EP1307609B1 - Methode zum kontinuierlichen elektrolytischen beizen von metallen mittels wechselstrom gespeisten zellen - Google Patents

Methode zum kontinuierlichen elektrolytischen beizen von metallen mittels wechselstrom gespeisten zellen Download PDF

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Publication number
EP1307609B1
EP1307609B1 EP01961136A EP01961136A EP1307609B1 EP 1307609 B1 EP1307609 B1 EP 1307609B1 EP 01961136 A EP01961136 A EP 01961136A EP 01961136 A EP01961136 A EP 01961136A EP 1307609 B1 EP1307609 B1 EP 1307609B1
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Prior art keywords
electrolytic
pickling method
concentration
acid
electrolytic pickling
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French (fr)
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EP1307609A2 (de
Inventor
L. Centro Sviluppo Materiali S.p.A. PACELLI
V. Centro Sviluppo Materiali S.p.A. FERRARI
Stefano Centro Sviluppo Materiali S.p.A. LUPERI
Mauro Centro Sviluppo Materiali S.p.A. CAMPIONI
Bruno Centro Sviluppo Materiali S.p.A. FERRI
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Centro Sviluppo Materiali SpA
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Centro Sviluppo Materiali SpA
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    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25F—PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR
    • C25F1/00—Electrolytic cleaning, degreasing, pickling or descaling
    • C25F1/02—Pickling; Descaling
    • C25F1/04—Pickling; Descaling in solution
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25F—PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR
    • C25F1/00—Electrolytic cleaning, degreasing, pickling or descaling
    • C25F1/02—Pickling; Descaling
    • C25F1/04—Pickling; Descaling in solution
    • C25F1/06—Iron or steel

