CA2172613C - Process for the galvanic application of a surface coating - Google Patents
Process for the galvanic application of a surface coating Download PDFInfo
- Publication number
- CA2172613C CA2172613C CA002172613A CA2172613A CA2172613C CA 2172613 C CA2172613 C CA 2172613C CA 002172613 A CA002172613 A CA 002172613A CA 2172613 A CA2172613 A CA 2172613A CA 2172613 C CA2172613 C CA 2172613C
- Authority
- CA
- Canada
- Prior art keywords
- current density
- current
- growth
- waveform
- component
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/60—Electroplating characterised by the structure or texture of the layers
- C25D5/625—Discontinuous layers, e.g. microcracked layers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B08—CLEANING
- B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
- B08B17/00—Methods preventing fouling
- B08B17/02—Preventing deposition of fouling or of dust
- B08B17/06—Preventing deposition of fouling or of dust by giving articles subject to fouling a special shape or arrangement
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B08—CLEANING
- B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
- B08B17/00—Methods preventing fouling
- B08B17/02—Preventing deposition of fouling or of dust
- B08B17/06—Preventing deposition of fouling or of dust by giving articles subject to fouling a special shape or arrangement
- B08B17/065—Preventing deposition of fouling or of dust by giving articles subject to fouling a special shape or arrangement the surface having a microscopic surface pattern to achieve the same effect as a lotus flower
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/18—Electroplating using modulated, pulsed or reversing current
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/60—Electroplating characterised by the structure or texture of the layers
- C25D5/605—Surface topography of the layers, e.g. rough, dendritic or nodular layers
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/627—Electroplating characterised by the visual appearance of the layers, e.g. colour, brightness or mat appearance
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Electroplating Methods And Accessories (AREA)
- Application Of Or Painting With Fluid Materials (AREA)
- Electroplating And Plating Baths Therefor (AREA)
Abstract
The invention relates to a galvanic coating process to provide a structured surface coating on a workpiece with an electrically conductive surface and a device for implementing the process. Here, the object to be coated is the cathode in a galvanic bath. The process current is raised in steps during a nucleation phase (10, 11) in which the stepwise increase in the current results in the formation of a deposit of individual or adjacent bodies on the surface of the object. The prooess current is then kept constant during a ramp working period (12), resulting in the growth of the previously produced nuclei or bodies. The process may be cyclically repeated.
Description
WU H5/UNN3t3 ' ' 1 71 TITLE: PROCESS FOR THE GALVANIC APPLICATION OF A SURFACE
COATING
DESCRIPTION
The invention relates to a process for the electrochemical (galvanic) application of a surface coating according to the German application with the file number DE 42 11 881.6-24, published Oct. 14, 1993.
Such surface structures are obtained more or less satisfactorily by chemical etching processes after coating or by mechanical machining processes such as grinding or sand-blasting. A hard-chromium layer is then applied to the thus created surface structure. these various working steps required for generation are elaborate and require a complex process technology.
The costs are essentially determined by the mechanical or chemical processing steps for generation of the structure.
In the field of the structuring of metal layers, use is made also of elaborate and very difficult-to-control dispersion-deposition processes in which a specific surface structure is obtained through organic or inorganic foreign substances which are included, for example, in a chromium layer and/or which block the growth of the chromium layer during the deposition process, with the result that rough surfaces are produced. The 2 0 foreign substances are present in the form of dispergate in the electrolyte.
German Application DE, 33 07 748, published Sept. 15, 1983, relates to a process for electrochemical coating in which a pulse-like current is used for nucleation. If a suitable current density is used, the resulting nuclei form a dendritic structure. It is thus possible in one working operation to generate rough, dendritically structure surfaces. The current density is understood to be the mean current density at the cathode surface.
The object of the invention is to create an improved process for the electrochemical application of structured metal layers - said process not requiring mechanical or chemical aftertreatments and allowing the 3 0 generation of diverse .>tructured metal layers - as well as to create a device for the implementation of said process.
W U H5 / UNN3ti -1a-The object of the invention is achieved according to the features of the characterizing parts of the claims.
The structured layer is applied directly by galvanic means to the object that is to be coated. For this purpose, said object must have an electrically conductive surface which, usually, has been ground in order to provide a smooth base for the structured layer. Prior to the coating process, the object is cleaned and degreased according to conventional electro-deposition practice. Said object is immersed as the cathode into a galvanic bath in which there is also an anode. The distance between anode and cathode is usually in the range between 1 and 40 cm. The following are preferably used as electrolyte: chromium electrolytes, particularly sulphuric chromium electrolytes, nitrosulphuric chromium electrolytes or alloying electrolytes.
A process voltage may be applied between anode and cathode and the flowing current causes a coating of material on the object to be coated, which is used as the cathode.
The invention proposes that positive current steps be applied in order to form nuclei.
The process of structure generation consists of a nucleation phase and a nucleus-growth phase. First of all, in the nucleation phase, process voltage and process current are increased in a plurality of steps from a starting value to a structure current density with in each case a predeterrninable change in the current density of 1 to 6 mA/cm2 per step. The starting value is 0 mA/cm2, but it may also be higher if the nucleation phase directly follows a precedinf; galvanic process phase and the current is not lowered in between to zero. The time between two current-density increases is approximately 0.1 to 30 seconds. Most frequently, intervals between steps of approximately 7 seconds are employed. New nuclei are formed with each current step. In contrast to pulse-current coating, the process current in this case does not fall back to zero after each positive step, but is further increased with each current step. This makes it possible, in particular, for more roundly and more uniformly shaped nuclei or bodies to be deposited on the object than is possible with the known pulse-current processes. The current steps are applied to the bath in such a number until a structured layer consisting of a deposit of individual or adjacent, approximately spherical or dendritic bodies is obtained on the surface of the object.
Preferably, a structured-layer thickness of 4 pm to 10 pm is desired with the nucleation phase. Usually, this necessitates between 10 and 240 current steps, particularly good results being obtained with SO to 60 steps.
The current density obtained after completion of the last current step is the structure current density. The reaclung of said structure current density largely signals the completion of the nucleation phase, the actual formation of the structure. The buildup of the resulting structure is dependent on many parameters, above all on the selected structure current density, thc: number, magnitude and time interval of the current steps, the bath temperature and tlhe electrolyte used. The current density per step as well as the time between two current-density increases can be changed during the nucleation phase. Depending on the nature of t:he current function, it is possible to produce different surface structures which are mainly characterized by different peak-to-valley heights. The ideal process parameters can be established simply by empirical means.
