Delayed cure additive manufacturing

Abstract

A method for manufacturing a part includes fabricating an object in an additive fabrication stage, the object including a solid mold forming a cavity in the shape of a part with uncured or incompletely cured build material disposed therein. The build material in the cavity is cured in a curing stage that occurs at least partially after the additive fabrication stage. The build material undergoes a phase change mechanism occurring during the additive fabrication stage and a distinct polymerization mechanism occurring during the curing stage and at least partly after the additive fabrication stage of the object and cures the build material by a polymerization process.

1 . A method comprising:
 fabricating a three-dimensional structure including a plurality of materials, the fabricating including:
 emitting a first phase change material of the plurality of phase change materials at a first printing temperature above a first phase change temperature of the first phase change material, wherein the first phase change material cools to a first stable temperature below the first phase change temperature after the emitting, and 
 emitting a second phase change material of the plurality of phase change materials at a second printing temperature above a second phase change temperature of the second phase change material, the second phase change material being curable by a chemical reaction at a curing temperature greater than the second printing temperature, wherein the second phase change material cools to a second stable temperature below the second phase change temperature after the emitting; 
 wherein, upon completion of fabrication of the three-dimensional structure, the first phase change material encases the second phase change material in an uncured state. 
   
     
     
         2 . The method of  claim 1  further comprising initiating curing of the second phase change material after the completing of the fabricating including causing the second phase change material to heat to the curing temperature. 
     
     
         3 . The method of  claim 2  wherein initiating curing of the second phase change material includes heating the second phase change material to an initiation temperature greater than or equal to the second phase change temperature. 
     
     
         4 . The method of  claim 3  wherein the initiation temperature is less than the curing temperature. 
     
     
         5 . The method of  claim 3  wherein the heating of the second phase change material causes a polymerization initiation catalyst suspended in the second phase change material to interact with a monomer suspended in the second phase change material. 
     
     
         6 . The method of  claim 5  wherein the interaction of the polymerization initiation catalyst and the monomer is caused by the second phase change material flowing. 
     
     
         7 . The method of  claim 3  wherein the initiation temperature is greater than or equal to the curing temperature. 
     
     
         8 . The method of  claim 2  wherein causing the second phase change material to heat to the curing temperature includes exposing the second phase change material to ultraviolet (UV) radiation. 
     
     
         9 . The method of  claim 1  wherein the curing temperature is less than the first phase change temperature. 
     
     
         10 . The method of  claim 1  further comprising causing the second phase change material to cure, wherein the cured second phase change material is stable at the first phase change temperature. 
     
     
         11 . The method of  claim 10  further comprising removing the first phase change material from the three-dimensional structure by heating the first phase change material to the first phase change temperature. 
     
     
         12 . The method of  claim 1  wherein fabricating the three-dimensional structure includes forming a solidified three-dimensional support structure from the first phase change material where the solidified three-dimensional support structure defines cavity with a three-dimensional shape containing the second phase change material, the forming including:
 incrementally adding parts of the combination including depositing parts with both the first phase change material and the second phase change material, the depositing including,
 depositing the first phase change material in liquid form, 
 causing solidification of the deposited first phase change material to form a part of the solidified support structure, and 
 depositing the second phase change material contained by the support structure. 
 
 
     
     
         13 . The method of  1  wherein the first phase change material comprises a wax. 
     
     
         14 . The method of  claim 12  wherein incrementally adding parts of the combination includes depositing a plurality of layers of material. 
     
     
         15 . The method of  claim 14  wherein at least some layers of material of the plurality of layers of material are deposited using a jetting process.