Casting slurry for the production of shell molds

Abstract

A casting slurry for producing shell molds for casting parts includes a metal alloy, the slurry includes powder particles and a binder, the binder includes colloidal yttrium oxide, and the powder particles includes calcia-stabilized zirconia.

1 . A casting slurry for producing shell molds for casting parts comprising a metal alloy, the slurry comprising powder particles and a binder, characterized in that the binder comprises colloidal yttrium oxide, and in that the powder particles comprise calcia-stabilized zirconia, a mass ratio of the calcia-stabilized zirconia in the slurry being comprised between 65% and 75%. 
     
     
         2 . The slurry as claimed in  claim 1 , the slurry being a contact slurry configured to come into contact with the metal of the part to be molded. 
     
     
         3 . The slurry as claimed in  claim 1 , wherein the mass content of calcium oxide in the calcia-stabilized zirconia is comprised between 1% and 20%. 
     
     
         4 . The slurry as claimed in  claim 1 , wherein the viscosity of the slurry is comprised between 0.1 and 2 Pa.s. 
     
     
         5 . The casting slurry as claimed in  claim 1 , configured for the production of shell molds for casting parts comprising a titanium aluminide-based metal alloy. 
     
     
         6 . Use of the casting slurry as claimed in  claim 1  for the production of a shell mold. 
     
     
         7 . A process for producing a shell mold for casting parts, the process comprising the steps of:
 providing a model of a part to be produced;   dipping the model in a contact slurry as claimed in  claim 1 ;   sandblasting the dipped model in a contact sand comprising yttrium oxide;   drying the layer obtained by the preceding steps;   dipping the model in a reinforcement slurry, sandblasting the model dipped in a reinforcement sand, and drying the layer obtained, until a desired shell mold thickness is obtained;   removing the part model.   
     
     
         8 . A shell mold obtained by the process as claimed in  claim 7 . 
     
     
         9 . The slurry as claimed in  claim 1 , wherein the mass ratio of the calcia-stabilized zirconia in the slurry is between 68% and 72%. 
     
     
         10 . The slurry as claimed in  claim 1 , wherein the mass ratio of the calcia-stabilized zirconia in the slurry is equal to 70%.