Usually, it can be said that, given a higher bath temperature and a higher acid content of the electrolyte, a greater structure current density is also employed.
Usually, said structure current density is two to three times the current density used in the case of normal direct-current coating. Direct-current coating employs current densities in the range from 1 S to 60 rnA/cm2, the value of the current density being dependent on the electrolylte and on the bath temperature. In the case of structure coating, current densities in the range from 30 to 180 mA/cm2 are possible.
Next comes the nucleus-growth phase, a process current with a current density in the range from 80% to 120% of the structure current density being applied during a predeterminable ramp working period. An approximately uniform current flows during the ramp working period; this leads to the growth.of the structure produced on the object. Depending on the duration of the ramp working period, said structure layer may be more or less heavily pronounced. Growth takes place faster at the highest points of the structure layer than at the low points between the bodies deposited in the nucleation phase. This results, initially, in a further increase in the roughness during the nucleus-growth phase. The ramp working period is usually in a range from 1 to seconds, preferably being approximately 30 seconds.
After expiration of the ramp working period, the process current is lowered to an end value, frequently to zero. 7.'his lowering of the process current to the end value may occur abn,~ptly; however, a ramp-like lowering is also possible. Here too, good results have been obtained with stepwise changing of the process current, the current steps preferably being in a range from -1 to -8 mA/cmz per step and the time between two current steps preferably being in the range from 0.1 to 1 second.
Hereinbefore, three proces:c steps have been described: the stepwise increasing of the process current during the nucleation phase up to the reaching of the structure current density; the holding ofthe process current in the range of the structure current density during the ramp working period (nucleus-growth phase); and the subsequent lowering of the process current to an end value. These process steps represent a structure-generation cycle. They ma_y be cyclically repeated. This is of particular advantage in cases in which heavier structuring of the surface is desired. In this connection, the end value of the preceding cycle corresponds to the starting value of the following cycle.
The number of repetitions, is dependent on the desired surface structure and layer thickness. Good results have been obtained with repetitions between two and twenty times. The end values of the individual cycles may differ in magnitude.
COATING
DESCRIPTION
The invention relates to a process for the electrochemical (galvanic) application of a surface coating according to the German application with the file number DE 42 11 881.6-24, published Oct. 14, 1993.
Such surface structures are obtained more or less satisfactorily by chemical etching processes after coating or by mechanical machining processes such as grinding or sand-blasting. A hard-chromium layer is then applied to the thus created surface structure. these various working steps required for generation are elaborate and require a complex process technology.
The costs are essentially determined by the mechanical or chemical processing steps for generation of the structure.
In the field of the structuring of metal layers, use is made also of elaborate and very difficult-to-control dispersion-deposition processes in which a specific surface structure is obtained through organic or inorganic foreign substances which are included, for example, in a chromium layer and/or which block the growth of the chromium layer during the deposition process, with the result that rough surfaces are produced. The 2 0 foreign substances are present in the form of dispergate in the electrolyte.
German Application DE, 33 07 748, published Sept. 15, 1983, relates to a process for electrochemical coating in which a pulse-like current is used for nucleation. If a suitable current density is used, the resulting nuclei form a dendritic structure. It is thus possible in one working operation to generate rough, dendritically structure surfaces. The current density is understood to be the mean current density at the cathode surface.
The object of the invention is to create an improved process for the electrochemical application of structured metal layers - said process not requiring mechanical or chemical aftertreatments and allowing the 3 0 generation of diverse .>tructured metal layers - as well as to create a device for the implementation of said process.
W U H5 / UNN3ti -1a-The object of the invention is achieved according to the features of the characterizing parts of the claims.
The structured layer is applied directly by galvanic means to the object that is to be coated. For this purpose, said object must have an electrically conductive surface which, usually, has been ground in order to provide a smooth base for the structured layer. Prior to the coating process, the object is cleaned and degreased according to conventional electro-deposition practice. Said object is immersed as the cathode into a galvanic bath in which there is also an anode. The distance between anode and cathode is usually in the range between 1 and 40 cm. The following are preferably used as electrolyte: chromium electrolytes, particularly sulphuric chromium electrolytes, nitrosulphuric chromium electrolytes or alloying electrolytes.
A process voltage may be applied between anode and cathode and the flowing current causes a coating of material on the object to be coated, which is used as the cathode.
The invention proposes that positive current steps be applied in order to form nuclei.
The process of structure generation consists of a nucleation phase and a nucleus-growth phase. First of all, in the nucleation phase, process voltage and process current are increased in a plurality of steps from a starting value to a structure current density with in each case a predeterrninable change in the current density of 1 to 6 mA/cm2 per step. The starting value is 0 mA/cm2, but it may also be higher if the nucleation phase directly follows a precedinf; galvanic process phase and the current is not lowered in between to zero. The time between two current-density increases is approximately 0.1 to 30 seconds. Most frequently, intervals between steps of approximately 7 seconds are employed. New nuclei are formed with each current step. In contrast to pulse-current coating, the process current in this case does not fall back to zero after each positive step, but is further increased with each current step. This makes it possible, in particular, for more roundly and more uniformly shaped nuclei or bodies to be deposited on the object than is possible with the known pulse-current processes. The current steps are applied to the bath in such a number until a structured layer consisting of a deposit of individual or adjacent, approximately spherical or dendritic bodies is obtained on the surface of the object.
Preferably, a structured-layer thickness of 4 pm to 10 pm is desired with the nucleation phase. Usually, this necessitates between 10 and 240 current steps, particularly good results being obtained with SO to 60 steps.
The current density obtained after completion of the last current step is the structure current density. The reaclung of said structure current density largely signals the completion of the nucleation phase, the actual formation of the structure. The buildup of the resulting structure is dependent on many parameters, above all on the selected structure current density, thc: number, magnitude and time interval of the current steps, the bath temperature and tlhe electrolyte used. The current density per step as well as the time between two current-density increases can be changed during the nucleation phase. Depending on the nature of t:he current function, it is possible to produce different surface structures which are mainly characterized by different peak-to-valley heights. The ideal process parameters can be established simply by empirical means.
Usually, it can be said that, given a higher bath temperature and a higher acid content of the electrolyte, a greater structure current density is also employed.
Usually, said structure current density is two to three times the current density used in the case of normal direct-current coating. Direct-current coating employs current densities in the range from 1 S to 60 rnA/cm2, the value of the current density being dependent on the electrolylte and on the bath temperature. In the case of structure coating, current densities in the range from 30 to 180 mA/cm2 are possible.
