IE47623B1 - Process for surface-finishing shaped elements consisting of zinc or zinc alloys - Google Patents
Process for surface-finishing shaped elements consisting of zinc or zinc alloysInfo
- Publication number
- IE47623B1 IE47623B1 IE2551/78A IE255178A IE47623B1 IE 47623 B1 IE47623 B1 IE 47623B1 IE 2551/78 A IE2551/78 A IE 2551/78A IE 255178 A IE255178 A IE 255178A IE 47623 B1 IE47623 B1 IE 47623B1
- Authority
- IE
- Ireland
- Prior art keywords
- zinc
- shaped element
- volume
- shaped elements
- elements consisting
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims abstract description 19
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 title claims abstract description 15
- 239000011701 zinc Substances 0.000 title claims abstract description 15
- 229910052725 zinc Inorganic materials 0.000 title claims abstract description 15
- 229910001297 Zn alloy Inorganic materials 0.000 title claims abstract description 9
- 238000005554 pickling Methods 0.000 claims abstract description 11
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims abstract description 5
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims abstract description 5
- 229910017604 nitric acid Inorganic materials 0.000 claims abstract description 5
- 239000001117 sulphuric acid Substances 0.000 claims abstract description 5
- 235000011149 sulphuric acid Nutrition 0.000 claims abstract description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 4
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 2
- 229910052804 chromium Inorganic materials 0.000 claims description 2
- 239000011651 chromium Substances 0.000 claims description 2
- 150000003018 phosphorus compounds Chemical class 0.000 claims description 2
- 238000005096 rolling process Methods 0.000 abstract description 3
- 238000000576 coating method Methods 0.000 description 6
- 229910052751 metal Inorganic materials 0.000 description 5
- 238000005530 etching Methods 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000004532 chromating Methods 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- ONDPHDOFVYQSGI-UHFFFAOYSA-N zinc nitrate Chemical compound [Zn+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O ONDPHDOFVYQSGI-UHFFFAOYSA-N 0.000 description 2
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- 229910001069 Ti alloy Inorganic materials 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- PTFCDOFLOPIGGS-UHFFFAOYSA-N Zinc dication Chemical compound [Zn+2] PTFCDOFLOPIGGS-UHFFFAOYSA-N 0.000 description 1
- XUDNJARNPKNDSJ-UHFFFAOYSA-N [Ti].[Cu].[Zn] Chemical compound [Ti].[Cu].[Zn] XUDNJARNPKNDSJ-UHFFFAOYSA-N 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000004411 aluminium Substances 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 230000001680 brushing effect Effects 0.000 description 1
- ZCDOYSPFYFSLEW-UHFFFAOYSA-N chromate(2-) Chemical compound [O-][Cr]([O-])(=O)=O ZCDOYSPFYFSLEW-UHFFFAOYSA-N 0.000 description 1
- KRVSOGSZCMJSLX-UHFFFAOYSA-L chromic acid Substances O[Cr](O)(=O)=O KRVSOGSZCMJSLX-UHFFFAOYSA-L 0.000 description 1
- ABXXWVKOBZHNNF-UHFFFAOYSA-N chromium(3+);dioxido(dioxo)chromium Chemical compound [Cr+3].[Cr+3].[O-][Cr]([O-])(=O)=O.[O-][Cr]([O-])(=O)=O.[O-][Cr]([O-])(=O)=O ABXXWVKOBZHNNF-UHFFFAOYSA-N 0.000 description 1
- VQWFNAGFNGABOH-UHFFFAOYSA-K chromium(iii) hydroxide Chemical compound [OH-].[OH-].[OH-].[Cr+3] VQWFNAGFNGABOH-UHFFFAOYSA-K 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000005238 degreasing Methods 0.000 description 1
- 238000009713 electroplating Methods 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- AWJWCTOOIBYHON-UHFFFAOYSA-N furo[3,4-b]pyrazine-5,7-dione Chemical compound C1=CN=C2C(=O)OC(=O)C2=N1 AWJWCTOOIBYHON-UHFFFAOYSA-N 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 150000007522 mineralic acids Chemical class 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- UOURRHZRLGCVDA-UHFFFAOYSA-D pentazinc;dicarbonate;hexahydroxide Chemical compound [OH-].[OH-].[OH-].[OH-].[OH-].[OH-].[Zn+2].[Zn+2].[Zn+2].[Zn+2].[Zn+2].[O-]C([O-])=O.[O-]C([O-])=O UOURRHZRLGCVDA-UHFFFAOYSA-D 0.000 description 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 1
- 239000010452 phosphate Substances 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000011253 protective coating Substances 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000011265 semifinished product Substances 0.000 description 1