Definitions

  • the present invention relates to a continuous electrolytic pickling method for metallic products, in particular in Iron, Nickel, Titanium and alloys thereof, based on the use of alternate current supplied cells with electrolytic solution consisting of acid or neutral aqueous solutions.
  • pickling e.g. for the stainless steels
  • pickling is actually carried out in order to eliminate the scale of thermal oxides which are generated during the hot-rolling and/or annealing treatments, and to dissolve the Chromium-depleted alloy layer (dechromized layer) therebelow.
  • This conventional method consists of three conceptually different steps: a first step of descaling, i.e., physico-chemical modification of the scale with the partial removal thereof; a second step of actual pickling, i.e. removal and solution of the residual scale and disposal of the sub-surface layer of dechromized alloy; and a third step, so-called of finishing, consisting in a surface passivation.
  • the latter two steps are often carried out at the same time.
  • the step of descaling is carried out by sandblasting with a hard grit which breaks up and partially removes the scale.
  • the step of descaling cannot be carried out by surface peening, which is not compatible with the quality of the finished product's surface.
  • the pickling step is generally carried out using highly oxidizing acid baths, capable of dissolving the sub-surface alloy layer (Cr-depleted for stainless steels) determining the detachment of the scale adhering thereto.
  • electrolytic cells capable of applying a continuous current density ranging from 3 A/dm 2 to 40 A/dm 2 to the material are used.
  • the finishing step aimed at forming a passivated protective film, when this is not carried out at the same time as the pickling step, is usually attained in baths having high redox potential.
  • These baths contain the abovementioned acids and oxidizers at lower concentrations and with a lower content of the ions of the metals present in the metallic products to be pickled.
  • washing sections consisting of water jet systems equipped with rotary brushes are inserted.
  • the function carried out by these systems is the removal of the pickling solution dragged by the strip, and the non-adhering scale particles deposed on the strip surface.
  • DE-A-19624436, WO 9826111, EP-A-763609 and JP95-130582 disclose pickling processes in acid solution, free from nitric acid, in presence of ferric ions with the use of alternate current supplied electrolytic cells (current density comprised between 0.5 A/dm2 and 250 A/dm2).
  • DE-C-3937438 discloses a process in which direct current is employed for the reoxidation of the ferrous ions to ferric ions in a hydrochloric acid solution.
  • EP-A-838542 discloses a pickling process in an aqueous sodium sulphate solution, having a concentration between 10 g/l and 350 g/l, in which the strip is vertically passed between pairs of counter electrodes, a direct current having a density between 20 A/dm2 and 250 A/dm2 being applied therebetween.
  • the main drawback of the process for the mechanical removal of the scale by sandblasting or peening lies in the difficulty of abating the dusts made of silica and metallic oxides particles, not to mention the high noise pollution of the surrounding working areas.
  • the baths of sulphuric and of hydrofluoric acid which use, instead of the nitric acid, systems having a high redox potential, entail a complex management in connection with the difficulties of maintaining the appropriate concentrations of reagents capable of ensuring the envisaged pickling kinetics.
  • the costs of the reagents e.g., of the stabilised hydrogen peroxide, are high, considering that a fraction of the metals accumulating in the solution react with the oxidizers, lowering the process effectiveness.
  • the present invention allows to overcome all of the abovementioned drawbacks, further providing other advantages which will hereinafter be made apparent.
  • an object of the present invention is to provide a pickling method for continuously cast products in steel, in compliance of the UNI EU 74/20 norm, and in Nickel alloy and in Titanium, based on the use of alternate current supplied electrolytic cells in acid or neutral aqueous solutions.
  • an object of the present invention is a continuous electrolytic pickling method for steels, Nickel super alloys, Titanium and alloys thereof, characterised in that the material to be treated, for a time between 3 and 60 seconds, is immersed into or passes through at least one electrolytic cell with an electrolytic solution, free of nitric acid, consisting of a neutral or acid aqueous solution, at a temperature between 20°C and 95°C, with at least one pair of electrodes connected to an alternate current power supply having a frequency ranging from 40 Hz to 70 Hz, the electrolysis being carried out at a current density having an effective amplitude ranging from 10 A/dm2 to 250 A/dm2.
  • the electrolytic solution can be an aqueous solution, at a temperature between 20°C and 95°C, containing the following components having a concentration expressed in g/l:
  • the electrolytic solution is maintained at a temperature between 70°C and 90°C and comprises sulphuric acid at a concentration between 150 g/l and 250 g/l, and ferric ions (Fe +3 ) at a concentration of from 5 g/l to 40 g/l.
  • the electrolytic solution is at a temperature between 70°C and 90°C, and comprises sulphuric acid at a concentration between 150 g/l and 250 g/l and at least one between hydrofluoric acid at a concentration between 5 g/l and 50 g/l and hydrochloric acid at a concentration between 5 g/l and 50 g/l.
  • the electrolytic solution is at 70°C-90°C and comprises sulphuric acid at a concentration between 150 g/l and 250 g/l.
  • the electrolytic solution may be a sodium sulphate (Na 2 SO 4 ) neutral aqueous solution having a concentration ranging from 25 g/l to 300 g/l at a temperature between 50°C and 95°C.
  • Na 2 SO 4 sodium sulphate
