the RoHS directive.
  • the Pb and Cd are derived from impurities in the hot dip galvanizing bath that is a plating raw material.
  • Pb in the hot dip galvanizing bath produces an effect of improving the wettability of the steel material surface to be plated (surface of the steel material to be plated) with respect to the molten zinc. Thereby, for example, even when the surface of the steel material to be plated is not clean or when there is an oxide layer, a galvanizing layer is easily formed.
  • the so-called “batch-dip hot dip galvanizing” performed on steel materials such as steel pipes and steel structures is different from the hot dip galvanizing treatment performed on thin steel plates.
  • the hot dip galvanizing treatment performed on a thin steel plate organic substances on the surface of the steel plate are removed and the steel plate is continuously immersed in a hot dip galvanizing bath in a reducing atmosphere. That is, a thin galvanized layer is formed on the surface of the steel sheet by contacting the molten zinc with the surface of the steel sheet in a very clean and highly active state.
  • the steel sheet Since the reducing atmosphere is present, naturally, zinc oxide or the like hardly floats on the hot dip galvanizing bath, and the steel sheet is processed in a state in which a substance that inhibits plating such as zinc oxide does not easily adhere to the steel sheet surface. Furthermore, the growth of the alloy phase may be controlled by heating. On the other hand, the hot dip galvanizing process performed with respect to steel materials is normally performed under air release. For this reason, in order to prevent oxidation of the surface of the steel material and to obtain a removal effect against the contamination of the surface of the steel material, the steel material to be plated is subjected to flux treatment and then immersed in a plating bath.
  • a pickling treatment for removing dirt such as oil on the surface of the steel material, and in some cases, a degreasing treatment is performed before the pickling treatment.
  • a steel pipe has a complicated shape unlike a steel plate, so that its effect is very insufficient at present.
  • an alloy phase is formed during immersion in the hot dip galvanizing bath, the thickness of the hot dip galvanized layer is controlled by wiping after pulling up from the hot dip galvanizing bath, and then air cooling or hot water cooling is performed. For this reason, the thickness of the galvanized layer is also from several tens of ⁇ m to several hundreds of ⁇ m or more, and is characterized by being thicker than the galvanized layer of the steel sheet.
  • the process and the structure of the finished galvanized layer differ greatly between continuous plating of steel sheets and batch plating of steel materials. That is, the batch-type plating of steel materials is a process that is inherently prone to plating defects, and the problem is also different from the continuous plating of steel plates. For example, with regard to the above-mentioned non-plating, even when a hot dip galvanizing bath with a very low Pb concentration is used, there is no problem with the continuous plating of steel sheets, whereas with the batch-type plating of steel, non-plating occurs. It tends to be easier.
  • Patent Document 1 As a technique for improving wetability with respect to molten zinc, for example, Patent Document 1 can be cited.
  • Patent Document 1 Ni: 0.01 to 0.05% by weight, Al: 0.001 to 0.01% by weight, Bi: 0.01 to 0.08% by weight, and In: : Increasing the fluidity of the zinc bath by containing one or more of 0.05 to 0.1% by weight.
  • Patent Documents 2 to 6 even if the molten zinc bath has a Pb content suppressed to 0.1% by mass or less, non-plating occurs when a small amount of Sn, Bi, Sb, etc. is contained in the molten zinc bath. It has been shown that a hot dip galvanized material with a low content can be produced.
  • Patent Document 1 when the present inventors verified Patent Document 1, unless the Bi content was 0.3% by weight or more, the same wettability as when Pb was contained could not be obtained. Also, in Patent Documents 2 to 6, the amount of the trace element is at least 0.1% by mass, and in order to obtain even more effects, the trace element alone is contained more than 0.1% by mass or a composite Containment is necessary. Therefore, there is a problem that the product cost is increased by containing such an element.
  • an object of the present invention is to provide a method for producing a hot dip galvanized steel material and a hot dip galvanized steel material in which a high-quality plated layer is formed without causing non-plating.
  • the present inventors paid attention to a flux treatment step, a drying treatment step, and a hot dip galvanizing bath immersion treatment step in the hot dip galvanizing treatment.
  • the flux process is a process for protecting the steel surface cleaned by pickling from reoxidation and removing remaining oxides and dirt during plating.
  • the flux drying step dries the flux liquid adhered to the steel material surface and fixes the flux on the steel material surface
  • the plating step is a step of immersing the steel material in a molten zinc bath to plate the steel material surface.
