Porous metallic structures

Abstract

In one aspect, there are provided methods for producing porous metallic structures, wherein the methods involve the use of collagen fibrils on the nanometer scale as a “sacrificial” scaffold upon which metal particles are deposited. Also disclosed are structures comprising a porous metallic matrix having favorable strength, porosity, and density characteristics. Structures produced in accordance with the present disclosure are useful for, inter alia, the fabrication of devices such as filters, heat exchangers, sound absorbers, electrochemical cathodes, fuel cells, catalyst supports, fluid treatment units, lightweight structures and biomaterials.

What is claimed: 
     
         1 . A porous metallic structure produced by
 blending a metal powder with a dispersion of milled collagen nanofibrils in a carrier to form a blend comprising a substantially homogeneous mixture of the metal powder, the collagen nanofibrils, and the carrier, wherein said collagen nanofibrils have an average diameter of about 10 nm to about 250 nm;   forming a shaped body from said blend;   heating said shaped body to a temperature above the eutectic point of the blend;   cooling said shaped body to a temperature below the eutectic point of the blend;   reducing the amount of carrier in said shaped body; and,   removing a major proportion of said collagen nanofibrils from the shaped body to form said porous metallic structure.   
     
     
         2 . A structure comprising a porous metallic matrix having
 a strength rating of about 50 to about 2000 grams;   an average pore size of about 0.1 to about 250 microns;   a density of about 1 g/mL to about 7 g/mL; and,   an average porosity of at least about 90%.   
     
     
         3 . The structure according to  claim 2 , wherein said structure is substantially spherical. 
     
     
         4 . The structure according to  claim 2  wherein said porous metallic matrix comprises one or more of aluminum, copper, stainless steel, nickel, tin, titanium, zinc, iron, chromium, and manganese. 
     
     
         5 . The structure according to  claim 4  wherein said porous metallic matrix comprises at least two of aluminum, copper, stainless steel, nickel, tin, titanium, and zinc. 
     
     
         6 . The structure according to  claim 5  wherein said porous metallic matrix comprises copper and at least one of aluminum, stainless steel, titanium, and zinc. 
     
     
         7 . The structure according to  claim 5  wherein said porous metallic matrix comprises a substantially homogenous distribution of a first metal and a second metal. 
     
     
         8 . The structure according to  claim 2  further comprising a substrate.