  • pairs of adjacent electrodes are connected to two separate power supplies, so that the current lines outputted from a first electrode pair facing one side of the material to be treated, cross said material and close again on a second electrode pair, opposed to the first one and facing the other side of the material to be treated, defining a substantially X-shaped course.
  • electrodes facing one side of the material to be treated are connected to a power supply, so that the current lines which are outputted from said electrodes and cross the material, close again on other electrodes opposed to the first ones and facing the opposite side of the material to be treated, defining a course which is substantially orthogonal to said sides.
  • the electrolytic pickling method according to the invention can be used for inducing a physical-chemical modification of the scale of the metallic oxides present onto the surface of the material to be pickled, a physical-chemical modification which, in the case of the stainless steels, occurs in a treatment time comprised between 1 sec and 10 sec.
  • the continuous electrolytic pickling method according to the present invention may be used in a step subsequent to that of the physical-chemical modification of the scale of metallic oxides present onto the surface of the material to be pickled.
  • this application of the pickling method according to the invention requires treatment times between 2 sec and 15 sec.
  • the electrolytic cells employable in the present invention may be vertical electrode or horizontal electrode cells, the former ones being preferable for the easy scavenging of the gas evolved by electrochemical reaction at made circuit.
  • the electrodes are made in materials resistant to the corrosive action of the baths employed.
  • the electrodes in the individual cell are connectable according to at least three schemes, reported by way of a non-limiting example in the attached Figs. 2, 3 and 4.
  • the electrodes may consist of an individual toroidal ring.
  • Another object of the present invention are the electrolytic cells characterised in that they have an electrode connection as indicated hereinafter and claimed in claims 8 and 9.
  • the AC flow induces an over voltage of the free corrosion potential on the surface of the alloy to be pickled, so as to reach thereon electrochemical potentials capable of fostering several oxidation-reduction reactions which involve both the alloy and the oxide layer thereabove, as well as the aqueous solution.
  • the dissolved Iron, in form of ferrous ion deriving from the solution of steel, is capable of fostering the reduction, according to the abovedescribed reaction, of all the Cr (VI) ions to Cr (III) ions, so that the Cr (VI) ions be absent from the solution.
  • the voltage-current phase displacement assessed by electrode impedance spectroscopy, is such that at frequencies between 40 Hz and 70 Hz more than 90% of the current crossing the cell is in phase with the applied voltage (active component of the current) and it allows the abovementioned electrochemical reactions.
  • a mere 10% of the current is shifted 90° out of phase with respect to the voltage (reactive component of the current) it being employed, for the load, the discharge of the pseudo-condenser made by the double electric charge layer on the electrode surface.
  • the active component tends to decrease in favour of the reactive one, decreasing the fraction of the current fostering the electrochemical reactions required for the pickling.
  • the solution kinetics of the alloys to be pickled are high, particularly so, considering that the oxide is in no way pre-treated or conditioned prior to the in-cell electrolytic treatment.
  • Figure 1 shows the progress of the weight loss expressed in g/m 2 as a function of the time for the entire pickling treatment in a 200 g/l H 2 SO 4 aqueous solution for a X 6 CrTi 12 (AISI 409) cold-rolled and annealed steel.
  • Figure 2 shows a first electrode configuration, in which electrodes 1 located at the same side of the strip N are alternately connected to the two terminals of a phase of a transformer.
  • the electrodes 2 located at the side opposed to the strip are connectable to the same terminal of a phase of a transformer, connecting them to the corresponding ones on the other side.
  • Figure 3 shows a second configuration in which the electrodes 1 located in the same side of strip N are connected to the same terminal of one or more phases of one or more transformers, and the opposed electrodes 2 are connected to the other terminal of the corresponding phases of the transformers.
  • the current is applied with the electrode configuration shown in figure 2.
  • the interelectrode gap is equal to 80 mm.
  • the in-tank solution is such as to maintain with the immersed strip surface a ratio not lower than 1m 3 solution/m 3 strip and it is renewed upon reaching the limits set for the dissolved metals.
  • the treatment time i.e., the period in which the material is subjected to the action of the alternate current, was set at 15 sec, in connection with the strip speed and the electrode sizes.
  • the weight loss attained at the end of the treatment was equal to about 40 g/m 2 of strip.
  • Figure 1 shows the diagram related to the weight losses of the steel subject of the example as a function of the treatment time and for two different current densities applied.
  • the current was applied with the electrode configuration shown in figure 2.
  • the interelectrode gap is equal to 80 mm.
  • the in-tank solution is such as to maintain with the immersed strip surface a ratio not lower than 1m 3 solution/m 2 strip and it is renewed upon reaching the limits set for the dissolved metals.
  • the treatment time i.e., the period in which the material is subjected to the action of the alternate current, was set at between 5 sec and 25 sec, in connection with the strip speed and the electrode sizes
  • the weight loss attained at the end of the treatment was equal to about 40 g/m 2 of strip.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
  • Electrolytic Production Of Metals (AREA)