- 235000010269 sulphur dioxide Nutrition 0.000 description 1
- 239000004291 sulphur dioxide Substances 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
- C23G1/10—Other heavy metals
-
- 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
- C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
- C23C22/06—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6
- C23C22/48—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 not containing phosphates, hexavalent chromium compounds, fluorides or complex fluorides, molybdates, tungstates, vanadates or oxalates
- C23C22/53—Treatment of zinc or alloys based thereon
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Treatment Of Metals (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
- Electroplating Methods And Accessories (AREA)
Abstract
A process is described for surface-finishing shaped elements consisting of zinc or zinc alloys, particularly of sheets and strips made by rolling, by pickling the shaped elements in a solution which contains 60 to 90% by volume of water and 10 to 40% by volume of nitric acid, and which may contain up to 10% by volume of sulphuric acid. The elements are thus preweathered and the colour may be varied by the speed at which the elements are moved through the pickling solution.
Description
This invention relates to a process for surfacefinishing by preventing shaped elements consisting of zinc or zinc alloys, particularly elements in the form of sheets and strip made by rolling.
Under normal atmospheric conditions, protective coatings of basic zinc carbonate are formed on the surfaces of shaped elements consisting of zinc or zinc alloys, the formation of these coatings taking about three days in an atmosphere having a relative humidity of 75%. Depending upon the composition of the alloy, the location, the atmosphere and the time, these coatings are light-grey to dark-grey in colour. The formation of these coatings can be retarded or prevented by pollutants, such as sulphur dioxide, contained in the air.
For this reason a surface-finishing treatment is often required for improving the appearance of the shaped elements. Such a treatment also provides technological advantages because a more uniform coating can be formed. The surface-finishing treatment may be conducted so as to obtain a uniform colour, which is often highly desirable for improved appearance.
Zinc can be chemically passivated by electroplating as well as by chromating and phosphating processes, which are used on a relatively large scale.
- 3 In a chromating process, the surfaces which have been cleaned and pretreated are treated with dilute chromic acid or chromate solutions. Inorganic acids or salts may be added to said solutions in certain proportions in order to obtain certain hues or to control the thickness of the coatings. The surfaces treated in this manner have hues from pale yellow to olive-brown and the covering layer which consists of chromium hydroxide and basic chromium (III) chromate, has a thickness from less than 1 micron to about 5 microns.
Phosphating can be effected by pickling with phosphoric acid or by film-forming phosphating processes after a suitable pretreatment, the phosphate coatings usually having a thickness of from 2 to 15 microns.
These passivating processes involve a relatively large number of steps and, for this reason, are expensive. They also have the disadvantage that the chromated or phosphated semifinished products must be pretreated before they can be soldered. For this reason the use of zinc sheets in construction work is rather difficult.
A process for etching metals has been proposed employing a liguid etching bath which contains metal which has been previously dissolved by etching in which process the amount of dissolved metal is maintained at an optimum level, It is indicated that the metal may be zinc or copper or magnesium and the etchant may comprise nitric acid with or without any of the well known additives and also comprising, when etching zinc, zinc ions as provided by e.g. zinc nitrate. There is however no suggestion that the etchant could be used in any way to surface-finish or preweather zinc or its alloys.
