Abstract: An electrolyte for the electrochemical machining of a ?-?? nickel-based superalloy, includes NaNO3 in a content of between 10% and 30% by weight relative to the total weight of the electrolyte; a complexing agent selected from sulfosalicylic acid at a pH of between 3 and 10 and nitrilotriacetic acid at a pH of between 7 and 14, the complexing agent being present in a content of between 1% and 5% by weight relative to the total weight of the electrolyte; optionally, an anionic surfactant in a content of between 1% and 5% by weight relative to the total weight of the electrolyte; optionally, NaOH in order to obtain the desired pH; and an aqueous solvent.

Abstract: Proposed is a method of recovering valuable metal from scrap containing conductive oxide including the steps of using an insoluble electrode as either an anode or a cathode, using a scrap containing conductive oxide as the counter cathode or anode, performing electrolysis while periodically inverting the polarity, and recovering the scrap as hydroxide. With the foregoing method of recovering valuable metal from scrap containing conductive oxide, oxide system scrap is conductive oxide and a substance that can be reduced to metal or suboxide with hydrogen. This method enables the efficient recovery of valuable metal from sputtering target scrap containing conductive oxide or scrap such as mill ends of conductive oxide that arise during the production of such a sputtering target.

Abstract: The invention relates to a ceramic implant, especially a dental implant, comprising a structured or porous surface for at least partially inserting into a bone. An especially advantageous surface is obtained when it is at least partially modified by a salt melt. These excellent osteointegration properties can be obtained by a method whereby the surface is modified in a salt melt at least in the regions exposed to the bones and/or soft tissue, optionally following a previous modification of the surface whereby material has been removed.

Abstract: The invention relates to a method for electrokinetic decontamination of a porous solid medium, which comprises: a) extracting the contaminating species present in the solid medium in an electrolyte appearing as an essentially inorganic gel, this extraction being obtained by applying an electric current between two electrodes positioned at the surface and/or in the interior of the solid medium, the contact of at least one of these electrodes with said solid medium being ensured by a layer of said gel, b) drying the gel containing the thereby extracted contaminating species until a dry residue is obtained which fractures, and c) removing the thereby obtained dry residue from said solid residue.

Abstract: The present invention relates to a fuel cell separator and a method of producing the fuel cell separator. A first separator and a second separator are provided as the fuel cell separators. Firstly, the first separator and the second separator are heated. Thus, an Fe rich layer is formed in a surface layer of each of the first separator and the second separator, and a Cr rich layer where a proportion of Cr is 60% or more is formed in an inner portion of each of the first separator and the second separator. Then, an electrolytic treatment is applied to each of the first separator and the second separator to remove the Fe rich layer. By the removal, the Cr rich layer is exposed to the outside on the outermost surface layer of each of the first separator and the second separator.

Abstract: A method of electrochemical dissolution of ruthenium-cobalt (Ru—Co)-based alloy is disclosed, in which a Ru—Co-based alloy bulk is subjected into an electrolyte solution comprising about 50 wt. % to 75 wt. % of sulfuric acid, thereby electrolyzing the Ru—Co-based alloy bulk and forming a product solution comprising Ru and Co ions in the electrolyte solution.

Abstract: Apparatus and methods for removing coatings from metal components, such as metal components used in aircraft and other aerospace vehicles and the oil industry, as well as aqueous bath compositions. The metal component may be DC coupled with a counter electrode and immersed in an aqueous bath that includes an active oxygen source and a ligand in a composition effective to remove the coating. The aqueous bath may include hydrogen peroxide as the active oxygen source and may be maintained in a specific pH range if the temperature of the aqueous bath is controlled. In an alternative embodiment, the composition of the aqueous bath may include a non-peroxide active oxygen source, such as sodium perborate, and be maintained in a different specific pH range. An oxygen sensor may be provided to periodically monitor the concentration of active oxygen in the aqueous bath.

Abstract: Hexavalent chrome is extracted from a film on a workpiece which film contains hexavalent chrome and reduced by contacting the contacting workpiece with a liquid or fine particle reducing agent.

Abstract: A method for electrode-based patterning of thin film, self-assembled nanoparticles. The method uses a variety of types of thin films and electrodes.