Next comes the nucleus-growth phase, a process current with a current density in the range from 80% to 120% of the structure current density being applied during a predeterminable ramp working period. An approximately uniform current flows during the ramp working period; this leads to the growth.of the structure produced on the object. Depending on the duration of the ramp working period, said structure layer may be more or less heavily pronounced. Growth takes place faster at the highest points of the structure layer than at the low points between the bodies deposited in the nucleation phase. This results, initially, in a further increase in the roughness during the nucleus-growth phase. The ramp working period is usually in a range from 1 to seconds, preferably being approximately 30 seconds.
After expiration of the ramp working period, the process current is lowered to an end value, frequently to zero. 7.'his lowering of the process current to the end value may occur abn,~ptly; however, a ramp-like lowering is also possible. Here too, good results have been obtained with stepwise changing of the process current, the current steps preferably being in a range from -1 to -8 mA/cmz per step and the time between two current steps preferably being in the range from 0.1 to 1 second.
Hereinbefore, three proces:c steps have been described: the stepwise increasing of the process current during the nucleation phase up to the reaching of the structure current density; the holding ofthe process current in the range of the structure current density during the ramp working period (nucleus-growth phase); and the subsequent lowering of the process current to an end value. These process steps represent a structure-generation cycle. They ma_y be cyclically repeated. This is of particular advantage in cases in which heavier structuring of the surface is desired. In this connection, the end value of the preceding cycle corresponds to the starting value of the following cycle.
The number of repetitions, is dependent on the desired surface structure and layer thickness. Good results have been obtained with repetitions between two and twenty times. The end values of the individual cycles may differ in magnitude.
Advantageously, the object tc> be coated is immersed in the bath some time, preferably one minute, prior to the start of the process. This waiting time serves above all for the purpose of temperature equalization; that is, the base material assumes approximately the temperature of the electrolyte.
Good results are obtained if, prior to the application of the structured layer, a direct-current base layer is applied under the conditions customary for normal chromium-plating. This is achieved in that, at the commencement of coating, a basic pulse (voltage or current pulse) is applied, a current density of 15 to 60 mAlcm2 being employed, this corresponding to the current values customary in the case of normal chromium-plating. Said basic pulse has a duration of approximately 600 seconds. In order to eliminate changes in concentration through the preceding direct-current treatment in the phase boundary layer prior to generation of the structure, it is advantageous if, after the basic pulse and prior to commencement of the generation of the structure, a current-free interval of approximately 60 seconds is added.
This process is required in many areas of technology for components with special surface characteristics. It is known to apply surface coatings to components by means of galvanic processes. Frequently, there are defined requirements with regard to the surface structure of the coai:ed workpiece. For example, cylinder bearing surfaces are required to have defined lubricant-storage locations for holding lubricants, and medical or optical equipment is requiired to have surfaces with a low reflection factor. Defined reflection factors are also required for functional and decorative applications in the furniture and sanitary-fittings industries. In the graphics industry, damping distributor rollers with a special, "rough" surface are required for printing presses. In the field of forming technology, structure-chromium-plated tools may be used in order to provide the workpiece with a structured surface. For example, the surface of sheet metal may be structured by rolling with structure-chromium-plated rolls.
The device for implementing the described process consists of a galvanic bath, said bath containing an electrolytic bath solution containing a metal concentration. The following are preferably used as electrolyte: chromium electrolytes, particularly sulphuric chromium electrolytes, nitrosulphuric chromium electrolytes or alloying electrolytes. A preferred electrolyte has a concentration of 180 to 300 grams of chromic acid Cr03 per litre. Added thereto may be foreign additions such as sulphuric acid HZS04, hydrofluoric acid HZFZ, silicofluoric acid HZSiF6 and mixtures thereof. A
preferred electrolyte contains 1 to 3._'i grams of sulphuric acid HZS04 per litre. The galvanic bath is usually heated, the temperature of the electrolyte preferably being 30 to 55 degrees Celsius.
Good results are obtained if, prior to the application of the structured layer, a direct-current base layer is applied under the conditions customary for normal chromium-plating. This is achieved in that, at the commencement of coating, a basic pulse (voltage or current pulse) is applied, a current density of 15 to 60 mAlcm2 being employed, this corresponding to the current values customary in the case of normal chromium-plating. Said basic pulse has a duration of approximately 600 seconds. In order to eliminate changes in concentration through the preceding direct-current treatment in the phase boundary layer prior to generation of the structure, it is advantageous if, after the basic pulse and prior to commencement of the generation of the structure, a current-free interval of approximately 60 seconds is added.
This process is required in many areas of technology for components with special surface characteristics. It is known to apply surface coatings to components by means of galvanic processes. Frequently, there are defined requirements with regard to the surface structure of the coai:ed workpiece. For example, cylinder bearing surfaces are required to have defined lubricant-storage locations for holding lubricants, and medical or optical equipment is requiired to have surfaces with a low reflection factor. Defined reflection factors are also required for functional and decorative applications in the furniture and sanitary-fittings industries. In the graphics industry, damping distributor rollers with a special, "rough" surface are required for printing presses. In the field of forming technology, structure-chromium-plated tools may be used in order to provide the workpiece with a structured surface. For example, the surface of sheet metal may be structured by rolling with structure-chromium-plated rolls.
The device for implementing the described process consists of a galvanic bath, said bath containing an electrolytic bath solution containing a metal concentration. The following are preferably used as electrolyte: chromium electrolytes, particularly sulphuric chromium electrolytes, nitrosulphuric chromium electrolytes or alloying electrolytes. A preferred electrolyte has a concentration of 180 to 300 grams of chromic acid Cr03 per litre. Added thereto may be foreign additions such as sulphuric acid HZS04, hydrofluoric acid HZFZ, silicofluoric acid HZSiF6 and mixtures thereof. A
preferred electrolyte contains 1 to 3._'i grams of sulphuric acid HZS04 per litre. The galvanic bath is usually heated, the temperature of the electrolyte preferably being 30 to 55 degrees Celsius.
An anode and a cathode are immersed into the electrolytic bath solution, the object to be coated forming the cathode or at least part of the cathode. If a chromium electrolyte is used, platinized platinum or PbSn7 is preferably used as the anode material. Anode and cathode are connected to an apparatus for supplying a process current. The process current can be increased from the starting value to the structure current density in a plurality of steps with in each case a predeterminable change in the current density of 1 to 6 mA/cm2 per step. The time intervals between two current increases can be set between 0.1 and 30 seconds. After the structure current density has been reached, a process current with a current density in the range of 80%
to 120% of the structure cun-ent density can be applied for a predeterminable ramp working period. In order to obtain uniform coating, the device may be furnished with a rotary drive for continuous rotation of the object. The distance between the anode and the object to be coated is in the range of 1 to 40 cm, preferably 25 cm.