  • the hot dip galvanizing process in the present invention is a so-called “deep soaking plating” performed on a steel material such as a steel pipe or a steel structure, and a hot dip galvanizing process performed on a thin steel sheet. Is different.
  • the flux conventionally used is a double salt or a mixture of zinc chloride and ammonium chloride.
  • a distilled zinc (zinc) plating bath containing Pb the wettability with respect to molten zinc is sufficiently improved when a conventional flux composed of two types of chloride is used.
  • an electrolytic zinc plating bath containing no Pb the wettability is extremely deteriorated. Therefore, in the present invention, in order to improve the wettability, the actual hot dip galvanizing situation of steel materials was investigated and studied in detail.
  • Distilled zinc as used herein is one kind of distilled zinc ingot (JIS class 1 distilled zinc ot inot) specified in JIS H2107 (1999), and Pb is usually 0.3 to 1.3 mass% and Cd is 0.
  • the electrolytic zinc is the purest zinc ingot specified in JIS H2107 (1999), and usually Pb is 0.003. Mass% or less and Cd of 0.002 mass% or less.
  • each plating bath was managed so that the purity of zinc during the plating operation was maintained at 97.5% by mass or more as shown in JIS H8641 (2007).
  • the present inventors have found that the quality of wettability in a region with a small amount of flux adhesion is important for the occurrence of non-plating, and in the region with a small amount of flux adhesion. It has been found that the wettability of the steel material to be plated with respect to hot dip zinc can be improved by containing Mg, Ti and V in the hot dip galvanizing bath. In addition, we discovered that the flux that contributes to wettability deteriorates during the period from when the steel material is immersed in the hot-dip galvanizing bath through the flux treatment to the drying treatment, and minimizes the deterioration. Manufacturing conditions were found.
  • the present invention has been completed based on the above findings and further studies.
  • the summary is as follows.
  • the component composition is Zn: 97.5 mass% or more, Fe: 1.5 mass% or less, Pb: 0.10 mass% or less, Cd: 0.00.
  • the component composition of the plating bath further includes one or two selected from Ti: 0.001 mass% to 0.05 mass%, and V: 0.001 mass% to 0.05 mass%.
  • the component composition of the plating bath further includes Al: 0.001 mass% to 0.02 mass%, and ([Mg] + [Ti] + [V]) / 2 ⁇ [Al] ( However, [Mg], [Ti], [V], and [Al] are the contents of each element.)
  • the molar ratio of zinc chloride to ammonium chloride contained in the flux solution is 1: 1 to 1: 4, and the total molar concentration of the zinc chloride and ammonium chloride contained in the flux solution is Production of hot dip galvanized steel material according to any one of [1] to [3], wherein 3 to 10 mol / L, the concentration of zinc chloride is 600 g / L or less, and the temperature of the flux solution is 40 ° C. to 85 ° C. Method.
  • T Environmental temperature (K) in an atmosphere where the steel material to be plated after flux treatment stays from the flux tank until it enters the drying furnace
  • RH Environmental relative humidity (%) in an atmosphere where the steel to be plated after flux treatment stays from the flux tank until it enters the drying furnace
  • t Residence time (minutes) from when the steel material to be plated after flux treatment exits the flux tank to the drying furnace.
  • the temperature in the drying furnace atmosphere is 180 ° C. or less
  • the dew point temperature in the drying furnace atmosphere is (steel material temperature entering the drying furnace ⁇ 10) ° C.
  • the present invention it is possible to provide a method for producing a hot dip galvanized steel material and a hot dip galvanized steel material that do not cause non-plating even when the concentration of Pb contained in the hot dip galvanizing bath is extremely low.
  • FIG. 1 is a graph showing the relationship between the molar fraction of ammonium chloride and the contact angle.
  • the “dipping soaking plating” treatment with molten zinc performed on steel is performed in the order of pickling treatment, flux treatment, drying treatment, and immersion in a hot dip galvanizing bath.
  • a degreasing treatment may be performed before the pickling treatment.
  • a water washing process may be performed as needed after a degreasing process and a pickling process.
  • the flux treatment means that the steel material surface after pickling is covered with a flux to suppress oxidation, and the flux decomposes when immersed in a hot dip galvanizing bath, thereby cleaning the steel material surface and forming a galvanized layer. It is intended to promote.