Abstract: The present invention pertains to a method for removing a substance (X) from a solid metal or semi-metal compound (M1X) by electrolysis in a melt of M2Y, which comprises conducting the electrolysis under conditions such that reaction of X rather than M2 deposition occurs at a electrode surface, and that X dissolves in the electrolyte M2Y. The substance X is either removed from the surface (i.e., M1X) or by means of diffusion extracted from the case material. The temperature of the fused salt is chosen below the melting temperature of the metal M1. The potential is chosen below the decomposition potential of the electrolyte.

Abstract: A method for stripping a fused thermal spray metal coating from the surface of a soft metallic substrate. The steps for the method include: immersing the coated metallic substrate in an aqueous solution of chromic acid, peroxide, and a second acid; immersing a metal cathode in the aqueous solution; applying a positive potential to the fused spray metal coated substrate and a negative potential to the metal cathode to generate a direct current between the substrate and the cathode; where the current is applied for a sufficient time to remove the coating. This method permits the electrochemical removal of fused and impermeable thermal spray metal coatings.

Abstract: A method of removing recast from a substrate is disclosed. The method includes chemically removing the recast using an etchant, which provides a visual indication of the presence of the recast when the part has been removed from the etchant. One example chemical etchant is comprised of a sulfuric acid solution that includes sodium chloride, sodium fluoride and ammonium persulfate. After chemical removal of the recast from the substrate, the recast is physically removed from the substrate, for example, by media blasting. The chemical and physical recast removal process can be repeated as desired. To ensure that all the recast has been removed, the substrate is wiped, for example, using a cloth. If all the recast has been removed, the cloth will not change in appearance or color.

Abstract: Apparatus and methods for removing coatings from metal components, such as metal components used in aircraft and other aerospace vehicles and the oil industry, as well as aqueous bath compositions. The metal component may be DC coupled with a counter electrode and immersed in an aqueous bath that includes an active oxygen source and a ligand in a composition effective to remove the coating. The aqueous bath may include hydrogen peroxide as the active oxygen source and may be maintained in a specific pH range if the temperature of the aqueous bath is controlled. In an alternative embodiment, the composition of the aqueous bath may include a non-peroxide active oxygen source, such as sodium perborate, and be maintained in a different specific pH range. An oxygen sensor may be provided to periodically monitor the concentration of active oxygen in the aqueous bath.

Abstract: A plating assembly for use in plating metallic materials onto a surface of a substrate is provided. The plating assembly comprising a delivery unit having a fluid chamber, a metallic source, and a porous insert. The plating assembly also comprising a receiving unit having a fluid chamber and a metallic receiver. The receiving unit also has a porous insert. The porous insert of the delivery unit being substantially aligned with, and spaced apart from, the porous insert of the receiving unit. The metallic receiver being substantially aligned with the porous insert of the delivery unit and a path being defined between the delivery unit and the receiving unit. Wherein a plating meniscus is capable of being defined in the path between the porous inserts of the delivery unit and the receiving unit and a substrate is capable of being moved through the plating meniscus to enable the plating of metallic materials onto the surface of the substrate. Examples for de-plating are also provided.

Abstract: A process for electrochemical stripping of components is disclosed. An operating point of the electrochemical stripping is determined under actual process conditions prior to the actual electrochemical stripping and is determined anew continuously, i.e., monitored and optionally adjusted during the electrochemical stripping.

Abstract: Method for removing coatings which have been applied to components such as turbine blades. After the end of the product life cycle of the turbine blades has been reached, these coatings can be removed to reuse the turbine blades after recoating. The coating, containing in particular chromium oxide compounds is removed via a stripping bath by adding alkanolamine compounds or salts containing such compounds as the inhibitor. These compounds advantageously prevent new chromium oxide compounds from being produced during the stripping of the turbine blades or the chromium oxide compounds present in the coating are removed effectively, so that the chromium oxide compounds cannot have an adverse influence on the removal rate of the stripping process. Advantageously reduced treatment times can thereby be achieved for the stripping process. By adding 2% triethanolamine, the treatment time in hydrochloric acid for example can be reduced to below one hour.