Hereinbelow, the invention is described in greater detail in the following specimen embodiments with reference, to the drawings, in which:
Fig. 1 shows a schematic representation of a device for the galvanic application of structured layers;
Fig. 2 shows a graplhic representation of the current density with respect to time during the production of a structured layer;
Fig. 3 shows a photographic image on the scale 200:1 of the surface structure of an object, coated by the process described with reference to Fig. 2;
Fig. 4 shows a photographic image on the scale 500:1 of the surface structure shown in Fig. 3;
Fig. 5 shows a graphic representation of the current density with respect to time during the production of a structured layer;
Fig. 6 shows a graphic representation of the current density with respect to time during the production of a structured layer; and Fig. 7 shows a graphic representation of the current density with respect to time during the production of a structured layer.
Fig. 1 shows the schematic; representation of a device for the galvanic application of structured layers. The galvanic bath is formed by a tank filled with electrolytic liquid 1. Immersed into the galvanic bath are an object 2 to be coated and an anode 3. The object to be coated forms the cathode 2. Anode and cathode are connected to a controlled electric energy source 4. The energy source may be a current source or a voltage source. Since, as far as the electrical influences are concerned, the current or the current density at the cathode is decisive with regard to coating, the process can be controlled more precisely with a current source. Conversely, the use of a voltage source has the advantage of a less complex electrical circuitry. As long as other parameters, such as the bath temperature and the concentration of the electrolyte, do not undergo major change, it is also possible for the process to be efficiently controlled with a voltage source.
The electric energy source 4 is controlled by a programmable control unit 5.
The control unit makes it possible to specify any desired variations of the voltage or current with respect to time, tike voltage or current then automatically being applied to the electrodes via the energy source 4.
Fig. 2 shows the graphic representation of the process current density with respect to time during the production of a structured layer. The horizontal axis in Fig.
2 is the time axis, the current density being shown on the vertical axis y. Fig. 2 shows an example of a possible process which is to be described in greater detail in the following. Fig. 3 and 4 show photographic representations of the structured layer produced by said process.
Used as the galvanic bath its a sulphuric chromium electrolyte with 200 grams of chromic acid Cr03 and 2 grams of sulphuric acid HZSO,. The workpiece that is to be coated is a rotationally symmetrical component, a damping distributor roller for the printing industry. In order to create a suitable starting surface for the structure chromium-plating, the cylinder, consisting of St52, is first of all finely ground, with a peak-to-valley height of Rz; < 3 p.m. Subsequently, a 30 pm thick nickel layer and, thereon, a 10 wm thick, low-crack chromium layer are applied according to the conditions customary in the field of electro-deposition. For structure chromium-plating, the thus prepared workpiece is rotated in the galvanic bath in order to obtain as uniform a coating as possible. The workpie:ce forms the cathode; platinized titanium or PbSn7 is used as the anode. The electrode distance between anode and cathode is set to 25 cm.
During a first process phase 7, the process current remains off. This phase serves to acclimatize the workpiece; to the galvanic bath, the workpiece assuming the temperature of the electrolyte. After approximately one minute, a direct current between anode and cathode: is switched on. Said current remains on during phase 8, which lasts approximately 600 seconds, a chromium direct-current base layer being applied to the workpiece. The current density used is also usual for normal chromium-plating, in this case 20 mA/cm2. After the direct-current base layer has been applied, there follows a second phase: 9 without current.
Thereafter, the actual production of the structure commences. During phases 10 and 11, the current density is increased in steps to the structure current density 14. The technical characteristics of the steps {magnitude of the current steps and time interval between two current steps) are varied during the increase. In the first phase 10, the current is increased in 16 steps to 40 mA/cmz. This corresponds to a change in the current density of 2.5 mA/cm2 per step. The time 28 between two current steps is 5 seconds. Thereafter, during phase 11, the current density is increased in 62 further steps to the structure current density of 100 mAlcm2; the time between two current steps is 6 seconds (the variation in current density shown in the graph in Fig. 2 is not to scale; the same applies to the graphs shown in Fig. S and 6).
After the structure current density has been reached, said current density is held during the ramp working period 12. The thereby flowing direct current leads to the growth of the structured layer produced in phases 10 and 11. The duration of the ramp working period is 60 seconds. Thereafter, the current density is once again lowered step by step, in 22 steps, to the end value of 0 mAJcm2, the time between two current steps being 4 seconds.
For application-related reasons, in the case of the damping distributor roller, a 4 to 8 um thick micro-cracked cl'~romium layer is subsequently applied to the chromium structured layer produced by the process according to the invention. The application of said micro-cracked chromium layer is earned out under the direct-current conditions customary for el~ectro-deposition and is not described in any greater detail here.
Fig. 3 and 4 show microscopic photographs of the chromium structured layer produced by the process described with reference to Fig. 2. The structured layer consists predominantly of approximately spherical, individual and partially adjacent bodies. The structured layer shown has a surface roughness of Rz=8 pm with a percentage of contact area of25%. The "percentage of contact area" is also defined as "percentage of material°' according to :DIN 4762.
Fig. 5 shows the variation in current density with respect to time for a further structured-coating process. The process phases 7, 8 and 9 have already been discussed in the remarks with reference to Fig. 2. In the thereafter following phase 15, the -8_ current density is increased in 110 equal steps to the structure current density of 100 mAlcm2: The time between two current steps is 10 seconds. After the ramp working period 16 of 60 seconds, the current density is lowered, this time in 22 equal steps, to the end value of 0 mA/crn2. The time between two current steps is 4 seconds.
Thereafter, following a short current-free moment, the process cycle, consisting of phases 15, 16 and 17, is repeated.
Fig. 6 shows the variation in current density with respect to time for a further process-After the waiting phase 7 for the acclimatization of the workpiece to the galvanic bath, there follows a direct-current impulse 18, which is identical in nature to the direct-current impulse 8 in Fig. 2. Thereafter, there directly follows a nucleation phase 19, in which the current density is increased step by step to the structure current density 24.
The current density is then held at the structure current density during the ramp working period 20 and is subsequently lowered during phase 21 in ramp-like manner to a final value 26. After a short waiting time 22, there again follows a nucleation phase 23 with stepwise increase of the current density to the new structure current density 25, the starting current density of the nucleation phase 23 being identical to the end value 26 to which the current density was lowered at the end of the preceding structure-producing cycle. :During the ramp working period 27, the current density is then held at the structure current density 25 and, thereafter, is lowered in steps to the new end value of 0 mA/cmz.
