Racks for high-temperature metal processing

Abstract

In various embodiments, apparatuses for receiving and supporting one or more components during processing thereof at process temperatures greater than approximately 1000° C. feature refractory metal shelves separated by refractory metal support posts.

What is claimed is: 
     
         1 .- 35 . (canceled) 
     
     
         36 . An apparatus for receiving and supporting one or more components during processing thereof at a process temperature greater than approximately 1000° C., the apparatus comprising:
 a first shelf comprising a first refractory metal having a melting point greater than the process temperature; and 
 disposed beneath the first shelf, a base comprising (i) a plurality of spaced-apart cross bars each (a) defining a plurality of apertures therethrough and (b) comprising a second refractory metal having a melting point greater than the process temperature, and (ii) a plurality of spaced-apart through rods each (a) extending through the apertures of multiple ones of the cross bars and (b) comprising a third refractory metal having a melting point greater than the process temperature. 
 
     
     
         37 . The apparatus of  claim 36 , wherein the first shelf comprises one or more first lift hooks extending therefrom, the first shelf being separable from the base via a lifting force applied via the one or more first lift hooks. 
     
     
         38 . The apparatus of  claim 36 , wherein the base comprises one or more alignment features extending upward therefrom. 
     
     
         39 . The apparatus of  claim 36 , further comprising, disposed over the first shelf, a second shelf comprising a fourth refractory metal having a melting point greater than the process temperature. 
     
     
         40 . The apparatus of  claim 39 , further comprising:
 a first support tube (i) having an upper end and a lower end opposite the upper end, (ii) comprising a fifth refractory metal having a melting point greater than the process temperature, and (iii) configured to extend from the first shelf to the second shelf, wherein the upper end of the first support tube defines therein a plurality of notches; and   a support brace comprising a plurality of appendages for supporting the second shelf thereon, each appendage being configured for receipt into one of the notches of the upper end of the first support tube.   
     
     
         41 . The apparatus of  claim 40 , wherein:
 the first shelf defines a central aperture therethrough; and   the lower end of the first support tube is configured to extend through the central aperture of the first shelf.   
     
     
         42 . The apparatus of  claim 39 , further comprising:
 a plurality of first support posts, each first support post (i) comprising a fifth refractory metal having a melting point greater than the process temperature, (ii) configured to extend between the first shelf and the second shelf, and (iii) having an upper end and a lower end opposite the upper end,   wherein (i) the second shelf comprises one or more second lift hooks extending therefrom, and (ii) the second shelf and the first support posts are collectively separable, as a modular unit, from the first shelf via a lifting force applied via the one or more second lift hooks.   
     
     
         43 . The apparatus of  claim 42 , wherein the first shelf defines therein a plurality of apertures, the lower end of each first support post being configured to be received within one of the apertures. 
     
     
         44 . The apparatus of  claim 43 , wherein the lower end of each first support post is tapered. 
     
     
         45 . The apparatus of  claim 42 , wherein the upper end of each of the first support posts is threaded. 
     
     
         46 . The apparatus of  claim 42 , wherein:
 the second shelf defines a plurality of apertures defined therethrough; and   each of the first support posts defines a support collar proximate the upper end, a lateral dimension of the first support post above the support collar being smaller than a lateral dimension of the first support post below the support collar, whereby, when an upper end of a first support post is received in an aperture of the second shelf, a portion of the second shelf proximate the aperture rests upon the support collar of the first support post received in the aperture.   
     
     
         47 . The apparatus of  claim 42 , wherein
 the second shelf defines a plurality of apertures defined therethrough; and   the upper end of each of the first support posts is configured to protrude through one of the apertures.   
     
     
         48 . The apparatus of  claim 47 , further comprising a plurality of first nuts, each first nut (i) comprising a sixth refractory metal having a melting point greater than the process temperature, and (ii) being configured to engage with the upper end of one of the first support posts to thereby secure the one of the first support posts to the second shelf. 
     
     
         49 . The apparatus of  claim 48 , wherein each first nut defines therein a lower aperture, at least a portion of the lower aperture being threaded for engagement with the upper end of one of the first support posts. 
     
     
         50 . The apparatus of  claim 49 , wherein each first nut defines therein an upper aperture. 
     
     
         51 . The apparatus of  claim 50 , wherein at least a portion of the upper aperture is tapered. 
     
     
         52 . The apparatus of  claim 50 , further comprising:
 a third shelf comprising an seventh refractory metal having a melting point greater than the process temperature; and   a plurality of second support posts, each second support post (i) comprising a eighth refractory metal having a melting point greater than the process temperature, (ii) configured to extend between the second shelf and the third shelf, (iii) having an upper end, and (iv) having a lower end, opposite the upper end, for engagement with an upper aperture of one of the first nuts.   
     
     
         53 . The apparatus of  claim 36 , further comprising a shelf support disposed between the first shelf and the base, the shelf support comprising a fourth refractory metal having a melting point greater than the process temperature. 
     
     
         54 . A method of high-temperature brazing at a process temperature greater than approximately 1000° C., the method comprising:
 disposing within a furnace chamber an apparatus comprising:
 a first shelf comprising a first refractory metal having a melting point greater than the process temperature, and 
 disposed beneath the first shelf, a base comprising (i) a plurality of spaced-apart cross bars each (a) defining a plurality of apertures therethrough and (b) comprising a second refractory metal having a melting point greater than the process temperature, and (ii) a plurality of spaced-apart through rods each (a) extending through the apertures of multiple ones of the cross bars and (b) comprising a third refractory metal having a melting point greater than the process temperature; 
 
 disposing on the first shelf of the apparatus (i) a first component, (ii) a second component, and (iii) a brazing material disposed between the first and second components; 
 introducing within the furnace chamber a processing ambient; and 
 applying the process temperature within the furnace chamber, thereby melting the brazing material and joining the first and second components at a brazed joint therebetween. 
 
     
     
         55 . The method of  claim 54 , wherein introducing the processing ambient comprises at least partially evacuating the furnace chamber. 
     
     
         56 . The method of  claim 54 , wherein introducing the processing ambient comprises introducing a process gas within the furnace chamber. 
     
     
         57 . The method of  claim 56 , wherein the process gas comprises hydrogen.