Abstract: A method for separating a metal-resin joint including the steps of: (1) immersing an article including a metal-resin joint with a counter electrode in an alkaline solution; and (2) applying a voltage over a certain time period between the metal portion of the joint and the counter electrode such that the potential of the metal portion is lower than that of a standard hydrogen electrode.

Abstract: A decontamination method for stripping radionuclides from the surface of stainless steel or aluminum material comprising the steps of contacting the metal with a moderately acidic carbonate/bicarbonate electrolyte solution containing sodium or potassium ions and thereafter electrolytically removing the radionuclides from the surface of the metal whereby radionuclides are caused to be stripped off of the material without corrosion or etching of the material surface.

Abstract: A method for electrochemically stripping components, especially gas turbine components, is provided. According to the method, the component from which a coating is to be removed is connected to a positive terminal of a voltage source or current source while an electrode is connected to a negative terminal thereof. An electrode is used that is precisely adapted to a region of the component to be stripped such that a gap between the region of the component to be stripped and the electrode is approximately constant over the entire region to be stripped.

Abstract: A highly accurate, efficient, and non-mechanical method of removing material from the surface of a golf club head using the principles of electrolysis. The process generally includes positioning at least one electrode in close proximity to a portion of a rear surface of a striking plate, flowing a liquid containing an electrolyte between the rear surface portion and the electrode, and applying a low voltage between the rear surface portion and the electrode. The electrode has an overall negative charge and the golf club head has an overall positive charge, such that a pulsed high-density DC current passes between the electrode and the rear surface portion. This results in negatively charged electrolytes in the liquid attracting positively charged molecules of the rear surface portion, such that the designated amount of material from the rear surface portion is removed by electro-chemical oxidation and carried away by the liquid flow.

Abstract: An apparatus for the superficial electrolytic treatment of metal strips, comprising several separate and non-communicating tanks, or containers, located along the path of metal strip (13). A series of electrodes in pairs (14?, 15?, 14?, 15?, 14??, 15??), arranged as tunnels, is situated along the path. Each pair is associated with a container (2?, 2?, 2??), in which an electrod 14?, 14?, 14??) of each pair is located above the strip and the other (15?, 15?, 15??) is located below said strip, in a reciprocally opposits position and at an appropriate distance. The electrode pairs alternately have opposite polarity and each of them is respectively associated with a container. Rollers (3, 3?, 3?, 3??) in pairs for strip pressing are situated at the common border of adjacent containes for the galvanic separation of the strip surface areas facing the electrode pairs of opposite polarity.

Abstract: An electrochemical process for selectively stripping at least one coating from the surface of a substrate is disclosed. The substrate (often a turbine engine component) is immersed in a composition through which electrical current flows. The composition includes a halide salt, such as sodium chloride, ammonium chloride, and potassium chloride. In preferred embodiments, the electrical current is direct current (DC). The process is especially useful for selectively removing portions of diffusion aluminide coatings. For example, the additive layer can efficiently be removed, without substantially affecting the underlying diffusion layer or substrate. Related stripping compositions and apparatuses are also described.

Abstract: An electrochemical process for simultaneously stripping diverse coatings from a metal substrate and, more particularly to the removal of MCrAlY and aluminide coatings from a base metal.

Abstract: A method for manufacturing a multiple walled tube comprising a rolling of a plated metal strip through at least two complete revolutions to form a tube having at least a double wall which has a plated layer on the inside of the tube, said rolling being followed by a heating of the tube to cause the surface of the tube walls, which are in contact with one another, to be brazed and wherein said metal strip is plated on one side, the other side being formed by the steel of the metal strip and wherein said brazing is realized by brazing directly the plated side on the steel.

Abstract: The present invention provides methods of polishing and/or cleaning copper interconnects using bis(perfluoroalkanesulfonyl) imide acids or copper tris(perfluoroalkanesulfonyl) methide acids compositions.

Abstract: The present invention provides methods of polishing and/or cleaning copper interconnects using sulfonic acid compositions.

Abstract: A system and process for cleaning a hollow interior or a passageway of a metal member including an external container having counter electrode material with a higher potential than the metal member with the counter electrode material being dc coupled to the metal member, and electrolyte passing through the container to contact the counter electrode material and fluidicly coupled into the hollow interior or the passageway of the metal member to clean same.