Fig. 7 shows the variation in current density with respect to time for a further variant of the process. The process stages 7 to 9 have already been discussed with reference to Fig. 2. The process current is then increased step by step to the structure current density 30 during phase 29. Thereafter, during the ramp working period 32, a process current with a current-density value of 80% of the structure current density 30 is applied. In between, there is a current-free rest period 31. After expiration of the ramp working period 32, the process current is lowered during phase 33 to an end value.
Said end value serves as the starting value for a second structure-producing cycle, beginning with the stepwise rise in current in phase 35. After the new structure current density 36 has been reached, a process current with a current-density value of 120%
of the structure current density 36 is applied during the ramp working period 38. In between, there is once again a current-free rest period 37.
to 120% of the structure cun-ent density can be applied for a predeterminable ramp working period. In order to obtain uniform coating, the device may be furnished with a rotary drive for continuous rotation of the object. The distance between the anode and the object to be coated is in the range of 1 to 40 cm, preferably 25 cm.
Hereinbelow, the invention is described in greater detail in the following specimen embodiments with reference, to the drawings, in which:
Fig. 1 shows a schematic representation of a device for the galvanic application of structured layers;
Fig. 2 shows a graplhic representation of the current density with respect to time during the production of a structured layer;
Fig. 3 shows a photographic image on the scale 200:1 of the surface structure of an object, coated by the process described with reference to Fig. 2;
Fig. 4 shows a photographic image on the scale 500:1 of the surface structure shown in Fig. 3;
Fig. 5 shows a graphic representation of the current density with respect to time during the production of a structured layer;
Fig. 6 shows a graphic representation of the current density with respect to time during the production of a structured layer; and Fig. 7 shows a graphic representation of the current density with respect to time during the production of a structured layer.
Fig. 1 shows the schematic; representation of a device for the galvanic application of structured layers. The galvanic bath is formed by a tank filled with electrolytic liquid 1. Immersed into the galvanic bath are an object 2 to be coated and an anode 3. The object to be coated forms the cathode 2. Anode and cathode are connected to a controlled electric energy source 4. The energy source may be a current source or a voltage source. Since, as far as the electrical influences are concerned, the current or the current density at the cathode is decisive with regard to coating, the process can be controlled more precisely with a current source. Conversely, the use of a voltage source has the advantage of a less complex electrical circuitry. As long as other parameters, such as the bath temperature and the concentration of the electrolyte, do not undergo major change, it is also possible for the process to be efficiently controlled with a voltage source.
The electric energy source 4 is controlled by a programmable control unit 5.
The control unit makes it possible to specify any desired variations of the voltage or current with respect to time, tike voltage or current then automatically being applied to the electrodes via the energy source 4.
Fig. 2 shows the graphic representation of the process current density with respect to time during the production of a structured layer. The horizontal axis in Fig.
2 is the time axis, the current density being shown on the vertical axis y. Fig. 2 shows an example of a possible process which is to be described in greater detail in the following. Fig. 3 and 4 show photographic representations of the structured layer produced by said process.
Used as the galvanic bath its a sulphuric chromium electrolyte with 200 grams of chromic acid Cr03 and 2 grams of sulphuric acid HZSO,. The workpiece that is to be coated is a rotationally symmetrical component, a damping distributor roller for the printing industry. In order to create a suitable starting surface for the structure chromium-plating, the cylinder, consisting of St52, is first of all finely ground, with a peak-to-valley height of Rz; < 3 p.m. Subsequently, a 30 pm thick nickel layer and, thereon, a 10 wm thick, low-crack chromium layer are applied according to the conditions customary in the field of electro-deposition. For structure chromium-plating, the thus prepared workpiece is rotated in the galvanic bath in order to obtain as uniform a coating as possible. The workpie:ce forms the cathode; platinized titanium or PbSn7 is used as the anode. The electrode distance between anode and cathode is set to 25 cm.
During a first process phase 7, the process current remains off. This phase serves to acclimatize the workpiece; to the galvanic bath, the workpiece assuming the temperature of the electrolyte. After approximately one minute, a direct current between anode and cathode: is switched on. Said current remains on during phase 8, which lasts approximately 600 seconds, a chromium direct-current base layer being applied to the workpiece. The current density used is also usual for normal chromium-plating, in this case 20 mA/cm2. After the direct-current base layer has been applied, there follows a second phase: 9 without current.
Thereafter, the actual production of the structure commences. During phases 10 and 11, the current density is increased in steps to the structure current density 14. The technical characteristics of the steps {magnitude of the current steps and time interval between two current steps) are varied during the increase. In the first phase 10, the current is increased in 16 steps to 40 mA/cmz. This corresponds to a change in the current density of 2.5 mA/cm2 per step. The time 28 between two current steps is 5 seconds. Thereafter, during phase 11, the current density is increased in 62 further steps to the structure current density of 100 mAlcm2; the time between two current steps is 6 seconds (the variation in current density shown in the graph in Fig. 2 is not to scale; the same applies to the graphs shown in Fig. S and 6).
After the structure current density has been reached, said current density is held during the ramp working period 12. The thereby flowing direct current leads to the growth of the structured layer produced in phases 10 and 11. The duration of the ramp working period is 60 seconds. Thereafter, the current density is once again lowered step by step, in 22 steps, to the end value of 0 mAJcm2, the time between two current steps being 4 seconds.
For application-related reasons, in the case of the damping distributor roller, a 4 to 8 um thick micro-cracked cl'~romium layer is subsequently applied to the chromium structured layer produced by the process according to the invention. The application of said micro-cracked chromium layer is earned out under the direct-current conditions customary for el~ectro-deposition and is not described in any greater detail here.
Fig. 3 and 4 show microscopic photographs of the chromium structured layer produced by the process described with reference to Fig. 2. The structured layer consists predominantly of approximately spherical, individual and partially adjacent bodies. The structured layer shown has a surface roughness of Rz=8 pm with a percentage of contact area of25%. The "percentage of contact area" is also defined as "percentage of material°' according to :DIN 4762.
Fig. 5 shows the variation in current density with respect to time for a further structured-coating process. The process phases 7, 8 and 9 have already been discussed in the remarks with reference to Fig. 2. In the thereafter following phase 15, the -8_ current density is increased in 110 equal steps to the structure current density of 100 mAlcm2: The time between two current steps is 10 seconds. After the ramp working period 16 of 60 seconds, the current density is lowered, this time in 22 equal steps, to the end value of 0 mA/crn2. The time between two current steps is 4 seconds.