  • a flux liquid that is an aqueous solution in which the flux is dissolved in water is made, and the steel material is immersed in the flux liquid, or the flux liquid is directly applied to the surface of the steel material.
  • the manufacturing method of the hot dip galvanized steel material according to the present invention also follows this processing content and order in principle. And the technical feature demonstrated below is further added to the manufacturing method of the hot dip galvanized steel material of this invention.
  • the component composition is Zn: 97.5 mass% or more, Fe: 1.5 mass% or less, Pb: 0.10 mass% or less, Cd: 0.01 mass% or less, Mg: 0.001 mass% or more, 0.05 mass
  • the steel material to be plated is immersed in a plating bath containing no more than% and a hot dip galvanizing bath immersion treatment is performed.
  • mass% may be simply referred to as%.
  • Pb 0.10 mass% or less
  • Cd 0.01 mass% or less
  • the range in which Pb and Cd are regulated by the RoHS directive The plating bath contains Pb: 0.10 mass% or less and Cd: 0.01 mass% or less.
  • Pb is usually 0.003 mass% or less and Cd is 0.002 mass% or less. Even if it is below the detection limit, there is no problem.
  • Mg 0.001 mass% or more and 0.05 mass% or less
  • the present invention is characterized in that Mg is contained in the plating bath.
  • the inventors first investigated the wettability of the steel material to which the flux adhered to the hot dip galvanizing bath. Specifically, a Wilhelmy method (plate method) experimental apparatus used for evaluating the wettability of solder was assembled, and an experiment was performed by the method described later.
  • the Wilhelmy method is a method in which the contact angle can be obtained when the density or surface tension of a liquid is known by measuring the weight (mass) when a plate-like sample is immersed in a liquid to a certain depth.
  • a thin steel plate (50 ⁇ 20 mm, with a smooth surface and a thickness of 0.5 mm, from an electric resistance welded tube original plate) In this description, it was also referred to as a sample.) was processed, degreased, pickled, and washed with water, then dipped in a flux solution composed of zinc chloride and ammonium chloride with different concentrations, and dried. Thereafter, 10 mm from the lower end of the sample was immersed in a molten zinc bath for 20 seconds in a state where the sample was suspended on an electronic balance, and the weight during that time was recorded.
  • the weight varies even during a 20-second period when the sample is immersed in a certain amount (the surface of the sample on the bath surface is oxidized and iron oxide is formed, so it becomes harder to wet), so the maximum weight that indicates maximum wetting
  • the contact angle is 90 degrees or less, it is in a wet state and good wettability.
  • electrolytic zinc A and distilled zinc shown in Table 1 were used, respectively.
  • the state in which the flux is considered to be sufficiently attached to the steel material specifically, the flux concentration used in the flux treatment, that is, the total molar concentration of zinc chloride and ammonium chloride contained in the flux solution is 3 mol.
  • the electrolytic zinc bath containing no Pb and the distilled zinc bath containing Pb showed sufficient wettability.
  • the behavior differs between the electrolytic zinc bath and the distilled zinc bath. In the electrolytic zinc bath, the wettability deteriorated rapidly.
  • Mg is an element that is more easily oxidized than Zn or Fe.
  • Mg By covering the surface of the molten zinc bath with a thin oxide film, Mg exhibits a barrier effect that suppresses the formation of oxides of Zn, and a steel plate. Suppresses oxidation of the steel sheet surface when immersed in a zinc bath, ensuring wettability.
  • Mg content is less than 0.001 mass%, no clear effect is observed, and even when the Mg content is more than 0.05 mass%, the effect is saturated. Therefore, Mg is limited to the range of 0.001 mass% or more and 0.05 mass% or less.
  • the component composition of the plating bath may further contain one or two of Ti or V.
  • Ti improves the wettability of the steel material to which the flux is not sufficiently adhered to the hot dip galvanizing bath.
  • Ti is an element that is more easily oxidized than Zn and Fe, and suppresses oxidation of the steel sheet surface when the steel sheet is immersed in a hot dip galvanizing bath, and ensures wettability.
  • it is contained alone in the hot dip galvanizing bath, an oxide layer is formed on the surface of the hot dip galvanizing bath, and the oxide layer continues to grow with time. Therefore, in this invention, it is set as the composite containing with Mg which shows a barrier effect.
  • Ti content is less than 0.001 mass%, no clear effect is observed, and even when the Ti content is more than 0.05 mass%, the effect is saturated. Therefore, Ti is preferably in the range of 0.001 mass% to 0.05 mass%.