According to the present invention there is pro47623
- 4 vided a process for preweathering a shaped element consisting of zinc or a zinc alloy wherein the shaped element is pickled in a solution which contains nitric acid in an amount of from 10 to 40% by volume, sulphuric acid in an amount of up to 10% by volume, remainder water and which is substantially free of chromium or phosphorus compounds, for a period of time sufficient for the surface of the element to become a dark grey to black colour. This process enables the surfaces of shaped elements consisting of zinc or zinc alloys, particularly of strip and sheets made by rolling, to be preweathered. The invention also resides in the shaped elements preweathered by this process.
The pickling process can be accelerated and the colour can be influenced by an addition of up to 10% by volume of sulphuric acid to tbe pickling solution.
Depending upon the desired colour, the shaped element may be moved through the pickling solution at a speed of 0.5 to 50 metres per minute, preferably 0.5 to
metre's per minute.
Any foreign matter on the shaped elements which are to be pickled must be removed by degreasing and possibly by rinsing and brushing, prior to the pickling treatment.
In order to enable the invention to be more readily understood, an example thereof will now be described.
In this Example of the present process, a rolled strip having a thickness of 0.72 mm. and composed of a zinc-copper-titanium alloy consisting of 0.14% by weight of copper, 0.13% by weight of titanium, 0.01% by weight of aluminium, balance high-grade zinc, was pulled at a speed of 8 metres per minute through a pickling bath consisting of 85% by volume of water, 10% by volume of nitric acid and 5% by volume of sulphuric acid and was subsequently rinsed, brushed and dried. After this
- 5 pickling treatment, the surface of the strip had a dark grey to black colour.
An advantage of the present invention is that shaped elements consisting of zinc or zinc alloys can be preweathered in a relatively simple manner and it is no longer necessary to wait until a prolonged action of atmospheric influences has resulted in a light grey to dark grey colour of the surface. This advantage is particularly significant in view of the desire that sheet metal elements, e.g. those used in construction, should have a uniform colour for the sake of appearance. The preweathered surface can also act as a key for a subsequently applied paint so that no primer is required in this case, Another important advantage is that the preweathered shaped elements can be soldered with entirely conventional means.
Claims (5)
1. A process for preweathering a shaped element consisting of zinc or a zinc alloy wherein the shaped element is pickled in a solution which 5 contains nitric acid in an amount of from 10 to 40% by volume, sulphuric acid in an amount of up to 10% by volume, remainder water, and which is substantially free of chromium or phosphorus compounds, for a period of time sufficient for the surface of the element to 10 become a dark grey to black colour.
2. A process as claimed in claim 1 wherein the shaped element is moved through the pickling solution at a speed of 0.5 to 50 metres per minute.
3. A process as claimed in claim 1 or 2 15 wherein the shaped element is moved through the pickling solution at a speed of 0.5 to 30 metres per minute.
