Method and Apparatus for Continuously Applying Nanolaminate Metal Coatings

Abstract

Described herein are apparatus and methods for the continuous application of nanolaminated materials by electrodeposition.

1 . An apparatus for electrodepositing a nanolaminate coating comprising:
 at least a first electrodeposition cell through which a conductive workpiece is moved at a rate,   a rate control mechanism that controls the rate the workpiece is moved through the electrodeposition cell;   an optional mixer for agitating an electrolyte during the electrodeposition process;   an optional flow control unit for applying the electrolyte to the workpiece;   an electrode; and   a power supply controlling the current density applied to the workpiece in a time varying manner as it moves through the cell.   
     
     
         2 . The apparatus of  claim 1 , wherein controlling the current density in a time varying manner comprises applying two or more different current densities to the workpiece as it moves through the electrodeposition cell. 
     
     
         3 . The apparatus of  claim 2 , wherein controlling the current density in a time varying manner comprises applying an offset current, so that the workpiece remains cathodic when it is moved through the electrodeposition cell and the electrode remains anodic. 
     
     
         4 . The apparatus of  claim 1 , wherein the time varying manner comprises one or more of: varying the baseline current, pulse current modulation and reverse pulse current modulation. 
     
     
         5 .- 7 . (canceled) 
     
     
         8 . The apparatus of  claim 1 , further comprising a first location, from which the workpiece is moved to the electrodeposition cell, and/or a second location, for receiving the workpiece after it has moved through the electrodeposition cell, wherein the first and/or second location comprises a spool or a spindle, and wherein the workpiece is a wire, rod, sheet or tube that can be wound on said spool or around said spindle. 
     
     
         9 .- 13 . (canceled) 
     
     
         14 . The apparatus of  claim 1 , further comprising one or more locations between the first location and the electrodeposition cell, where the workpiece is contacted with one or more of: a solvent, an acid, a base, an etchant, and a rinsing agent to remove said solvent, acid, base, or etchant. 
     
     
         15 . (canceled) 
     
     
         16 . A method of electrodepositing a nanolaminate coating comprising:
 moving a workpiece through an apparatus comprising at least a first electrodeposition cell at a rate, where the electrodeposition cell comprises an electrode and an electrolyte comprising salts of two or more different electrodepositable metals; and   controlling the mixing rate and/or the current density applied to the workpiece in a time varying manner as it moves through the cell, thereby electrodepositing a nanolaminate coating.   
     
     
         17 . The method of  claim 16 , wherein controlling the current density in a time varying manner comprises applying two or more different current densities to the workpiece by varying one or more of the baseline current, pulse current modulation and reverse pulse current modulation as the workpiece moves through the electrodeposition cell, wherein the workpiece is a wire, rod, sheet or tube. 
     
     
         18 . The method of  claim 17 , wherein controlling the current density in a time varying manner comprises applying an offset current, so that the workpiece remains cathodic when it is moved through the electrodeposition cell and the electrode remains anodic. 
     
     
         19 . (canceled) 
     
     
         20 . The method of  claim 16 , wherein each electrodeposition cell further comprises a mixer and/or an ultrasonic agitator, and the method further comprises agitating the electrolyte with the mixer and/or agitator continuously or in a non-continuous fashion to control the mixing rate at a single rate or at varying rates. 
     
     
         21 .- 22 . (canceled) 
     
     
         23 . The method of  claim 16 , wherein the apparatus further comprises a first location, from which the workpiece is moved to the electrodeposition cell, and/or a second location, for receiving the workpiece after it has moved through the electrodeposition cell, the method further comprising moving the workpiece from the first location to the electrodeposition cell and/or moving the workpiece from the electrodeposition cell to the second location, wherein the rate the workpiece is moved through the electrodeposition cell is controlled. 
     
     
         24 . The method of  claim 23 , wherein the apparatus further comprises:
 (i) one or more locations between the first location and the electrodeposition cell, and the method further comprises contacting the workpiece with one or more of: a solvent, an acid, a base, and an etchant, and rinsing to remove said solvent, acid, base, and etchant; and/or   (ii) one or more locations between the electrodeposition cell and said second location, and the method further comprises contacting the workpiece with one or more of: a solvent, an acid, a base, a passivation agent, and a rinsing agent to remove the solvent, acid base, and passivation agent.   
     
     
         25 .- 29 . (canceled) 
     
     
         30 . The method of  claim 17 , wherein electrodepositing a nanolaminate coating comprises: the electrodeposition of a layered composition, individual layers comprising one or more different elements independently selected from Ag, Al, Au, Be, Co, Cr, Cu, Fe, Hg, In, Mg, Mn, Mo, Nb, Nd, Ni, Pd, Pt, Re, Rh, Sb, Sn, Pb, Ta, Ti, W, V, Zn and Zr, wherein each of said elements is present at greater than 0.001% by weight; or the electrodeposition of an alloy comprising two or more different metals selected from the group consisting of: Zn and Fe, Zn and Ni, Co and Ni, Ni and Fe, Ni and Cr, Ni and Al, Cu and Zn, Cu and Sn or a composition comprising Al, Ni and Co. 
     
     
         31 .- 32 . (canceled) 
     
     
         33 . The method according to  claim 17 , wherein the nanolaminate coating comprises at least one portion consisting of a plurality of layers, wherein each of said layers has a thickness in a range from about 5 nm to about 250 nm, and wherein the nanolaminate coating comprises a plurality of first layers and second layers that differ in structure or composition, and which may have discrete or diffuse interfaces between the first and second layers. 
     
     
         34 .- 38 . (canceled) 
     
     
         39 . The method of  claim 33 , wherein each said first layer comprises nickel in a range independently selected from 1%-5%, 5%-7%, 7%-10%, 10%-15%, 15%-20%, 20%-30%, 30%-40%, 40%-50%, 50%-55%, 55%-60%, 60%-65%, 65%-70%, 70%-75%, 75%-80%, 80%-85%, 85%-90%, 90%-92%, 92%-93%, 93%-94%, 94%-95%, 95%-96%, 96%-97%, 97%-98% or 98%-99%, and the balance of the layer is cobalt and/or chromium. 
     
     
         40 . The method of  claim 33 , wherein each second layer comprises cobalt and/or chromium or each second layer comprises iron in the range from 1% to 35% and the balance of the layer is nickel. 
     
     
         41 . The method of  claim 33 , wherein each said first layer comprises nickel or zinc in a range independently selected from 1%-5%, 5%-7%, 7%-10%, 10%-15%, 15%-20%, 20%-30%, 30%-40%, 40%-50%, 50%-55%, 55%-60%, 60%-65%, 65%-70%, 70%-75%, 75%-80%, 80%-85%, 85%-90%, 90%-92%, 92%-93%, 93%-94%, 94%-95%, 95%-96%, 96%-97%, 97%-98% or 98%-99%, and the balance of the layer comprises iron. 
     
     
         42 .- 46 . (canceled)