  • V 0.001 mass% or more and 0.05 mass% or less V improves the wettability with respect to the hot dip galvanizing bath of the steel material to which the flux is not sufficiently adhered.
  • V is an element that is more easily oxidized than Zn and Fe, and suppresses oxidation of the steel sheet surface when the steel sheet is immersed in a hot dip galvanizing bath, and ensures wettability.
  • an oxide film is formed on the surface of the hot dip galvanizing bath, and the oxide film continues to grow with time. Therefore, in this invention, it is set as the composite containing with Mg which shows a barrier effect.
  • V content is less than 0.001 mass%, no clear effect is observed, and even when the V content is more than 0.05 mass%, the effect is saturated. Therefore, V is preferably in the range of 0.001 mass% to 0.05 mass%.
  • the plating bath composition may further contain Al.
  • Al 0.001 mass% or more and 0.02 mass% or less, and ([Mg] + [Ti] + [V]) / 2 ⁇ [Al] (where [Mg], [Ti], and [V] are each element)
  • Al does not have the effect of improving the wettability of the steel to be plated with the flux not sufficiently adhered to the hot dip galvanizing bath, but Al imparts gloss to the surface of the plating layer. Therefore, there is an effect of improving the appearance of the glossy plating.
  • Al is an element that is more easily oxidized than Zn and Fe, and covers the surface of the hot dip galvanizing bath with a thin oxide film, thereby showing a barrier effect that suppresses the formation of Zn oxide.
  • Al is an element having a strong binding property with Fe, and if contained in a large amount, the alloy phase growth of Fe and Zn is hindered and causes non-plating.
  • the content of Al is less than 0.001 mass%, a clear gloss imparting effect is not recognized, and the effect is saturated even when the content is more than 0.02 mass%.
  • the wettability improving effect may be hindered.
  • a plating bath containing Zn: 97.5 mass% or more, Fe: 1.5 mass% or less and unavoidable impurities as defined in JIS, in addition to the above-described elements contained.
  • Fe the amount of Fe dissolved in the hot dip galvanizing bath increases as plating of steel materials continues.
  • the amount of Fe exceeding 0.1 mass% means the floating of the Fe—Zn alloy (so-called bottom dross), and the amount of Fe is desirably controlled to 0.1 mass% or less.
  • the plating bath has the above composition, a good hot dip galvanized steel material free from non-plating can be obtained without containing other elements.
  • one or more selected from Sb, Bi, Sn, Ni, Cu, Si, and the like may be included as necessary. .
  • the hot dip galvanizing bath immersion treatment is performed using the hot dip galvanizing bath having the component composition described above.
  • the temperature of the plating bath is preferably 440 to 470 ° C. from the viewpoint of stable production and quality. If it is less than 440 degreeC, the possibility of the solidification of the plating bath by a temperature fluctuation will increase. On the other hand, when the temperature exceeds 470 ° C., the growth of the iron-zinc alloy phase is accelerated, the plating layer becomes brittle, and the control of the plating thickness becomes difficult.
  • air or steam may be sprayed on the steel material to be plated to adjust the plating adhesion amount. Thereafter, it may be cooled by hot water cooling or air cooling.
  • Pickling treatment As the pickling treatment, a known method used for pickling treatment of steel materials can be used. For example, a method of immersing in an aqueous hydrochloric acid solution containing an inhibitor until the scale of the steel surface is visually reduced can be used. As a pre-process of the pickling treatment, a degreasing step and a water washing step may be performed as necessary.
  • the molar ratio of zinc chloride and ammonium chloride contained in the flux solution is 1: 1 to 1: 4, and the total number of moles of zinc chloride and ammonium chloride contained in the flux solution is 3 mol as the molar concentration. It is preferable that the flux treatment be performed at / L to 10 mol / L, the zinc chloride concentration is 600 g / L or less, and the temperature of the flux solution is 40 ° C. to 85 ° C.
  • the hot dip galvanizing flux is a double salt or mixture of zinc chloride and ammonium chloride.
  • Zinc chloride relieves the decomposition and disappearance of ammonium chloride due to heat in actual operation and extends the effective time of the flux.
  • Ammonium chloride is the most effective substance for cleaning the steel surface. Therefore, if either one of the substances is extremely small, the cleaning action on the steel material surface may be significantly impaired.