Claims (14)

  1. Verfahren zum kontinuierlichen elektrolytischen Beizen von Stählen, Nickelbasi-Superlegierungen, Titan und dessen Legierungen, dadurch gekennzeichnet, dass das zu behandelnde Material für einen Zeitraum zwischen 3 Sek. und 60 Sek. in wenigstens eine elektrolytische Zelle eingetaucht wird oder durch diese hindurch bewegt wird, welche eine elektrolytische Lösung aufweist, die keine Salpetersäure enthält, bestehend aus einer neutralen oder sauren wässrigen Lösung, umfassend Schwefelsäure mit zwischen 20 bis 300 g/l, bei einer Temperatur zwischen 20°C und 95°C, wobei wenigstens ein Elektrodenpaar mit einer Wechselstromversorgung mit einer Frequenz in dem Bereich von 40 Hz bis 70 Hz verbunden ist, und wobei die Elektrolyse bei einer Stromdichte mit einer wirksamen Amplitude in dem Bereich von 10 Å/dm2 bis 250 Å/dm2 durchgeführt wird.
  2. Verfahren zum elektrolytischen Beizen nach Anspruch 1, wobei die elektrolytische Lösung eine wässrige Lösung ist, bei einer Temperatur zwischen 20°C und 95°C, enthaltend die folgenden Bestandteile mit den in g/l ausgedrückten Konzentrationen:
    Schwefelsäure (H2SO4) zwischen 20 bis 300, und wenigstens eines von
    Flusssäure (HF) zwischen 5 bis 50
    Orthophosphorsäure (H3PO4) zwischen 5 bis 200
    Eisen(III)-lon (Fe+3) zwischen 5 bis 40.
  3. Verfahren zum elektrolytischen Beizen von rostfreien Stählen, gemäß einem der Ansprüche 1 oder 2, wobei die elektrolytische Lösung auf einer Temperatur zwischen 70°C und 90°C gehalten wird und Schwefelsäure mit einer Konzentration zwischen 150 g/l und 250 g/l und Eisen(III)-lonen (Fe+3) mit einer Konzentration von zwischen 5 g/l und 40 g/l enthält.
  4. Verfahren zum elektrolytischen Beizen von Nickelbasis-Superlegierungen und von Titan und dessen Legierungen gemäß Anspruch 1 bis 2, wobei die elektrolytische Lösung auf einer Temperatur zwischen 70 und 90°C gehalten wird, und Schwefelsäure mit einer Konzentration zwischen 150 g/l und 250 g/l und wenigstens eines gewählt aus Flusssäure mit einer Konzentration zwischen 5 g/l und 50 g/l und Salzsäure mit einer Konzentration zwischen 5 g/l und 50 g/l enthält.
  5. Verfahren zum elektrolytischen Beizen von Kohlenstoffstahl gemäß einem der Ansprüche 1 bis 2, wobei die elektrolytische Lösung auf 70°C - 90°C gehalten wird und Schwefelsäure mit einer Konzentration zwischen 150 g/l und 250 g/l umfasst.
  6. Verfahren zum elektrolytischen Beizen nach Anspruch 1, wobei die elektrolytische Lösung eine wässrige Natriumsulfat (Na2SO4) Lösung ist, mit einer Konzentration im Bereich von 25 g/l bis 300 g/l bei einer Temperatur zwischen 50°C und 95°C.
  7. Verfahren zum elektrolytischen Beizen nach einem der Ansprüche 1 - 6, wobei Paare einander benachbarter Elektroden mit zwei getrennten Stromversorgungen verbunden sind, so dass die Stromlinien, welche von einem ersten Elektrodenpaar, das einer Seite des zu behandelnden Materials gegenüberliegt, ausgestoßen werden, das Material kreuzen und sich wieder an einem zweiten Elektrodenpaar schließen, welches dem ersten Paar gegenüberliegt und das der anderen Seite des zu behandelnden Materials gegenüberliegt, wodurch ein im wesentlichen X-förmiger Verlauf definiert wird.
  8. Verfahren zum elektrolytischen Beizen nach einem der Ansprüche 1 - 6, wobei die Elektroden, welche einer Seite des zu behandelnden Materials gegenüberliegen, mit einer Stromversorgung verbunden sind, so dass die Stromlinien, welche von diesen Elektroden ausgestoßen werden und das Material kreuzen, sich wieder an den anderen Elektroden schließen, welche den ersten Elektroden gegenüberliegen und den gegenüberliegenden Seiten des zu behandelnden Materials gegenüberliegen, wodurch ein Verlauf definiert wird, welcher zu den Seiten des zu behandelnden Materials im wesentlichen orthogonal ist.
  9. Verwendung eines Verfahrens zum elektrolytischen Beizen nach einem der Ansprüche 1 - 8, zum induzieren einer physikalisch-chemischen Modifikation des Anteils bzw. Ausmaßes der metallischen Oxide, die auf der Oberfläche des zu beizenden Materials vorhanden sind.
  10. Verwendung eines Verfahrens zum elektrolytischen Beizen nach Anspruch 9, an rostfreien Stählen, mit einer Behandlungsdauer zwischen 1 und 10 Sekunden.
  11. Verwendung des Verfahrens zum elektrolytischen Beizen nach einem der Ansprüche 1 - 8, in einem Schritt, welcher auf die physikalisch-chemische Modifikation des Anteils bzw. Ausmaßes der metallischen Oxide, welche auf der Oberfläche des zu beizenden Materials vorhanden sind, folgt.
  12. Verwendung eines Verfahrens zum elektrolytischen Beizen nach Anspruch 11 - in einem Schritt, welcher auf den der physikalisch-chemischen Modifikation des Anteils bzw. Ausmaßes der metallischen Oxide, die auf der Oberfläche des zu beizenden Materials vorhanden sind, folgt - an rostfreien Stählen, mit einer Behandlungsdauer zwischen 2 Sek. und 15 Sek.
  13. Verwendung des Beizverfahrens nach Anspruch 1 - 12, kombiniert mit anderen herkömmlichen Beizsystemen.
  14. Elektrolytische Zelle, dadurch gekennzeichnet, dass sie eine Elektrodenverbindung aufweisen, wie in Anspruch 7 oder 8 angegeben.
EP01961136A 2000-08-10 2001-08-06 Methode zum kontinuierlichen elektrolytischen beizen von metallen mittels wechselstrom gespeisten zellen Expired - Lifetime EP1307609B1 (de)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
ITRM20000456 2000-08-10
IT2000RM000456A IT1317896B1 (it) 2000-08-10 2000-08-10 Metodo di decapaggio elettrolitico continuo di prodotti metallici concelle alimentate a corrente alternata.
PCT/IT2001/000435 WO2002012596A2 (en) 2000-08-10 2001-08-06 Continuous electrolytic pickling method for metallic products using alternate current supplied cells