Abstract: A method of surface treatment of friction members includes providing a friction member made of PMMC material. A transfer layer is formed on the active surface of the friction member of removing the top layer of the matrix material to expose a surface with the embedded reinforcing particles.

Abstract: The present invention pertains to a method for removing a substance (X) from a solid metal or semi-metal compound (M1X) by electrolysis in a melt of M2Y, which comprises conducting the electrolysis under conditions such that reaction of X rather than M2 deposition occurs at a electrode surface, and that X dissolves in the electrolyte M2Y. The substance X is either removed from the surface (i.e., M1X) or by means of diffusion extracted from the case material. The temperature of the fused salt is chosen below the melting temperature of the metal M1. The potential is chosen below the decomposition potential of the electrolyte.

Abstract: An apparatus for the superficial electrolytic treatment of metal strips, comprising several separate and non-communicating tanks, or containers, located along the path of metal strip (13). A series of electrodes in pairs (14′, 15′, 14″, 15″, 14′″, 15′″), arranged as tunnels, is situated along the path. Each pair is associated with a container (2′, 2″, 2′″), in which an electrode (14, 14″, 14′″) of each pair is located above the strip and the other (15′, 15″, 15′″) is located below said strip, in a reciprocally opposite position and at an appropriate distance. The electrode pairs alternately have opposite polarity and each of them is respectively associated with a container.

Abstract: The present invention relates to a method for treating spent tin or tin/lead stripping solution used in the electronic industry, particularly in the manufacture of printed circuit boards or a lead frames. Said method comprises (i) electrolytically reducing copper ions in the solution to copper at a low temperature; (ii) electrolytically oxidizing Sn2+ and Pb2+ in the solution at a high temperature to form solid tin and lead oxides and hydroxides; (iii) separating solid tin and lead oxides and hydroxides from the solution; (iv) dissolving tin and lead oxides and hydroxides obtained in step (iii) in a strong alkali or acidic solution; and (v) electrolytically reducing the alkali or acidic solution obtained in step (iv) at a high temperature to recover metallic tin and lead. Also, the filtrate obtained in step (iii) above is useful for preparing fresh tin or tin/lead stripping solution.

Abstract: A sacrificial core (304) defining a cavity in a metallic or non-metallic shaped article of manufacture, e.g., a casting (302), is made from a metal that can be electrolytically dissolved. The sacrificial core (304) is removed from the article (302) by electrochemical machining. The sacrificial core (304) may be a hollow shell (306) incorporating an integral electrode (308) within the shell and electrically insulated from the shell.

Abstract: A system and process for chemical milling or stripping a surface portion and/or surface deposit from metal products, such as chemically milling a metal to remove surface defects and/or stripping non-metallic deposits from a metal surface. The metal product is associated with an electrolyte, such as by being immersed in a tank filled with the electrolyte, such as a diluted acid mixture. A counter electrode having a higher potential than the metal of the metal product is also associated with the electrolyte. The counter electrode is dc coupled to the metal product, or to a conductive component in direct contact with the metal product, such that electric current flows from the metal to the counter electrode due to the difference in the natural potentials of the metal and the counter electrode. The surface portion or deposit is thereby stripped or milled from the metal product.

Abstract: Methods and apparatuses for in-situ cleaning of semiconductor electroplating electrodes to remove plating metal without requiring the manual removal of the electrodes from the semiconductor plating equipment. The electrode is placed into the plating liquid and an electrical current having reverse polarity is passed between the electrode and plating liquid. Plating deposits which have accumulated on the electrode are electrochemically dissolved and removed from the electrode.

Abstract: The invention relates to a device for separating metal deposit from a mother plate used as a cathode in an electrolytic process, as metal electrorefining or metal electrowinning, in which device there is a supporting member for supporting the cathode to be treated, a member for releasing at least partly a metal deposit grown during the electrolytic process on a surface of the mother, and a member for support the released metal deposit. According to the invention the mother plate of a cathode (1, 21, 31, 41, 51) is provided with a growth affecting means (16, 24, 36, 43, 53) for creating an irregularity in the growth of the metal deposit (4) to be used as a hinged member when the metal deposit (4) is tilted to the mother plate of the cathode (1, 21, 31, 41, 51) in order to break the metal deposit (4) in two separate pieces along the irregularity in the growth.

