Coated articles and methods comprising a rhodium layer

Abstract

Coated articles and methods for applying coatings including a rhodium layer are described. In some cases, the coating can exhibit desirable properties and characteristics such as durability, corrosion resistance, and high conductivity. The articles may be coated, for example, using an electrodeposition process.

1 . An article comprising:
 a base material;   a barrier layer formed on the base material;   a metal layer formed on the barrier layer; and   a Rh layer formed on the metal layer and having a thickness between about 1 microinch and about 5 microinches.   
     
     
         2 . The article of  claim 1 , wherein the barrier layer comprises silver. 
     
     
         3 . The article of  claim 2 , wherein the barrier layer comprises a silver-based alloy. 
     
     
         4 . The article of  claim 1 , wherein the barrier layer comprises nickel. 
     
     
         5 . The article of  claim 4 , wherein the barrier layer comprises a nickel-based alloy. 
     
     
         6 . The article of  claim 5 , wherein the nickel-based alloy further comprises tungsten and/or molybdenum. 
     
     
         7 . The article of  claim 5 , wherein the nickel-based alloy further comprises phosphorous. 
     
     
         8 . The article of  claim 5 , wherein the nickel-based alloy further comprises cobalt. 
     
     
         9 . The article of  claim 5 , wherein the nickel-based alloy further comprises palladium. 
     
     
         10 . The article of  claim 1 , wherein the barrier layer comprises palladium. 
     
     
         11 . The article of  claim 1 , wherein the barrier layer has a nanocrystalline grain size. 
     
     
         12 . The article of  claim 1 , wherein the metal layer has a nanocrystalline grain size. 
     
     
         13 . The article of  claim 1 , wherein the metal layer comprises a metal selected from the group consisting of Au, Ru, Os, Rh, Ir, Pd, Pt, and Ag. 
     
     
         14 . The article of  claim 1 , wherein the metal layer comprises a silver-based alloy. 
     
     
         15 . The article of  claim 1 , wherein the metal layer comprises a silver-based alloy and the barrier layer comprises a nickel-based alloy. 
     
     
         16 . The article of  claim 1 , wherein the metal layer comprises a silver-based alloy further comprising molybdenum and/or tungsten and the barrier layer comprises a nickel-based alloy further comprising molybdenum and/or tungsten. 
     
     
         17 . The article of  claim 1 , wherein the metal layer comprises a silver-tungsten alloy and the barrier layer comprises a nickel-tungsten alloy. 
     
     
         18 . The article of  claim 1 , wherein the Rh layer is formed directly on the metal layer. 
     
     
         19 . The article of  claim 1 , wherein the Rh layer is electrodeposited. 
     
     
         20 . The article of  claim 1 , wherein the Rh layer has a nanocrystalline grain size. 
     
     
         21 . The article of  claim 1 , wherein the base material comprises a conductive metal. 
     
     
         22 . A method comprising
 electrodepositing a barrier layer on a base material;   electrodepositing a metal layer on the barrier layer; and   electrodepositing a Rh layer on the metal layer, wherein the Rh layer has a thickness between about 1 microinch and about 5 microinches.   
     
     
         23 - 42 . (canceled)