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EP1307609A2 EP1307609A2 (de) 2003-05-07
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US (1) US20040031696A1 (de)
EP (1) EP1307609B1 (de)
CN (1) CN1318652C (de)
AT (1) ATE262057T1 (de)
AU (1) AU2001282513A1 (de)
DE (1) DE60102387T2 (de)
ES (1) ES2220795T3 (de)
IT (1) IT1317896B1 (de)
WO (1) WO2002012596A2 (de)

Families Citing this family (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10160318A1 (de) * 2001-12-07 2003-06-18 Henkel Kgaa Verfahren zum Beizen von martensitischem oder ferritischem Edelstahl
DE102008057151A1 (de) * 2008-11-13 2010-05-27 Henkel Ag & Co. Kgaa Verfahren zum Herstellen eines elektrolytisch verzinkten hochfesten Stahlbleches
CN102260899B (zh) * 2010-05-25 2013-04-03 宝山钢铁股份有限公司 钛/钛合金板带表面氧化皮去除方法
US20120168320A1 (en) * 2010-12-30 2012-07-05 Monique Chauntia Bland System and method for scale removal from a nickel-based superalloy component
JP6144006B2 (ja) * 2011-01-17 2017-06-07 Ｊｆｅスチール株式会社 燃料電池セパレータ用ステンレス鋼の製造方法、燃料電池セパレータ用ステンレス鋼、燃料電池セパレータ、ならびに燃料電池
CN103014824A (zh) * 2011-09-21 2013-04-03 李文志 低碳型交流电化学除油工艺方法
ITMI20130493A1 (it) 2013-03-29 2014-09-30 Tenova Spa Metodo per trattare in continuo la superficie di un laminato di acciaio inossidabile in una soluzione a base di acido solforico
ITMI20130494A1 (it) 2013-03-29 2014-09-30 Tenova Spa Metodo per trattare in continuo la superficie di un laminato di acciaio inossidabile in una soluzione a base di acido cloridrico
DE102015202963A1 (de) * 2015-02-18 2016-08-18 Ulrich Schekulin Verfahren und Vorrichtung zur chemisch materialabtragenden Öffnungsrandstrukturierung
CN107525062A (zh) * 2017-08-23 2017-12-29 大唐东北电力试验研究所有限公司 一种火电厂过热器管样垢量测定系统及方法
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JP7177425B2 (ja) * 2017-12-28 2022-11-24 株式会社日本科学エンジニアリング ステンレス鋼用電解研磨液
CN110592600A (zh) * 2019-09-23 2019-12-20 中冶南方工程技术有限公司 一种冷轧430铁素体不锈钢无硝酸酸洗工艺
CN110512217A (zh) * 2019-09-23 2019-11-29 中冶南方工程技术有限公司 一种冷轧201奥氏体不锈钢无硝酸酸洗工艺
CN110528009A (zh) * 2019-09-23 2019-12-03 中冶南方工程技术有限公司 一种冷轧304奥氏体不锈钢无硝酸酸洗工艺
KR102286367B1 (ko) * 2019-11-11 2021-08-05 주식회사 포스코 고분자 연료전지 분리판용 스테인리스강의 제조방법
CN111621840A (zh) * 2020-05-26 2020-09-04 大连理工大学 一种钛合金表面铁污染的双极电化学清除方法
KR102497442B1 (ko) * 2020-11-25 2023-02-08 주식회사 포스코 접촉저항이 향상된 고분자 연료전지 분리판용 오스테나이트계 스테인리스강 및 그 제조 방법
CN113788520A (zh) * 2021-10-08 2021-12-14 北京首钢吉泰安新材料有限公司 一种铁铬铝酸洗的工艺及废水处理方法和废水处理装置