Abstract: An electrochemical stripping method for selectively removing at least one coating from the surface of a substrate is described. The substrate is immersed in an aqueous composition through which electrical current flows. The composition includes an acid having the formula HxAF6, in which “A” is Si, Ge, Ti, Zr, Al, or Ga; and x is 1-6. Various coatings can be removed, such as diffusion or overlay coatings. The method can be used to fully-strip a coating (e.g., from a turbine component), or to partially strip one sublayer of the coating. Related processes and an apparatus are also described.

Abstract: Methods and apparatuses for in-situ cleaning of semiconductor electroplating electrodes to remove plating metal without requiring !the manual removal of the electrodes from the semiconductor plating equipment. The electrode is placed into the plating liquid and, an electrical current having reverse polarity is passed between the electrode and plating liquid. Plating deposits which have accumulated on the electrode are electrochemically dissolved and removed from the electrode.

Abstract: A process for recovery of valuable metals from superalloys by electrochemical decomposition is described, both electrodes being formed by the superalloy and the polarity of the electrolysis current being reversed with a frequency of from 0.005 to 5 Hz.

Abstract: An electrochemical stripping method for selectively removing at least one coating from the surface of a substrate is described. The substrate is immersed in an aqueous composition through which electrical current flows. The composition includes an acid having the formula HxAF6, in which “A” is Si, Ge, Ti, Zr, Al, or Ga; and x is 1-6. Various coatings can be removed, such as diffusion or overlay coatings. The method can be used to fully-strip a coating (e.g., from a turbine component), or to partially strip one sublayer of the coating. Related processes and an apparatus are also described.

Abstract: An aqueous solution (20) of an alkali hydroxide is stored and held in a tank (1). An electrode (5) is disposed in the tank (1), and a member (11) coated with a Ti-derived film is disposed in the tank (1) so as to be surrounded with the electrode (5). In this state, a power source (6) applies a negative potential to the electrode (5) and a positive potential to the member (11) to flow electricity between the electrode (5) and the member (11) immersed in the aqueous solution (20). Thus, the Ti-derived film coated on the surface of the member (11) is chemically removed by the aqueous solution (20).

Abstract: A process including: (a) creating an electrolytic cell composed of a metal surface as a first electrode, a second electrode, and an electrolytic solution, wherein the metal surface has a plurality of metal fibers connected to the metal surface; and (b) treating electrochemically the metal surface with externally supplied power to the electrolytic cell to sever a number of the metal fibers from the metal surface to result in severed metal fiber fragments unconnected with the metal surface.

Abstract: A process for creating surface microporosity on a titanium (or other metal) medical device includes creating a surface oxide layer on the device; placing the device, which is connected to a negative terminal of an electrical power supply, into a calcium chloride bath; connecting the positive terminal of the power supply to an anode immersed in or containing calcium chloride thereby forming an electrolytic cell; passing current through the cell; removing the device from the bath; and cooling and rinsing the device to remove any surface salt. If necessary, the device is etched to remove metal oxide which may have formed during the cooling process. The resulting device has a microporous surface structure. Alternatively, only a designated surface portion of a medical device is made microporous, either by applying a non-oxidizing mask, removing a portion of the oxide layer, or subtracting a portion of a microporous surface.

Abstract: A process for regeneration of electrolytes, in particular Na2SO4, from waste pickles created during picking of stainless steel, in particular stainless steel strips. The electrolytes are regenerated by adding NaxHySzOv in an acid solution whereby Cr6+ is reduced to Cr3+. Variables x, y, z and v having the following values: x=0 to 2, y=0 to 2, z=1 to 6, v=2 to 6.