Thereafter, following a short current-free moment, the process cycle, consisting of phases 15, 16 and 17, is repeated.
Fig. 6 shows the variation in current density with respect to time for a further process-After the waiting phase 7 for the acclimatization of the workpiece to the galvanic bath, there follows a direct-current impulse 18, which is identical in nature to the direct-current impulse 8 in Fig. 2. Thereafter, there directly follows a nucleation phase 19, in which the current density is increased step by step to the structure current density 24.
The current density is then held at the structure current density during the ramp working period 20 and is subsequently lowered during phase 21 in ramp-like manner to a final value 26. After a short waiting time 22, there again follows a nucleation phase 23 with stepwise increase of the current density to the new structure current density 25, the starting current density of the nucleation phase 23 being identical to the end value 26 to which the current density was lowered at the end of the preceding structure-producing cycle. :During the ramp working period 27, the current density is then held at the structure current density 25 and, thereafter, is lowered in steps to the new end value of 0 mA/cmz.
Fig. 7 shows the variation in current density with respect to time for a further variant of the process. The process stages 7 to 9 have already been discussed with reference to Fig. 2. The process current is then increased step by step to the structure current density 30 during phase 29. Thereafter, during the ramp working period 32, a process current with a current-density value of 80% of the structure current density 30 is applied. In between, there is a current-free rest period 31. After expiration of the ramp working period 32, the process current is lowered during phase 33 to an end value.
Said end value serves as the starting value for a second structure-producing cycle, beginning with the stepwise rise in current in phase 35. After the new structure current density 36 has been reached, a process current with a current-density value of 120%
of the structure current density 36 is applied during the ramp working period 38. In between, there is once again a current-free rest period 37.
Claims (25)
PROPERTY OR PRIVILEGE, IS CLAIMED ARE DEFINED AS FOLLOWS:
1. An electrochemical process for depositing a surface coating on a component comprising placing the component in a galvanic bath and forming an electrical circuit with the component as a cathcode, powering the electrical circuit in a series of cycles using an electrical waveform that produces in each cycle an initial stage, a growth stage and a reset stage, where said initial stage promotes the formation of a plurality of island formations of deposited material on the surface of the component, said growth stage increases the size of the previously deposited island formations by the deposition of additional deposited material, and said reset stage reduces the current density of the waveform to an end value less than or equal to a start value for the next cycle, said waveform in said initial stage having the current density thereof increased in a plurality of steps with a waiting period between steps of 0.1 to 30 seconds, said waveform in said growth stage having current density to promote an increase in the size of the existing island formations by deposit of additional material.
2. A process as claimed in claim 1 wherein in said growth stage said current density is maintained.
3. A process a claimed in claim 1 or 2 wherein said process includes at least 20 cycles.
4. A process as claimed in claim 1, 2 or 3 wherein each step increases the density em amount in the range of 1 to 6 mA/cm2.
5. A process as claimed in claim 1, 2, 3 or 4 wherein said current density in said growth stage is 80% to 120% of the current density of the last step of the initial stage.
6. A process as claimed in claim 1, 2, 3, 4 or 5 wherein each step in said initial stage is of a duration of 3 to 7 seconds.
7. A process as claimed in claim 1, 2, 3, 4, 5 or 6 wherein the duration of said growth stage is less than 600 seconds.
8. A process as claimed in claim 1, 2, 3, 4, 5 or 6 wherein said growth stage is of a duration less than 30 seconds.
9. A process as claimed in claim 1, 2, 3, 4, 5, 6, 7 or 8 wherein the current density in said reset: stage is decreased in a series of steps where each step decreases the current density by a value in the range of -1 to -8 mA/cm2.
10. A process as claimed in claim 1, 2, 3, 4, 5, 6, 7, 8 or 9 used to form a surface coating on a cylinder for a printing press.
11. An improved process for electrochemically depositing a surface coating, wherein a component is subjected to a galvanic bath and the surface coating is deposited on the component with a structured outer surface topography, by forming a plurality of island formations of deposition material on a surface of the component by providing an electrical waveform as a source of electrical energy, and causing a growth of the deposition material on the plurality of island formations for forming the structured outer surface topography with a follow-up waveform as the source of electrical energy during a growth working period, the improvement which comprises:
increasing a strength of a current density of the electrical waveform during the step of forming the plurality of island formations in a plurality of steps with a waiting period between respective step increases of the plurality of steps of 0.1 to 30 seconds;
subsequently causing growth of the deposition material on the islands with a follow-up waveform having a current density during the growth working period;
decreasing the strength of said current density of the follow-up waveform to an end value after the growth working period; and cyclically repeating the afore-defined process steps utilizing the end value of a preceding cycle as a starting value of a respectively following cycle;
wherein the structured outer surface topography is formed without mechanical and chemical after treatment steps after a last growth step follow-up waveform has been removed.
increasing a strength of a current density of the electrical waveform during the step of forming the plurality of island formations in a plurality of steps with a waiting period between respective step increases of the plurality of steps of 0.1 to 30 seconds;
subsequently causing growth of the deposition material on the islands with a follow-up waveform having a current density during the growth working period;
decreasing the strength of said current density of the follow-up waveform to an end value after the growth working period; and cyclically repeating the afore-defined process steps utilizing the end value of a preceding cycle as a starting value of a respectively following cycle;
wherein the structured outer surface topography is formed without mechanical and chemical after treatment steps after a last growth step follow-up waveform has been removed.
12. The process according to claim 11, which comprises increasing the strength of the electrical waveform from the starting value to a structure current density, with a change in said current density of 1 to 6 mA/cm2 per step until a structured layer formed of a deposit of approximately spherical or dendritic bodies is obtained on the surface of the component, and subsequently, in an island growth phase lasting for the growth working period, applying a process current at a current density of between 80% and 120% of the structure current density.
13. The process according to claim 12, which comprises defining the structure current density in a range from 30 mA/ cm2 to 180 mA/cm2.
14. The process according to claim 12, which comprises defining the growth working period at between 1 and 600 sec.
15. The process according to claim 12, which comprises defining the growth working period at 30 sec.
16. The process according to claim 12, which further comprises decreasing the process currant to an end value which is different at the end of each of the cycles.
17. The process according to claim 11, wherein said wait period is approximately 7 sec.
18. The process according to claim 11, which comprises increasing said current density in 10 to 240 steps.
19. The process according to claim 11, which comprises, in the decreasing step, decreasing said current density step by step, with each decrease being between -1 and -8 mA/cm2 per step.
20. The process according to claim 11, which further comprises, prior to the increasing step, applying a direct-current waveform with a current density of 15 to 60 mA/cm2 for building a direct-current base layer on the surface of the component.
