Article exhibiting improved resistance to galvanic corrosion

Abstract

An article having a first member formed from a first metal and a second member connected with the first member at a contact area. The second member is formed from a second metal having high reduction reaction kinetics and galvanic corrosion driving force relative the first member, wherein the second metal is more noble than the first metal. A material for substantially eliminating the galvanic corrosion problem by reducing the reduction reaction kinetics of the second metal in the presence of an electrolyte is provided between the first and second metals. In a preferred embodiment, the article is a heat exchanger wherein the first member is a fin collar and the second member a tube and the material for reducing is a coating on the tube has low reduction reaction kinetics relative to copper for reducing corrosion activities between the tube and fin collar.

What is claimed is:  
     
         1 . A heat exchanger, comprising: 
 a fin collar formed from aluminum;    a tube connected with said fin collar at a contact area, said tube formed from copper having a surface and having high reduction reaction kinetics relative said aluminum, wherein said copper is more noble than said aluminum; and    a tin alloy coating on said copper of said tube having means for reducing the reduction reaction kinetics of said copper for reducing corrosion activities of the aluminum of said fin collar relative to the copper of the tubes in the presence of an electrolyte.