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 .- 50 . (canceled) 
     
     
         51 . 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 planar first shelf (i) comprising a first refractory metal having a melting point greater than the process temperature and (ii) defining therein a plurality of apertures; 
 a plurality of first support posts, each first support post (i) comprising a second refractory metal having a melting point greater than the process temperature, and (ii) having a lower end for engagement with an aperture of the first shelf; and 
 a planar second shelf (i) comprising a third refractory metal having a melting point greater than the process temperature and (ii) defining therein a plurality of apertures, each aperture of the second shelf being configured to receive an upper end of one of the first support posts, 
 wherein the upper end of each first support post defines therethrough a dowel pin mount, whereby, when the upper end of each first support post is received in an aperture of the second shelf, the dowel pin mount of each first support post is disposed above a top surface of the second shelf. 
 
     
     
         52 . The apparatus of  claim 51 , wherein the upper end of each of the first support posts defines a support collar below the dowel pin mount, 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 such that a portion of the second shelf proximate each aperture thereof rests upon the support collar of the first support post received in the aperture. 
     
     
         53 . The apparatus of  claim 52 , wherein a portion of each first support post above the support collar thereof is unthreaded. 
     
     
         54 . The apparatus of  claim 51 , wherein (i) each of the apertures defined in the first shelf is threaded through at least a portion of its thickness, and (ii) the lower end of each of the first support posts is threaded. 
     
     
         55 . The apparatus of  claim 51 , wherein at least one of the first, second, or third refractory metals comprises a TZM alloy. 
     
     
         56 . The apparatus of  claim 51 , wherein at least one of the first, second, or third refractory metals comprises at least one of Nb, Ta, Re, W, or Mo. 
     
     
         57 . The apparatus of  claim 51 , wherein the dowel pin mount of each first support post extends through, and is substantially perpendicular to, a central axis thereof. 
     
     
         58 . The apparatus of  claim 51 , further comprising a plurality of locking pins, each locking pin (i) comprising a fourth refractory metal having a melting point greater than the process temperature and (ii) being receivable within a dowel pin mount of a first support post, thereby preventing disengagement of the first support posts from the second shelf. 
     
     
         59 . The apparatus of  claim 58 , wherein each locking pin defines one or more apertures therethrough, each aperture extending substantially perpendicular to an axial length of the locking pin. 
     
     
         60 . The apparatus of  claim 59 , further comprising a plurality of retaining wires, each retaining wire (i) comprising a fifth refractory metal having a melting point greater than the process temperature and (ii) being receivable within an aperture of a locking pin, thereby preventing disengagement of the locking pin from the first support post in which it is received. 
     
     
         61 . The apparatus of  claim 58 , wherein each locking pin defines two or more apertures therethrough. 
     
     
         62 . The apparatus of  claim 61 , further comprising a plurality of retaining wires, each retaining wire (i) comprising a fifth refractory metal having a melting point greater than the process temperature and (ii) being receivable within an aperture of a locking pin, thereby preventing disengagement of the locking pin from the first support post in which it is received. 
     
     
         63 . The apparatus of  claim 51 , further comprising one or more additional shelves disposed vertically below the first shelf. 
     
     
         64 . The apparatus of  claim 51 , further comprising, disposed below the first shelf, a shelf support comprising a plurality of interconnected cross braces, each cross brace comprising a sixth refractory metal having a melting point greater than the process temperature. 
     
     
         65 . The apparatus of  claim 64 , wherein the first shelf defines a central aperture therethrough, the apparatus further comprising a support tube (i) having a lower end for extending through the central aperture of the first shelf and defining a plurality of notches, each notch configured to receive therein one of the cross braces of the shelf support, and (ii) comprising a seventh refractory metal having a melting point greater than the process temperature. 
     
     
         66 . The apparatus of  claim 65 , wherein the support tube has an upper end opposite the lower end, the upper end defining therein a plurality of notches, the apparatus further comprising 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 support tube. 
     
     
         67 . The apparatus of  claim 64 , further comprising, disposed beneath the shelf support, a base comprising (i) a plurality of spaced-apart cross bars each defining a plurality of apertures therethrough, and (ii) a plurality of spaced-apart through rods each extending through the apertures of multiple ones of the cross bars. 
     
     
         68 . The apparatus of  claim 67 , wherein:
 the base comprises one or more alignment features extending upward therefrom; and   the shelf support comprises one or more brackets each for receiving one of the one or more alignment features.   
     
     
         69 . The apparatus of  claim 51 , further comprising, 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 fourth 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 fifth refractory metal having a melting point greater than the process temperature. 
     
     
         70 . The apparatus of  claim 51 , wherein the lower end of each of the first support posts defines a support shoulder therein, a lateral dimension of each first support post above the support shoulder being larger than a lateral dimension of the lower end thereof. 
     
     
         71 . 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 planar first shelf (i) comprising a first refractory metal having a melting point greater than the process temperature and (ii) defining therein a plurality of apertures, 
 a plurality of first support posts, each first support post (i) comprising a second refractory metal having a melting point greater than the process temperature, and (ii) having a lower end for engagement with an aperture of the first shelf, and 
 a planar second shelf (i) comprising a third refractory metal having a melting point greater than the process temperature and (ii) defining therein a plurality of apertures, each aperture of the second shelf being configured to receive an upper end of one of the first support posts, 
 wherein the upper end of each first support post defines therethrough a dowel pin mount, whereby, when the upper end of each first support post is received in an aperture of the second shelf, the dowel pin mount of each first support post is disposed above a top surface of the second shelf; 
 
 disposing on the first shelf or the second 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.