Self-healing heat damping layers and method for producing same

Abstract

A method for producing a self-healing heat-insulating layer on a substrate by atmospheric plasma spraying (APS) of a heat-insulating-layer powder. The method includes introducing MoSi2 powder containing aluminum into a heat-insulating layer. The MoSi2 powder contains aluminum in a content of from 2 to 15 wt. %. The MoSi2 powder is used in a mass fraction of between 0.5 and 5 wt. % based on the heat-insulating layer. The method further includes injecting the heat-insulating-layer powder at a first point that is at a distance from a gun in the axial direction and injecting the MoSi2 powder into a plasma jet at a second point that is at a greater distance from the gun in the axial direction. An injection distance (I) of between 20 and 60 mm is set between the first and the second point.

1 . A method for producing a self-healing heat-insulating layer on a substrate by atmospheric plasma spraying (APS) of a heat-insulating-layer powder, the method comprising:
 introducing MoSi 2  powder containing aluminum into a heat-insulating layer, wherein the MoSi 2  powder contains aluminum in a content of from 2 to 15 wt. %, wherein the MoSi 2  powder is used in a mass fraction of between 0.5 and 5 wt. % based on the heat-insulating layer; and   injecting the heat-insulating-layer powder at a first point that is at a distance from a gun in the axial direction and injecting the MoSi 2  powder into a plasma jet at a second point that is at a greater distance from the gun in the axial direction,   wherein an injection distance (I) of between 20 and 60 mm is set between the first and the second point.   
     
     
         2 . The method according to  claim 1 , wherein the heat-insulating-layer powder includes at least one of zirconia with Y 2 O 3 , MgO, CaO or CeO 2  as the stabilizing component, Al 2 O 3 , TiO 2 , mullite, La 2 Zr 2 O 7 , Gd 2 Zr 2 O 7  or Y—Si—O. 
     
     
         3 . The method according to  claim 1 , wherein the MoSi 2  powder has an aluminum content of from 3 to 12 wt. %. 
     
     
         4 . The method according to  claim 1 , wherein the MoSi 2  powder has an additional boron content of up to 2 wt. %. 
     
     
         5 . The method according to  claim 1 , wherein the MoSi 2  powder has an average particle diameter d 50  of between 5 μm and 60 μm. 
     
     
         6 . The method according to  claim 1 , wherein the injection distance (I) is between 30 and 50 mm. 
     
     
         7 . The method according to  claim 1 , wherein (Ar:He) is used as the plasma gas and a current of greater than 400 A is set. 
     
     
         8 . The method according to  claim 1 , wherein the heat-insulating layer is applied to at least one adhesion-promoter layer initially deposited on the substrate. 
     
     
         9 . A heat-insulating layer, comprising:
 a heat-insulating-layer material as a matrix,   MoSi 2  powder in a mass fraction of from 0.5 to 5 wt. % based on the heat-insulating layer, and   aluminum in a mass fraction of from 2 to 12 wt. % based on the MoSi 2  mass fraction.   
     
     
         10 . The heat-insulating layer according to  claim 9 , wherein the MoSi 2  powder has an aluminum content of from 5 to 10 wt. %. 
     
     
         11 . The heat-insulating layer according to  claim 9 , wherein the MoSi 2  powder has an additional boron content of up to 2 wt. %. 
     
     
         12 . The heat-insulating layer according to  claim 9 , wherein the MoSi 2  powder introduced has an average particle diameter d 50  of between 5 μm and 60 μm.