  • the ratio of zinc chloride to ammonium chloride is in the range of 1: 1 to 1: 4, and the minimum contact angle is particularly small, about 55 ° or less (dotted line portion). This range is particularly preferable. I understand that. Therefore, the molar ratio of zinc chloride to ammonium chloride in the hot dip galvanizing flux is preferably 1: 1 to 1: 4.
  • the concentration of flux liquid affects the amount of flux attached.
  • the total molar concentration of zinc chloride and ammonium chloride contained in the flux liquid is preferably 3 to 10 mol / L. If it is 3 mol / L, even if there is a part with a low local flux adhesion amount, plating can be performed without causing unplating.
  • the concentration of the flux liquid increases, the amount of flux adhesion increases. On the other hand, even if it exceeds 10 mol / L, the adhesion amount is saturated, the viscosity becomes high, and handling becomes difficult. For this reason, the concentration of the flux liquid is preferably 3 to 10 mol / L. Since the amount of flux attached varies, it is more preferably 5 to 10 mol / L.
  • Zinc chloride is a substance that relieves the decomposition and disappearance of ammonium chloride due to heat and extends the effective time of flux in actual operation. However, since zinc chloride is not decomposed by heat, it finally becomes zinc oxide and becomes a top dross that floats on the surface of the molten zinc bath. The top dross adheres to the surface of the steel material when the steel material is immersed in a molten zinc bath and when it is pulled up, thereby degrading the plating quality. Moreover, frequent removal of top dross also increases costs. Therefore, the concentration of zinc chloride is preferably 600 g / L or less. More desirably, it is 350 g / L or less.
  • the flux that can be used in the present invention contains at least the above zinc chloride and ammonium chloride. These double salts may be used in place of simple zinc chloride and simple ammonium chloride. The total of zinc chloride and ammonium chloride is the main component.
  • additives such as chlorides, salts, water-soluble compounds and surfactants may be included as long as the effects of the present invention are not impaired.
  • a surfactant is preferable because the amount of adhesion of the flux liquid to the steel material is made uniform, and an effect of saving flux can be expected.
  • the surfactant in the present invention include an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant, and the like. It is preferable as a component of the flux that 0% by mass of these additives and 100% by mass of the above zinc chloride, ammonium chloride and the balance as inevitable impurities.
  • the flux adhesion amount in the present invention is the total value of zinc chloride and ammonium chloride contained in the flux, and does not include the mass of other additives.
  • the flux is applied to the surface of the steel material by spraying or coating in a solution state, or by immersing in a flux bath, followed by natural drying or forced drying.
  • an aqueous solution in which the above-described flux is dissolved in water can be used as a flux solution for hot dip galvanizing.
  • Water used as a solvent can be generally used in flux treatment.
  • concentration of the flux bath for hot dip galvanization of this invention can be suitably set in the range which avoids said problem.
  • Drying treatment In the present invention, it is preferable to satisfy the following formula (1) when performing the drying treatment after the flux treatment.
  • FE 9.6 ⁇ exp ( ⁇ 2500 / T) ⁇ RH ⁇ t 0.5 ⁇ 0.85 (1)
  • T Environmental temperature (K) in the atmosphere in which the steel material to be plated after flux treatment stays between leaving the flux tank and entering the drying furnace
  • RH Environmental relative humidity (%) in the atmosphere in which the steel to be plated after flux treatment stays between leaving the flux tank and entering the drying furnace
  • t Residence time (minutes) from when the steel material to be plated after flux treatment exits the flux tank until it enters the drying furnace.
  • the flux is for protecting the steel surface from oxidation.
  • the flux liquid contains ammonium chloride
  • the liquidity is weakly acidic and promotes the elution of steel, that is, iron.
  • the flux is also used for removing the iron content eluted in the flux, the deterioration of the flux due to the elution of iron proceeds depending on the environmental conditions from the flux treatment to the drying treatment. Therefore, it is preferable to dry quickly after the flux treatment.
  • the FE value defined by the above formula (1) is an index indicating the degree of deterioration of the flux. In the present invention, if the FE value is 0.85 or less, the deterioration of the flux is suppressed to a minimum and good. Can be obtained.
  • the temperature of the flux liquid is preferably 40 ° C. or higher and 85 ° C. or lower in view of the stability of temperature holding and the heating cost.
