Controllably-Formed Brazing Structures And Related Compositions And Methods

Abstract

The present disclosure provides compositions and methods for forming three-dimensional structures atop substrates. These structures may be formed and processed so as to braze together two substrates. The structures may be controllably formed in three dimensions so as to accommodate virtually any substrate geometry or configuration. The structures may also be disposed so as to maintain spacing between two surfaces.

What is claimed: 
     
         1 . A method, comprising:
 dispensing, at a location on a first substrate, an amount of a flowable particulate composition comprising an aerogel and a binder material,   the amount of the flowable particulate material maintaining a spacing between the first substrate and a second substrate.   
     
     
         2 . The method of  claim 1 , further comprising solidifying at least part of the amount of flowable particulate material. 
     
     
         3 . The method of  claim 2 , wherein the at least solidifying is effected by heating. 
     
     
         4 . The method of  claim 3 , wherein the heating is effected by a laser. 
     
     
         5 . The method of  claim 1 , further comprising effecting a reduced pressure in a region between the first and second substrates, the region comprising the spacing. 
     
     
         6 . The method of  claim 5 , wherein the effecting a reduced pressure in the region comprises sealably vacuum brazing together the first and second substrates so as to give rise to the reduced pressure in the region. 
     
     
         7 . The method of  claim 1 , further comprising bending the first and second substrates under such conditions that the amount of flowable particulate material maintains the spacing between the first and second substrates. 
     
     
         8 . The method of  claim 2 , wherein the flowable composition further comprises a brazing material 
     
     
         9 . The method of  claim 8 , further comprising curing the binder material so as to suspend the brazing material in the cured binder material. 
     
     
         10 . The method of  claim 9 , further comprising brazing the brazing material. 
     
     
         11 . The method of  claim 10 , wherein curing the binder material is effected at a first level of energy exposure, and wherein brazing the brazing material is effected at a second level of energy exposure that is greater than the first level of energy exposure. 
     
     
         12 . The method of  claim 1 , wherein the first and second substrates are tubes arranged in a concentric manner. 
     
     
         13 . The method of  claim 12 , further comprising bending the first and second tubes. 
     
     
         14 . The method of  claim 2 , wherein the solidifying is effected contemporaneously with the dispensing. 
     
     
         15 . The method of  claim 2 , further comprising at least partially eliminating the structure. 
     
     
         16 . The method of  claim 15 , wherein the at least partially eliminating is effected by heating. 
     
     
         17 . An article, comprising:
 a first substrate and a second substrate,   the first and second substrates being spaced apart from one another by a sealed volume between the first and second substrates,   the sealed volume defining within a reduced pressure, and   wherein each of the first substrate, the second substrate, and the sealed volume comprises a first bend that is complementary to a first bend in the other of the first substrate, the second substrate, and the sealed volume.   
     
     
         18 . The article of  claim 17 , wherein the first and second substrates are tubular in configuration. 
     
     
         19 . The article of  claim 17 , the sealed volume having within it one or more byproducts of the thermal decomposition of a composition that comprises one or both of a binder and an aerogel. 
     
     
         20 . The article of  claim 17 , wherein each of the first substrate, the second substrate, and the sealed volume comprises a second bend that is complementary to the second bend of the others of the first substrates, the second substrate, and the sealed volume.