4. A process for preweathering a shaped element consisting of zinc or a zinc alloy substantially as hereinbefore described in the foregoing Example. 20
5. A shaped element preweathered by the process claimed in any preceding claim.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE2757592A DE2757592C2 (en) | 1977-12-23 | 1977-12-23 | Process for the production of cover layers on molded bodies made of zinc-copper-titanium alloys |
Publications (2)
Publication Number | Publication Date |
---|---|
IE782551L IE782551L (en) | 1979-06-23 |
IE47623B1 true IE47623B1 (en) | 1984-05-02 |
Family
ID=6027048
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
IE2551/78A IE47623B1 (en) | 1977-12-23 | 1978-12-21 | Process for surface-finishing shaped elements consisting of zinc or zinc alloys |
Country Status (10)
Country | Link |
---|---|
BE (1) | BE872979A (en) |
CH (1) | CH642111A5 (en) |
DE (1) | DE2757592C2 (en) |
DK (1) | DK155530C (en) |
FR (1) | FR2412622A1 (en) |
GB (1) | GB2038371B (en) |
IE (1) | IE47623B1 (en) |
IT (1) | IT1101329B (en) |
LU (1) | LU80710A1 (en) |
NL (1) | NL175079C (en) |
Families Citing this family (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE19636370B4 (en) * | 1996-09-09 | 2005-04-14 | Rheinzink Gmbh | Process for the production of protective coatings on flat products of titanium zinc and flat products |
DE19905134A1 (en) * | 1999-02-09 | 2000-09-28 | Hillebrand Walter Gmbh & Co Kg | Passivation process |
DE10156475A1 (en) * | 2001-11-16 | 2003-06-05 | Rheinzink Gmbh | Process for the production of dark protective layers on flat products made of titanium zinc |
US7611588B2 (en) | 2004-11-30 | 2009-11-03 | Ecolab Inc. | Methods and compositions for removing metal oxides |
CN101831661A (en) * | 2010-04-01 | 2010-09-15 | 中国科学院宁波材料技术与工程研究所 | Zinc alloy acid-washing solution and zinc alloy acid-washing treating process |
DE102010025707A1 (en) | 2010-06-30 | 2012-01-05 | Rheinzink Gmbh & Co. Kg | Process for the preparation of protective coatings on flat titanium zinc products |
HUE048799T2 (en) | 2013-10-31 | 2020-08-28 | Umicore Building Products France | Patterned rolled zinc alloy sheet |
CN112708896A (en) * | 2020-11-24 | 2021-04-27 | 清远先导材料有限公司 | Pickling process of ultra-pure zinc block |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2559878A (en) * | 1948-12-29 | 1951-07-10 | Western Electric Co | Zinc and cadmium passivating bath |
US2904413A (en) * | 1954-06-23 | 1959-09-15 | Jervis Corp | Process of bright dipping zinc base alloys |
US2884350A (en) * | 1955-12-28 | 1959-04-28 | Sylvania Electric Prod | Solderable zinc alloy coating |
US3524817A (en) * | 1966-11-02 | 1970-08-18 | Macdermid Inc | Method and compositions for chemically polishing zinc |
JPS4926422A (en) * | 1972-07-12 | 1974-03-08 |
-
1977
- 1977-12-23 DE DE2757592A patent/DE2757592C2/en not_active Expired
-
1978
- 1978-11-24 NL NLAANVRAGE7811555,A patent/NL175079C/en not_active IP Right Cessation
- 1978-12-12 FR FR7834905A patent/FR2412622A1/en active Granted
- 1978-12-21 BE BE6046709A patent/BE872979A/en not_active IP Right Cessation
- 1978-12-21 CH CH1304278A patent/CH642111A5/en not_active IP Right Cessation
- 1978-12-21 IT IT31109/78A patent/IT1101329B/en active
- 1978-12-21 GB GB7849629A patent/GB2038371B/en not_active Expired
- 1978-12-21 IE IE2551/78A patent/IE47623B1/en unknown
- 1978-12-22 LU LU80710A patent/LU80710A1/en unknown
- 1978-12-22 DK DK579178A patent/DK155530C/en not_active IP Right Cessation
Also Published As
Publication number | Publication date |
---|---|
IT7831109A0 (en) | 1978-12-21 |
NL7811555A (en) | 1979-06-26 |
DE2757592A1 (en) | 1979-07-05 |
DK155530C (en) | 1989-09-04 |
FR2412622B1 (en) | 1983-09-23 |
GB2038371A (en) | 1980-07-23 |
FR2412622A1 (en) | 1979-07-20 |
IT1101329B (en) | 1985-09-28 |
NL175079C (en) | 1984-09-17 |
DE2757592C2 (en) | 1985-03-28 |
DK155530B (en) | 1989-04-17 |
DK579178A (en) | 1979-06-24 |
BE872979A (en) | 1979-06-21 |
NL175079B (en) | 1984-04-16 |
CH642111A5 (en) | 1984-03-30 |
GB2038371B (en) | 1982-07-14 |
IE782551L (en) | 1979-06-23 |
LU80710A1 (en) | 1979-04-13 |
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