  • the drying process is a process of evaporating the water in the flux liquid after the flux process and uniformly forming a stable flux film on the steel surface. Drying may be performed, for example, in a drying furnace. If the steel material is allowed to stand for a long time without being dried, the surface of the steel material is dissolved in the flux liquid to deteriorate the flux and inhibit the flux action. There are also examples in which combustion exhaust gas and general air are introduced into the drying furnace, and it is preferable to prevent condensation by controlling the dew point in the drying furnace. Moreover, if the temperature of the flux liquid rises too much or the stagnant time is too long, the elution of the steel material proceeds, and when the temperature rises further, the flux begins to decompose.
  • the temperature in the drying furnace atmosphere is 180 ° C. or lower
  • the dew point temperature in the drying furnace atmosphere is (the steel material temperature entering the drying furnace ⁇ 10) ° C. or lower
  • the maximum temperature reached on the steel surface during drying it is preferable to perform the drying treatment at 80 ° C. or more and 140 ° C. or less and the residence time of the steel in the drying furnace is 600 seconds or less.
  • the maximum temperature reached on the steel surface during drying is 80 ° C. or more and 140 ° C. or less
  • the residence time of the steel material in the drying furnace is 600 seconds or less in order to suppress the elution amount of the steel material while sufficiently drying. It is. If it is less than 80 degreeC, sufficient drying cannot be performed and non-plating will occur easily.
  • the maximum temperature of the steel material during drying is more preferably 120 ° C. or less.
  • the hot-dip galvanized steel material of the present invention can be obtained by the above-described method for producing a hot-dip galvanized steel material.
  • the coating weight of the hot dip galvanizing on the surface of the resulting hot dip galvanized steel is preferably 300 to 700 g / m 2 .
  • Sufficient corrosion resistance is securable by making the adhesion amount of plating into 300 g / m ⁇ 2 > or more.
  • the adhesion of plating exceeding 700 g / m 2 causes a cost increase, it is set to 700 g / m 2 or less.
  • each component of the plating layer on the surface of the steel material is such that each component of the hot-dip galvanized layer is mass%, and the total of Zn and Fe is 99.9% or more, and Pb is 0.01% or less.
  • Cd is preferably 0.005% or less.
  • the steel material (to-be-plated steel material) of the present invention is not particularly limited as long as it is a steel material that is subjected to hot dip galvanizing treatment called so-called “deep soaking plating” performed on steel pipes and steel structures.
  • hot dip galvanizing treatment of the present invention is different from the above-described continuous hot dip galvanizing treatment performed on a thin steel plate (particularly a steel strip), the thin steel plate is not a target.
  • Table 2-1 and Table 2-2 are collectively referred to as Table 2.
  • the manufacture of the hot dip galvanized steel pipe was performed in the following steps. Pickled steel pipe after degreasing (125A, 5.5m length, 11 per condition) is pickled to remove the black skin on the surface (oxide layer on the surface of the steel pipe formed during hot rolling). did.
  • the pickling solution was a 12 mass% hydrochloric acid aqueous solution containing an inhibitor, the solution temperature was 30 ° C., and the immersion time was 60 minutes. After pickling, it was washed with water, flux treatment, drying treatment, and hot dip galvanizing bath immersion were performed.
  • the flux solution was an aqueous solution of a mixture of zinc chloride and ammonium chloride, and the molar ratio of zinc chloride to ammonium chloride was mainly 1: 1.
  • the steel pipe was immersed for 30 seconds in a flux solution in which the total molar concentration of zinc chloride and ammonium chloride contained in the flux solution, the zinc chloride concentration, and the flux solution temperature were changed as shown in Table 2, and then pulled up.
  • the FE value was calculated by the equation (1) of the present invention.
  • the atmospheric temperature in the drying furnace, the dew point in the drying furnace, the maximum reached temperature and the maximum surface temperature of the steel pipe surface are as shown in Table 2, and the steel pipe surface temperature entering the drying furnace is 35 ° C. did.
  • the hot dip galvanizing bath immersion treatment eight types of A to H containing trace elements in electrolytic zinc not containing Pb and Cd, and distilled zinc as a conventional example were used as the plating bath.
  • the chemical composition is shown in Table 1.
  • the plating bath temperature and immersion time were 450 ° C. and 90 seconds, or 470 ° C. and 150 seconds. After pulling up from the hot dip galvanizing bath, excess hot dip zinc was removed by wiping and cooled by water cooling.
  • the surface of the plating layer was observed in detail, and the presence or absence of non-plating, the average number of non-plating, and the surface properties of the plating layer due to adhesion of top dross were evaluated.