Abstract: A process including: creating a galvanic cell composed of a substrate as an anode, a cathode, and an electrolytic solution, wherein the substrate includes a metal surface having a plurality of metal fibers connected to the metal surface, wherein the cathode is selected to be more noble than the metal surface resulting in the anode being the working electrode, wherein the galvanic cell spontaneously electrochemically treats the metal surface in the absence of power externally supplied to the galvanic cell; and allowing the spontaneous electrochemical treatment of the metal surface to continue for a time sufficient to sever a number of the metal fibers from the metal surface to result in severed metal fiber fragments unconnected with the metal surface.

Abstract: A novel photoresist stripping process is disclosed. Specifically, it has been found that if a printed wiring board panel having photoresist on its surface is used as a cathode during electrolysis in an alkaline solution, the result is a rapid and complete photoresist removal with minimal sheeting of removed photoresist and no evidence of chemical attack upon metallic traces on the printed wiring board.

Abstract: The present invention relates to a feedback controlled stripping system with integrated water management and acid recycling system. The system comprises a stripping tank containing an electrolyte bath stripping solution for removing a coating from at least one workpiece immersed in the stripping solution while a controlled absolute electrical potential is maintained on the at least one workpiece with respect to a reference electrode also immersed in the stripping solution, a rinse tank for rinsing the workpiece(s) after removal of the workpiece(s) from the stripping tank, and a distillation unit for receiving electrolyte containing dissolved metals from the stripping tank, for purifying the electrolyte received from the stripping tank, and for returning the purified electrolyte to the stripping tank. In a preferred embodiment, the stripping tank, the rinse tank, and the distillation unit are mounted to a skid. The system further includes a control module.

Abstract: A process for removing chloride ions from steel surfaces and measuring the amount present on the steel surface being tested employs a high frequency waveform alternating current treatment as a pre-measurement step to liberate the chloride ions into deionized water on the steel surface being tested. The conductivity of the water containing the chloride ions is measured in a conductivity cell mounted on the same steel surface being tested. Recovery of chloride ions originally present on the steel test surface (cathode) is 85-95% complete when a sine wave high frequency alternating current is used between the steel test surface (cathode) sealed below an insulating plastic box containing the deionized water and which plastic box contains a steel plate (anode) mounted within and immediately below the inside top of the plastic box conductivity cell. The conductivity of the water in the cell is measured by a conductivity meter after disconnecting the high frequency waveform alternating current.

Abstract: The present invention relates to a feedback controlled stripping system with integrated water management and acid recycling system. The system comprises a stripping tank containing an electrolyte bath stripping solution for removing a coating from at least one workpiece immersed in the stripping solution while a controlled absolute electrical potential is maintained on the at least one workpiece with respect to a reference electrode also immersed in the stripping solution, a rinse tank for rinsing the workpiece(s) after removal of the workpiece(s) from the stripping tank, and a distillation unit for receiving electrolyte containing dissolved metals from the stripping tank, for purifying the electrolyte received from the stripping tank, and for returning the purified electrolyte to the stripping tank. In a preferred embodiment, the stripping tank, the rinse tank, and the distillation unit are mounted to a skid. The system further includes a control module.

Abstract: The plant comprises: an electrolysis cell (1″) having a soluble anode (2″1) and an insoluble cathode (3″) without an interposed membrane, means for introducing the bath into the cell and for removing the bath from the cell, means for maintaining an appropriate bath density gradient in the said cell so that, if D1 is the density of the bath in the vicinity of the cathode and if D2 is the density of the bath in the vicinity of the anode, (D2−D1)>100 g/l. Associated process. By virtue of the densitometric separation, the dissolved metal is not redeposited on the cathode and the overall dissolution yield is improved.

Abstract: An electrochemical stripping process is described that strips at least one metallic coating from a substrate. Due to the electrochemical selectivity of the disclosed process, the parent alloy is minimally affected by the electrochemical stripping process. The process comprises providing an electrolyte; disposing the coated articles and at least one electrode in the electrolyte; applying a current between the electrode and the coated articles, and removing the at least one coating from the coated articles without modifying the parent alloy. The system for the electrochemical stripping process comprises an electrolyte; a direct current source; and plurality of electrodes from which a direct current may be directed to the article being stripped. The direct current source is capable of being connected to the coated articles and the plurality of electrodes. The system permits removal of the at least one coating from the parent alloy.