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USRE19773E (en) * 1935-12-03 Euectrocleanuxg process
US2115005A (en) * 1936-10-15 1938-04-26 Samuel J Blaut Electrochemical treatment of metal
US2408424A (en) * 1940-06-15 1946-10-01 Monsanto Chemicals Pickling steels
US4214961A (en) * 1979-03-01 1980-07-29 Swiss Aluminium Ltd. Method and apparatus for continuous electrochemical treatment of a metal web
GB8517606D0 (en) * 1985-07-12 1985-08-21 Bekaert Sa Nv Cleaning by electrochemical pickling
US4813395A (en) * 1987-04-27 1989-03-21 Allied Corporation Two-cycle engine and method of operation
SU1723209A1 (ru) * 1988-11-30 1992-03-30 Уральский научно-исследовательский институт трубной промышленности Способ электрохимического травлени стальных изделий
JPH0726240B2 (ja) * 1989-10-27 1995-03-22 ペルメレック電極株式会社 鋼板の電解酸洗又は電解脱脂方法
AT399167B (de) * 1991-06-10 1995-03-27 Andritz Patentverwaltung Verfahren und vorrichtung zum elektrolytischen beizen von kontinuierlich durchlaufendem elektrisch leitendem gut
SE501561C2 (sv) * 1993-05-09 1995-03-13 Swedish Pickling Ab Förfarande och anordning vid betning av rostfritt stål varvid strömmen leds igenom stålbandet i dess tjockleksriktning
AT401183B (de) * 1995-02-15 1996-07-25 Andritz Patentverwaltung Verfahren zur regeneration von elektrolyten, insbesondere na2so4 aus abbeizen von edelstahl, insbesondere edelstahlbändern
IT1276955B1 (it) * 1995-10-18 1997-11-03 Novamax Itb S R L Processo di decapaggio e passivazione di acciaio inossidabile senza impiego di acido nitrico
IT1302202B1 (it) * 1998-09-11 2000-07-31 Henkel Kgaa Processo di decapaggio elettrolitico con soluzioni esenti da acidonitrico.
GB2358194B (en) * 2000-01-17 2004-07-21 Ea Tech Ltd Electrolytic treatment

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WO2002012596A3 (en) 2002-04-25
US20040031696A1 (en) 2004-02-19
EP1307609A2 (de) 2003-05-07
DE60102387T2 (de) 2005-03-24
WO2002012596A9 (en) 2002-11-28
CN1318652C (zh) 2007-05-30
ES2220795T3 (es) 2004-12-16
AU2001282513A1 (en) 2002-02-18
ITRM20000456A1 (it) 2002-02-10
CN1451058A (zh) 2003-10-22
ATE262057T1 (de) 2004-04-15
WO2002012596A2 (en) 2002-02-14
DE60102387D1 (de) 2004-04-22
ITRM20000456A0 (it) 2000-08-10
IT1317896B1 (it) 2003-07-15

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