  • the defective rate is calculated with a hot dip galvanized steel pipe in which one or more unplating has been confirmed as defective, and the defective rate exceeds 10%. It was. With respect to the average number of occurrences per non-plating, 0 was-, 1 to 2 was ⁇ , 3 to 5 was ⁇ , 6 or more were ⁇ , and X was rejected.
  • ⁇ is good, the top dross adheres less than ⁇ 10mm, the lightness of only one spot is rough, ⁇ , the top dross adheres to ⁇ 10mm or more, one or more, or ⁇ 10mm A moderate roughness in which less than 1 was observed at two or more locations was indicated by ⁇ , and a top roughness was 10 mm or more and a severe roughness observed at 10 or more locations was indicated by ⁇ . ⁇ , ⁇ , and ⁇ were considered acceptable. In addition, when the said defective rate exceeded 10% (failed), it did not test about the surface property of a plating layer.
  • the obtained hot-dip galvanized steel pipe was measured for the amount of hot-dip galvanized adhesion on the steel material surface and each component of the hot-dip galvanized layer.
  • the adhesion amount of the hot dip galvanization was calculated from the area and weight reduction by dissolving and removing the plated layer of the cut steel pipe.
  • Each component of the hot dip galvanized layer was similarly obtained by dissolving the plated layer and using an inductively-coupled plasma emission spectrometry method.
  • the hot dip galvanized steel pipe samples (Nos. 3 to 8, 10 to 30) of the invention examples have 10% or less non-plating, and the overall judgment is the same as the conventional example (No. 9) using distilled zinc. Passed. This is because, by including Mg in the plating bath of the present invention, the plating bath of the comparative example in which the Mg and Pb concentrations are extremely low does not cause any unplating even under conditions that cause unplating, and contains Pb. It means that it could be plated like the example. On the other hand, the hot-dip galvanized steel pipe samples (Nos. 1 and 2) of the comparative examples were all unacceptable.
  • the examples of the present invention had no or no non-plating, and all passed. On the other hand, it turns out that a comparative example is disqualified and is inferior regarding non-plating.
  • the hot dip galvanized steel material can be manufactured by a manufacturing method having sufficiently good wettability with respect to the hot dip zinc. .

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Coating With Molten Metal (AREA)

Abstract

L'objectif de la présente invention est de fournir : un procédé de production d'un matériau d'acier galvanisé par immersion à chaud présentant une bonne mouillabilité par rapport au zinc en fusion et dans lequel des défauts de placage ne sont pas générés ; et un matériau d'acier galvanisé par immersion à chaud. Dans le procédé de production d'un matériau d'acier galvanisé par immersion à chaud, un traitement par flux et un traitement par séchage sont effectués sur la surface d'un matériau d'acier destiné à être plaqué et un traitement par immersion dans un bain de galvanisation par immersion à chaud est exécuté par la suite, dans lequel le matériau d'acier destiné à être plaqué est immergé dans un bain de placage ayant une composition en constituants qui comprend une proportion supérieure ou égale à 97,5 % en masse de Zn, une proportion inférieure ou égale à 1,5 % en masse de Fe, une proportion inférieure ou égale à 0,10 % en masse de Pb, une proportion inférieure ou égale à 0,01 % en masse de Cd, et de 0,001 à 0,05 % en masse de Mg.
