摘要:
An electrochemical machining system for metals and alloys having a strongly passivating character including an electrolyte solution that is free of hydrofluoric acid, an electrode in contact with the electrolyte solution, a workpiece spaced apart from the electrode and in contact with the electrolyte solution and a power source including a first electrical lead electrically coupled to the electrode and a second electrical lead electrically coupled to the workpiece, the power source being configured to pass an electric current between the electrode and the workpiece, wherein the electric current includes anodic pulses and cathodic pulses, and wherein the cathodic pulses are interposed between at least some of the anodic pulses.
摘要:
A method for electrochemically etching a metal layer through an etch-resist layer pattern using a non-active electrolyte solution is described. The method is particularly useful in fabrication of advanced fuel delivery systems for land-based power generation turbines and aerospace turbine engines; of components for advanced thermal management in aerospace electronic devices and in cooling channels; of stents used in medicine; and of microchannels for sensors, chemical reactors, and dialysis and the like. In one embodiment of the invention the metal layer is copper and the non-active electrolyte solution is a mixture of sodium nitrate and sodium chloride and a pulse electric current is employed to accomplish the electrochemical etching.
摘要:
A method and system for electrochemically machining a hollow body of a metal or a metal alloy. An electrode is positioned within a hollow body including a metal or metal alloy, where the hollow body has a variable internal diameter. The hollow body is oriented vertically, with the electrode oriented vertically therein. The hollow body is at least partially filled with an aqueous, acidic electrolyte solution, the electrolyte solution being devoid of hydrofluoric acid and having a viscosity less than 15 cP. An electric current is passed between the hollow body and the electrode, where the electric current includes a plurality of anodic pulses and a plurality of cathodic pulses, and where the cathodic pulses are interposed between at least some of the anodic pulses.
摘要:
An electrochemical finishing system for super conducting radio frequency (SCRF) cavities including a low viscosity electrolyte solution that is free of hydrofluoric acid, an electrode in contact with the electrolyte solution, the SCRF cavity being spaced apart from the electrode and in contact with the electrolyte solution and a power source including a first electrical lead electrically coupled to the electrode and a second electrical lead electrically coupled to the cavity, the power source being configured to pass an electric current between the electrode and the workpiece, wherein the electric current includes anodic pulses and cathodic pulses, and wherein the cathodic pulses are interposed between at least some of the anodic pulses. The SCRF cavity may be vertically oriented during the finishing process.
摘要:
An electrochemical finishing system for super conducting radio frequency (SCRF) cavities including a low viscosity electrolyte solution that is free of hydrofluoric acid, an electrode in contact with the electrolyte solution, the SCRF cavity being spaced apart from the electrode and in contact with the electrolyte solution and a power source including a first electrical lead electrically coupled to the electrode and a second electrical lead electrically coupled to the cavity, the power source being configured to pass an electric current between the electrode and the workpiece, wherein the electric current includes anodic pulses and cathodic pulses, and wherein the cathodic pulses are interposed between at least some of the anodic pulses. The SCRF cavity may be vertically oriented during the finishing process.
摘要:
A method and system for electrochemically machining a hollow body of a metal or a metal alloy. An electrode is positioned within a hollow body including a metal or metal alloy, where the hollow body has a variable internal diameter. The hollow body is oriented vertically, with the electrode oriented vertically therein. The hollow body is at least partially filled with an aqueous, acidic electrolyte solution, the electrolyte solution being devoid of hydrofluoric acid and having a viscosity less than 15 cP. An electric current is passed between the hollow body and the electrode, where the electric current includes a plurality of anodic pulses and a plurality of cathodic pulses, and where the cathodic pulses are interposed between at least some of the anodic pulses.
摘要:
A method and system for electrochemically machining a hollow body of a metal or a metal alloy. An electrode is positioned within a hollow body including a metal or metal alloy, where the hollow body has a variable internal diameter. The hollow body is oriented vertically, with the electrode oriented vertically therein. The hollow body is at least partially filled with an aqueous, acidic electrolyte solution, the electrolyte solution being devoid of hydrofluoric acid and having a viscosity less than 15 cP. An electric current is passed between the hollow body and the electrode, where the electric current includes a plurality of anodic pulses and a plurality of cathodic pulses, and where the cathodic pulses are interposed between at least some of the anodic pulses.
摘要:
A continuous layer of a metal is electrodeposited onto a substrate having both hydrodynamically inaccessible recesses and hydrodynamically accessible recesses on its surface by a two-step process in which the hydrodynamically inaccessible recesses are plated using a pulsed reversing current with cathodic pulses having a duty cycle of less than about 50% and anodic pulses having a duty cycle of greater than about 50% and the hydrodynamically accessible recesses are then plated using a pulsed reversing current with cathodic pulses having a duty cycle of greater than about 50% and anodic pulses having a duty cycle of less than about 50%.
摘要:
A continuous layer of a metal is electrodeposited onto a substrate having both hydrodynamically inaccessible recesses and hydrodynamically accessible recesses on its surface by a two-step process in which the hydrodynamically inaccessible recesses are plated using a pulsed reversing current with cathodic pulses having a duty cycle of less than about 50% and anodic pulses having a duty cycle of greater than about 50% and the hydrodynamically accessible recesses are then plated using a pulsed reversing current with cathodic pulses having a duty cycle of greater than about 50% and anodic pulses having a duty cycle of less than about 50%.
摘要:
A dewatering apparatus for cellulosic materials includes a chamber for an aqueous solution of a cellulosic material, an inner electrode in the chamber, an outer electrode in the chamber about the inner electrode, and a power supply connected to the inner electrode and the outer electrode applying a voltage potential across the electrodes to remove water associated with the aqueous solution and to dewater the cellulosic materials.