Mold releasable pattern material for use in investment casting

Abstract

A composition for use in investment casting includes a pattern material. The pattern material has internal mold releasability. The composition is suitable for use in investment casting. The pattern material may include a wax, a resin, a filler, and/or a fluorochemical. The pattern material may be capable of being injected numerous consecutive times without requiring the application of an external mold release agent (such as spraying silicone release agent) to a die used in the investment casting process. The pattern material would preferably have sufficient mold releasability to not adhere to the die, but sufficient adhesion to adhere to a shell-forming material, such as a ceramic slurry.

1 . A wax-based pattern material for use in investment casting, comprising: 
 a wax; and    a fluorochemical;    wherein the pattern material is suitable for use in investment casting.    
   
   
       2 . The pattern material of  claim 1 , further comprising a filler.  
   
   
       3 . The pattern material of  claim 2 , wherein the filler comprises at least two different types of filler.  
   
   
       4 . The pattern material of  claim 1 , further comprising a resin.  
   
   
       5 . The pattern material of  claim 4 , further comprising a filler.  
   
   
       6 . The pattern material of  claim 1 , further comprising an ash content of less than about 0.02%.  
   
   
       7 . The pattern material of  claim 1 , further comprising a shrinkage of no more than about 0.01 inch per inch.  
   
   
       8 . A wax-based pattern material for use in investment casting, comprising: 
 about 15 wt. % to about 50 wt. % wax;    about 10 wt. % to about 60 wt. % resins; and    a fluorochemical, fluorochemicals comprising less than about 5 wt. %.    
   
   
       9 . The pattern material of  claim 8 , further comprising an ash content of less than about 0.02%.  
   
   
       10 . The pattern material of  claim 8 , further comprising about 10 wt. % to about 50 wt. % filler.  
   
   
       11 . The pattern material of  claim 8 , comprising about 20 wt. % to about 50 wt. % resins.  
   
   
       12 . The pattern material of  claim 8 , comprising less than about 1 wt. % fluorochemicals.  
   
   
       13 . A composition for use in investment casting, comprising: 
 a pattern material, the pattern material comprising internal mold releasability; and    wherein the composition is suitable for use in investment casting.    
   
   
       14 . The composition of  claim 13 , wherein the pattern material comprises a wax, an additive that contributes to the internal mold releasability, and a resin.  
   
   
       15 . The composition of  claim 13 , wherein the pattern material is configured to have sufficient internal mold releasability such that a die can use the pattern material at least about 20 times without requiring application of an external mold release agent.  
   
   
       16 . The composition of  claim 15 , wherein the pattern material is configured to have sufficient internal mold releasability such that a die comprising a deep draw can use the pattern material at least about 20 times without requiring application of an external mold release agent.  
   
   
       17 . The composition of  claim 15 , wherein the pattern material comprises sufficient adhesion to a ceramic slurry to form a shell.  
   
   
       18 . The composition of  claim 13 , wherein the pattern material comprises an additive that contributes to the internal mold releasability, the additive selected such that the additive has a higher concentration on surfaces of a pattern molded using the composition than in an interior of the pattern.  
   
   
       19 . The composition of  claim 13 , further comprising a fluorochemical which contributes to the internal mold releasability of the pattern material.  
   
   
       20 . The composition of  claim 13 , wherein the pattern material comprises a shrinkage of no more than about 0.01 inch per inch.  
   
   
       21 . The composition of  claim 13 , further comprising an ash content of less than about 0.02%.  
   
   
       22 . The composition of  claim 13 , wherein the composition is solid at room temperature.  
   
   
       23 . The composition of  claim 13 , wherein the composition comprises an additive that contributes to the internal mold releasability of the pattern material, wherein the additive contributes to the internal mold releasability of the pattern material such that the pattern material with the additive may be used to make at least about three times as many consecutive quality parts as the same pattern material without the additive.  
   
   
       24 . A method of investment casting, comprising: 
 forming a pattern using a pattern material, the pattern material comprising internal mold releasability;    forming a shell using the pattern;    removing the pattern material from the shell; and    casting a product using the shell.    
   
   
       25 . The method of  claim 24 , wherein the pattern material comprises a wax and a resin.  
   
   
       26 . The method of  claim 24 , wherein the pattern material comprises a fluorochemical.  
   
   
       27 . The method of  claim 24 , further comprising recovering the pattern material removed from the shell.  
   
   
       28 . The method of  claim 24 , wherein the pattern material is solid at room temperature.  
   
   
       29 . The method of  claim 24 , wherein forming a pattern using a pattern material does not comprise applying an external mold release agent to a die used to form the pattern.  
   
   
       30 . The method of  claim 24 , wherein the pattern material is configured to have sufficient internal mold releasability such that a die can use the pattern material at least about 40 times without requiring application of an external mold release agent.  
   
   
       31 . A method of investment casting, comprising: 
 forming a pattern using a pattern material, forming a pattern using a pattern material not comprising applying an external mold release agent to a die used to form the pattern more than once every 100 shots;    forming a shell using the pattern;    removing the pattern material from the shell; and    casting a product using the shell.    
   
   
       32 . The method of  claim 31 , wherein the pattern material comprises a wax and a resin.  
   
   
       33 . The method of  claim 32 , wherein the pattern material further comprises a filler.  
   
   
       34 . The method of  claim 32 , wherein the pattern material comprises a fluorochemical.  
   
   
       35 . The method of  claim 31 , further comprising recovering the pattern material removed from the shell.  
   
   
       36 . The method of  claim 31 , wherein the pattern material is solid at room temperature.  
   
   
       37 . The method of  claim 31 , wherein forming a pattern using a pattern material does not comprise applying an external mold release agent to a die used to form the pattern.  
   
   
       38 . A method of investment casting, comprising: 
 forming a pattern using a pattern material,    forming a shell using the pattern;    removing the pattern material from the shell; and    casting a product using the shell;    wherein substantially no flow or open knit lines are formed in the pattern.    
   
   
       39 . The method of  claim 38 , wherein a die is used to form the pattern and the die comprises at least one pin around which the pattern material must flow.  
   
   
       40 . The method of  claim 38 , wherein the product cast using the shell comprises a complicated part.  
   
   
       41 . The method of  claim 38 , wherein forming a pattern using a pattern material not comprising applying an external mold release agent to a die used to form the pattern more than once every 100 shots.  
   
   
       42 . The method of  claim 38 , wherein the pattern material comprises internal mold releasability.  
   
   
       43 . The method of  claim 38 , wherein the pattern material comprises a wax and a resin.  
   
   
       44 . The method of  claim 38 , wherein the pattern material comprises a fluorochemical.  
   
   
       45 . The method of  claim 38 , wherein the pattern material comprises an additive that contributes to internal mold releasability of the pattern material, the additive selected such that the additive has a higher concentration on surfaces of a pattern molded using the composition than in an interior of the pattern