PCT/JP2015/003869 2014-07-31 2015-07-31 Procédé de production de matériau d'acier galvanisé par immersion à chaud, et matériau d'acier galvanisé par immersion à chaud WO2016017186A1 (fr)

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KR1020177002131A KR20170024023A (ko) 2014-07-31 2015-07-31 용융 아연 도금 강재의 제조 방법 및 용융 아연 도금 강재
CN201580041381.0A CN106661708B (zh) 2014-07-31 2015-07-31 热浸镀锌钢材的制造方法和热浸镀锌钢材

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2018095892A (ja) * 2016-12-08 2018-06-21 新日鐵住金株式会社 溶融亜鉛めっき鋼管および溶融亜鉛めっき鋼管の製造方法
JP2021031772A (ja) * 2019-08-19 2021-03-01 Ｊｆｅスチール株式会社 溶融亜鉛めっき用フラックス液および溶融亜鉛めっき鋼管の製造方法

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7147772B2 (ja) * 2017-09-26 2022-10-05 日立金属株式会社 めっき形成黒心可鍛鋳鉄部材の製造方法、並びにめっき形成黒心可鍛鋳鉄部材及び管継手
JP6919723B2 (ja) * 2017-12-25 2021-08-18 日本製鉄株式会社 溶融亜鉛めっき処理方法、その溶融亜鉛めっき処理方法を用いた合金化溶融亜鉛めっき鋼板の製造方法、及び、その溶融亜鉛めっき処理方法を用いた溶融亜鉛めっき鋼板の製造方法
CN113646459B (zh) * 2019-03-20 2023-08-15 株式会社博迈立铖 经镀覆形成的黑心可锻铸铁部件的制造方法、及经镀覆形成的黑心可锻铸铁部件
JP7311767B2 (ja) * 2019-08-30 2023-07-20 日本製鉄株式会社 フラックスおよびそれを用いる溶融Ｚｎ－Ａｌ－Ｍｇ系めっき鋼成形品の製造方法
KR102715568B1 (ko) 2022-12-09 2024-10-11 한국생산기술연구원 Zn-Al-Mg계 용융도금 강재 제조방법 및 이 방법으로 제조된 Zn-Al-Mg계 용융도금 강재

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003105493A (ja) * 2001-10-01 2003-04-09 Nippon Steel Corp 耐食性と延性に優れたＳｉ含有高強度溶融亜鉛めっき鋼板及びその製造方法
JP2003171752A (ja) * 2001-07-12 2003-06-20 Nippon Steel Corp 疲労耐久性および耐食性に優れた高強度高延性溶融Ｚｎめっき鋼板及びその製造方法
JP2011190491A (ja) * 2010-03-12 2011-09-29 Tanaka Galvanizing Co Ltd 環境負荷の少ない溶融亜鉛めっき方法及びそれを用いた溶融亜鉛めっき鋼材

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3781055B1 (ja) 2005-03-31 2006-05-31 田中亜鉛鍍金株式会社 溶融亜鉛めっき方法
JP5559479B2 (ja) 2008-01-22 2014-07-23 Ｊｆｅスチール株式会社 溶融亜鉛めっき鋼管および溶融亜鉛めっき鋼管の製造方法
JP2009221604A (ja) 2008-02-19 2009-10-01 Jfe Steel Corp 溶融亜鉛めっき鋼管および溶融亜鉛めっき材の製造方法
JP5617170B2 (ja) 2008-02-19 2014-11-05 Ｊｆｅスチール株式会社 溶融亜鉛めっき鋼管および溶融亜鉛めっき鋼管の製造方法
JP5663840B2 (ja) 2008-02-19 2015-02-04 Ｊｆｅスチール株式会社 溶融亜鉛めっき鋼管および溶融亜鉛めっき鋼管の製造方法
EP2213758A1 (fr) * 2009-01-16 2010-08-04 Galva Power Group N.V. Fondant et bain de fondant pour galvanisation à chaud, procédé de galvanisation à chaud d'un article en fer ou en acier
JP5476651B2 (ja) 2009-07-21 2014-04-23 Ｊｆｅスチール株式会社 溶融亜鉛めっき鋼管および溶融亜鉛めっき材の製造方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003171752A (ja) * 2001-07-12 2003-06-20 Nippon Steel Corp 疲労耐久性および耐食性に優れた高強度高延性溶融Ｚｎめっき鋼板及びその製造方法
JP2003105493A (ja) * 2001-10-01 2003-04-09 Nippon Steel Corp 耐食性と延性に優れたＳｉ含有高強度溶融亜鉛めっき鋼板及びその製造方法
JP2011190491A (ja) * 2010-03-12 2011-09-29 Tanaka Galvanizing Co Ltd 環境負荷の少ない溶融亜鉛めっき方法及びそれを用いた溶融亜鉛めっき鋼材

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2018095892A (ja) * 2016-12-08 2018-06-21 新日鐵住金株式会社 溶融亜鉛めっき鋼管および溶融亜鉛めっき鋼管の製造方法
JP2021031772A (ja) * 2019-08-19 2021-03-01 Ｊｆｅスチール株式会社 溶融亜鉛めっき用フラックス液および溶融亜鉛めっき鋼管の製造方法
JP7252922B2 (ja) 2019-08-19 2023-04-05 Ｊｆｅスチール株式会社 溶融亜鉛めっき用フラックス液および溶融亜鉛めっき鋼管の製造方法

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JP6137339B2 (ja) 2017-05-31

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