Methods for producing corrosion resistant electrodeposited nickel coatings

Abstract

Embodiments of the present methods deposit smooth, semi-bright nickel coatings from a nickel bath at room temperature, with relatively high concentrations (between about 5 and about 10%) of an organic modifier (such as butanol) under acidic conditions and using a modified pulse potential. The methods for electrodepositing nickel coatings result in nickel coatings that have improved internal structure and corrosion resistance.

What is claimed is: 
     
         1 . A method for electrodepositing nickel coatings, comprising:
 preparing an aqueous bath comprising nickel and about 5% to about 10% by volume of an organic modifier, wherein the aqueous bath has an acidic pH;   submerging electrode substrates in the aqueous bath; and   using modified pulse reverse deposition to electrodeposit the nickel coatings on the substrates.   
     
     
         2 . The method of  claim 1 , wherein the organic modifier is butanol. 
     
     
         3 . The method of  claim 1 , wherein the acidic pH is about 2.5 to about 3.5. 
     
     
         4 . The method of  claim 1 , wherein the aqueous bath further comprises sodium borate. 
     
     
         5 . The method of  claim 1 , wherein all steps are carried out at room temperature. 
     
     
         6 . An electrodeposited nickel coating prepared by the method of  claim 1 . 
     
     
         7 . A method for electrodepositing nickel coatings, comprising:
 preparing an aqueous bath comprising nickel, sodium borate, and about 5% to about 10% by volume of butanol, wherein the aqueous bath has pH of about 2.5 to about 3.5;   submerging electrode substrates in the aqueous bath; and   using modified pulse reverse deposition to electrodeposit the nickel coatings on the substrates, wherein all steps are carried out at room temperature.   
     
     
         8 . An electrodeposited nickel coating prepared by the method of  claim 7 .