Transplanted thermal barrier coating system

Abstract

Method for forming a molded part and the molded part. The method includes applying a thermal barrier coating (TBC) system to a sand core; inserting the TBC coated sand core into a mold; and forming a cast iron part in the mold with the inserted TBC coated sand core.

1 . A method for forming a molded part, comprising:
 applying a thermal barrier coating (TBC) system to a sand core;   inserting the TBC coated sand core into a mold; and   forming a cast iron part in the mold with the inserted TBC coated sand core.   
     
     
         2 . The method according to  claim 1 , wherein the TBC system comprises a ceramic layer and a metallic layer. 
     
     
         3 . The method according to  claim 2 , further comprising:
 applying the ceramic layer over the sand core with an air plasma spray thermal spray process; and   applying the metallic layer onto the ceramic layer with the air plasma spray thermal spray process.   
     
     
         4 . The method according to  claim 2 , wherein the ceramic layer is applied as dual layer system with a porous TBC layer applied over the sand core and a non-porous TBC layer applied onto the porous TBC layer. 
     
     
         5 . The method according to  claim 2 , wherein the ceramic layer is applied as a gradient layer with a porosity decreasing from the sand core. 
     
     
         6 . The method according to  claim 2 , wherein the ceramic layer is applied with a thickness between 100 and 1000 microns, preferably between 200 and 800, more preferably between 400 and 500 microns. 
     
     
         7 . The method according to  claim 2 , wherein the metallic layer is applied with a thickness between 100 and 500 microns, preferably between 100 and 350 microns. 
     
     
         8 . The method according to  claim 2 , wherein the metallic layer is applied with a thickness up to 100 microns, preferably up to 50 microns, more preferably between 15 and 30 microns. 
     
     
         9 . The method according to  claim 2 , wherein the ceramic layer comprises yttria stabilized zirconia and the metallic layer comprises a low-alloyed carbon steel that forms a bond coat for the cast iron. 
     
     
         10 . The method according to  claim 3 , wherein, before the ceramic layer is applied, the method further comprises:
 preheating the sand core with the air plasma spray thermal spray process.   
     
     
         11 . The method according to  claim 1 , wherein the TBC system further comprises an adhesion layer. 
     
     
         12 . The method according to  claim 11 , wherein the adhesion layer is applied with a thickness between 20 and 500 microns, preferably between 100 and 400 microns, more preferably between 200 and 350 microns. 
     
     
         13 . The method according to  claim 11 , wherein, before the ceramic layer is applied, the method further comprises:
 applying the adhesion layer onto the sand core with an air plasma spray thermal spray process, wherein the ceramic layer is applied onto the adhesion layer.   
     
     
         14 . The method according to  claim 11 , wherein the adhesion layer comprises at least one of NiC or a mixture of metal and polymer, such as a metal-based polymer composite, preferably an Al based polymer, more preferably at least one of: a MCrAlY based polymer, a NiCrAl based polymer, a NiAl based polymer, an Al-bronze based polymer or an AlSi polyester. 
     
     
         15 . The method according to  claim 1 , wherein the sand core comprises:
 one of silica sand, chromite sand, or zircon sand;   bentonite;   water; and   inert sludge.   
     
     
         16 . The method according to  claim 15 , wherein the sand core further comprises anthracite. 
     
     
         17 . The method according to  claim 15 , wherein the one of silica sand, chromite sand or zircon sand further includes olivine, staurolite, or graphite. 
     
     
         18 . A molded part comprising:
 a cast iron body; and   a TBC system integrally molded with an interior surface of the cast iron body.   
     
     
         19 . The molded part formed by a method according to  claim 1 , the molded part comprising:
 a cast iron body; and   a TBC system integrally molded with an interior surface of the cast iron body.   
     
     
         20 . The molded part according to  claim 18 , wherein the TBC system comprises a ceramic layer and a metallic layer. 
     
     
         21 . The molded part according to  claim 18 , wherein the ceramic layer comprises yttria stabilized zirconia and the metallic layer comprises a low-alloyed carbon steel. 
     
     
         22 . The molded part according to  claim 18 , wherein the TBC system further comprises an adhesion layer. 
     
     
         23 . The molded part according to  claim 22 , wherein the adhesion layer comprises at least one of NiC or a mixture of metal and polymer, such as a metal-based polymer composite, preferably an Al based polymer, more preferably at least one of: a MCrAlY based polymer, a NiCrAl based polymer, a NiAl based polymer, an Al-bronze based polymer or an AlSi polyester. 
     
     
         24 . The molded part according to  claim 18 , wherein the molded part is one of a turbocharger component, an exhaust manifold or a turbo manifold.