21. The process according to claim 11, wherein the component is a cylinder, and the process comprises forming a surface structure on lubricant-storage regions for holding lubricants on the cylinder.
22. The process according to claim 11, which further comprises forming a surface structure on the component for setting defined reflection factors of the surface structure.
23. A process for electrochemically depositing a structured surface coating on a machine component, which comprises:
a) connecting a machine component in a direct current loop and defining an electrical parameter as one of an electric voltage and electric current;
b) immersing the component in a galvanic bath;
c) subjecting the component to a starting waveform of the electrical parameter, for forming islands of deposition material on a surface of the component;
d) adjusting the current density of the starting waveform by increasing a strength of the current density during the step of forming the island deposition material in a plurality of steps with a waiting period between respective step increases of the plurality of steps of 0.1 to 30 seconds;
e) subsequently causing a growth of the deposition material on the islands with a follow-up waveform of the electrical parameter in a growth step;
f) adjusting the current density of the follow-up waveform by decreasing the electrical parameter to an end value; and g) cyclically repeating steps c) - f);
wherein the structured surface coating is formed without mechanical and chemical after treatment steps after a final growth step follow-up waveform has been removed.
a) connecting a machine component in a direct current loop and defining an electrical parameter as one of an electric voltage and electric current;
b) immersing the component in a galvanic bath;
c) subjecting the component to a starting waveform of the electrical parameter, for forming islands of deposition material on a surface of the component;
d) adjusting the current density of the starting waveform by increasing a strength of the current density during the step of forming the island deposition material in a plurality of steps with a waiting period between respective step increases of the plurality of steps of 0.1 to 30 seconds;
e) subsequently causing a growth of the deposition material on the islands with a follow-up waveform of the electrical parameter in a growth step;
f) adjusting the current density of the follow-up waveform by decreasing the electrical parameter to an end value; and g) cyclically repeating steps c) - f);
wherein the structured surface coating is formed without mechanical and chemical after treatment steps after a final growth step follow-up waveform has been removed.
24. The process according to claim 23, which comprises increasing the electrical parameter from a starting value to a structure current density, the steps each being an increase in current density of 1 to 6 mA/cm2 per step until a basic structure layer is formed on the component comprising a deposit layer of individual adjacent, approximately spherical or dendritic bodies; and subsequently, in the causing a growth step, maintaining a process current in the current loop with a current density in the range from 80% to 120% of the structure current density during a growth working period.
25. The process of claim 23 or 24 wherein said steps c) - f) are repeated between two and twenty tunes, and in repetition utilizing the end value of a preceding cycle as a starting value of a waveform of a following cycle.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP4334122.5 | 1993-10-07 | ||
| DE4334122A DE4334122C2 (en) | 1992-04-09 | 1993-10-07 | Process for electrochemically applying a surface coating and application of the process |
| PCT/EP1994/003314 WO1995009938A1 (en) | 1993-10-07 | 1994-10-01 | Process for the galvanic application of a surface coating |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2172613A1 CA2172613A1 (en) | 1995-04-13 |
| CA2172613C true CA2172613C (en) | 2003-06-17 |
Family
ID=6499571
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002172613A Expired - Fee Related CA2172613C (en) | 1993-10-07 | 1994-10-01 | Process for the galvanic application of a surface coating |
Country Status (17)
| Country | Link |
|---|---|
| EP (1) | EP0722515B1 (en) |
| JP (1) | JP3293828B2 (en) |
| KR (1) | KR100332077B1 (en) |
| CN (1) | CN1044395C (en) |
| AU (1) | AU7784794A (en) |
| BR (1) | BR9405631A (en) |
| CA (1) | CA2172613C (en) |
| CH (1) | CH690273A5 (en) |
| CZ (1) | CZ286909B6 (en) |
| DE (1) | DE59405190D1 (en) |
| ES (1) | ES2114703T3 (en) |
| FI (1) | FI103674B (en) |
| GR (1) | GR3026689T3 (en) |
| PL (1) | PL177073B1 (en) |
| SI (1) | SI9420006B (en) |
| SK (1) | SK281999B6 (en) |
| WO (1) | WO1995009938A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8110087B2 (en) | 2004-04-21 | 2012-02-07 | Federal-Mogul Burscheid Gmbh | Production of a structured hard chromium layer and production of a coating |
| US11136685B2 (en) | 2015-11-05 | 2021-10-05 | Topocrom Systems Ag | Method and device for the galvanic application of a surface coating |
Families Citing this family (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19828545C1 (en) * | 1998-06-26 | 1999-08-12 | Cromotec Oberflaechentechnik G | Galvanic bath for forming a hard chromium layer on machine parts |
| US6478943B1 (en) | 2000-06-01 | 2002-11-12 | Roll Surface Technologies, Inc. | Method of manufacture of electrochemically textured surface having controlled peak characteristics |
| CA2450283C (en) * | 2001-07-05 | 2008-10-28 | Roll Surface Technologies, Inc. | Electrochemically textured surface having controlled peak characteristics and the method of manufacture |
| DE10255853A1 (en) | 2002-11-29 | 2004-06-17 | Federal-Mogul Burscheid Gmbh | Manufacture of structured hard chrome layers |
| DE10302107A1 (en) * | 2003-01-21 | 2004-07-29 | Fuchs Technology Ag | cylinder surface |
| DE102008017270B3 (en) | 2008-04-04 | 2009-06-04 | Federal-Mogul Burscheid Gmbh | Structured chromium solid particle layer and method for its production and coated machine element |
| AT506076B1 (en) * | 2008-06-03 | 2009-06-15 | Vassilios Dipl Ing Polydoros | METHOD FOR PRODUCING NANOSTRUCTURED CHROMIUM LAYERS ON A SUBSTRATE |
| EP2149447A1 (en) | 2008-07-29 | 2010-02-03 | Alcan Technology & Management Ltd. | Method for producing a sheet of material with surface structure |
| CN102877098B (en) * | 2012-10-29 | 2015-06-17 | 东莞市若美电子科技有限公司 | Multi-waveband output pulse plating method |
| EP3000918B1 (en) * | 2014-09-24 | 2018-10-24 | topocrom systems AG | Method and device for the galvanic application of a surface coating |
| CN105734631B (en) * | 2014-12-10 | 2019-03-19 | 上海宝钢工业技术服务有限公司 | The electro-plating method of roll for cold rolling frosting treatment |
| CN110117802B (en) * | 2019-05-06 | 2020-05-22 | 浙江大学 | Preparation method of multistage three-dimensional microstructure |
| CN111962120A (en) * | 2020-08-18 | 2020-11-20 | 重庆佰鸿机械设备有限公司 | Pipe fitting inner wall surface treatment process |
| EP4012074A1 (en) | 2020-12-14 | 2022-06-15 | topocrom systems AG | Surface coating and method for the production thereof |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DD134785A1 (en) * | 1978-01-25 | 1979-03-21 | Hans Skilandat | METHOD FOR THE ELECTROLYTIC PRODUCTION OF A COPPER SHELF ON COPPER FOIL |
| US4468293A (en) * | 1982-03-05 | 1984-08-28 | Olin Corporation | Electrochemical treatment of copper for improving its bond strength |
| US5185073A (en) * | 1988-06-21 | 1993-02-09 | International Business Machines Corporation | Method of fabricating nendritic materials |
| DE4211881C2 (en) * | 1992-04-09 | 1994-07-28 | Wmv Ag | Process for the electrochemical application of a structured surface coating |
-
1994
- 1994-10-01 JP JP51061895A patent/JP3293828B2/en not_active Expired - Lifetime
- 1994-10-01 PL PL94309286A patent/PL177073B1/en not_active IP Right Cessation
- 1994-10-01 KR KR1019950702238A patent/KR100332077B1/en active IP Right Grant
- 1994-10-01 CZ CZ19951447A patent/CZ286909B6/en not_active IP Right Cessation
- 1994-10-01 EP EP94928407A patent/EP0722515B1/en not_active Expired - Lifetime
- 1994-10-01 AU AU77847/94A patent/AU7784794A/en not_active Abandoned
- 1994-10-01 SI SI9420006A patent/SI9420006B/en not_active IP Right Cessation
- 1994-10-01 ES ES94928407T patent/ES2114703T3/en not_active Expired - Lifetime
- 1994-10-01 DE DE59405190T patent/DE59405190D1/en not_active Expired - Lifetime
- 1994-10-01 CH CH01713/95A patent/CH690273A5/en not_active IP Right Cessation
- 1994-10-01 CA CA002172613A patent/CA2172613C/en not_active Expired - Fee Related
- 1994-10-01 SK SK861-95A patent/SK281999B6/en unknown
- 1994-10-01 CN CN94190766A patent/CN1044395C/en not_active Expired - Lifetime
- 1994-10-01 BR BR9405631-5A patent/BR9405631A/en not_active IP Right Cessation
- 1994-10-01 WO PCT/EP1994/003314 patent/WO1995009938A1/en active IP Right Grant
-
1995
- 1995-06-06 FI FI952774A patent/FI103674B/en active
-
1998
- 1998-04-21 GR GR980400886T patent/GR3026689T3/en unknown
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8110087B2 (en) | 2004-04-21 | 2012-02-07 | Federal-Mogul Burscheid Gmbh | Production of a structured hard chromium layer and production of a coating |
| US11136685B2 (en) | 2015-11-05 | 2021-10-05 | Topocrom Systems Ag | Method and device for the galvanic application of a surface coating |
| US11732373B2 (en) | 2015-11-05 | 2023-08-22 | Topocrom Systems Ag | Method and device for the galvanic application of a surface coating |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH09503550A (en) | 1997-04-08 |
| WO1995009938A1 (en) | 1995-04-13 |
| CZ286909B6 (en) | 2000-08-16 |
| CN1115583A (en) | 1996-01-24 |
| SI9420006A (en) | 1995-12-31 |
| AU7784794A (en) | 1995-05-01 |
| EP0722515B1 (en) | 1998-01-28 |
| CN1044395C (en) | 1999-07-28 |
| FI103674B1 (en) | 1999-08-13 |
| CA2172613A1 (en) | 1995-04-13 |
| SI9420006B (en) | 2002-02-28 |
| EP0722515A1 (en) | 1996-07-24 |
| FI103674B (en) | 1999-08-13 |
| SK86195A3 (en) | 1996-03-06 |
| BR9405631A (en) | 1999-09-08 |
| FI952774A (en) | 1995-06-06 |
| ES2114703T3 (en) | 1998-06-01 |
| KR100332077B1 (en) | 2002-10-31 |
| CZ144795A3 (en) | 1996-07-17 |
| FI952774A0 (en) | 1995-06-06 |
| SK281999B6 (en) | 2001-10-08 |
| PL309286A1 (en) | 1995-10-02 |
| DE59405190D1 (en) | 1998-03-05 |
| GR3026689T3 (en) | 1998-07-31 |
| CH690273A5 (en) | 2000-06-30 |
| JP3293828B2 (en) | 2002-06-17 |
| PL177073B1 (en) | 1999-09-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2172613C (en) | Process for the galvanic application of a surface coating | |
| US5415761A (en) | Process for applying a structured surface coating on a component | |
| US5958207A (en) | Process for applying a surface coating | |
| CA2730252C (en) | Low stress property modulated materials and methods of their preparation | |
| DE3046757C2 (en) | Gravure cylinder | |
| WO2003046262A1 (en) | Sequential electromachining and electropolishing of metals and the like using modulated electric fields | |
| US5853561A (en) | Method for surface texturing titanium products | |
| US3939046A (en) | Method of electroforming on a metal substrate | |
| WO2001018281A1 (en) | Rapid colouring process for aluminum products | |
| DE4334122C2 (en) | Process for electrochemically applying a surface coating and application of the process | |
| JPH03267400A (en) | Production of lithographic printing plate supporting body | |
| JP2002134858A (en) | Copper foil for printed boards | |
| EP2619354B1 (en) | Process for removing a coating from workpieces | |
| WO2002057515A3 (en) | A continuous electroforming process to form a strip for battery electrodes and a mandrel to be used in said electroforming process | |
| EP0276264B1 (en) | Process and device for electrochemically machining workpieces | |
| KR100499793B1 (en) | Electroless plating method | |
| JP2001342589A (en) | Method and apparatus for manufacturing copper foil | |
| WO1998003702A1 (en) | Method for obtaining a high surface finish on titanium based coatings | |
| Arrowsmith | Seeing is believing on surface treated aluminium | |
| JP2955968B2 (en) | Graphite electrolytic electrode | |
| JPH04136198A (en) | Method of electroplating | |
| JPH02254197A (en) | Anodizing method | |
| Banks | Method for Surface Texturing Titanium Products | |
| JPH1111035A (en) | Manufacture of aluminum supporting body for planographic printing plate | |
| RU99118450A (en) | METHOD OF ELECTROLYTIC CHROME |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |
Effective date: 20141001 |