High temperature protective coating

Abstract

The invention relates to a high temperature protective coating based on MCrAlY coating, with M at least one element out of the group of Ni, Co and Fe, for a component of a turbo machine, especially a gas turbine, the coating containing at least at least 1.75 vol.-% chromium borides and the coating consisting of the following chemical composition (in wt.-%): 10-27 Cr; 3-12 Al; 1-4 Si; 0.1-3 Ta; 0.01-3 Y; 0.1-3 B; 0-7 M, with M being a different element out of said group compared to the remainder, and the remainder being M and inevitable impurities. A preferred embodiment is a coating with the following chemical composition: 10-27 Cr; 3-12 Al; 1-4 Si; 0.1-3 Ta; 0.01-3 Y; 0.1-3 B; 0-7 Co and the remainder being Ni and inevitable impurities.

1 . High temperature protective coating based on MCrAlY coating, with M at least one element out of the group of Ni, Co and Fe, for a component of a turbo machine, especially a gas turbine, the coating containing at least 1.75 vol.-% chromium borides and consisting of the following chemical composition (in wt.-%):
 10-27 Cr;   3-12 Al;   1-4 Si;   0.1-3 Ta;   0.01-3 Y;   0.1-3 B;   0-7 M, with M being a different element out of said group compared to the remainder;   the remainder being M and inevitable impurities.   
     
     
         2 . The coating according to  claim 1 , wherein the coating consists of the following chemical composition (in wt.-%):
 10-27 Cr;   3-12 Al;   1-4 Si;   0.1-3 Ta;   0.01-3 Y;   0.1-3 B;   0-7 Co;   the remainder being Ni and inevitable impurities.   
     
     
         3 . The coating according to  claim 1 , wherein the coating consists of the following chemical composition (in wt.-%):
 10-27 Cr;   3-12 Al;   1-4 Si;   0.1-3 Ta;   0.01-3 Y;   0.1-3 B;   0-7 Ni;   the remainder being Co and inevitable impurities.   
     
     
         4 . The coating according to  claim 1 , wherein the Cr content is 21-25 wt.-%, preferred 22-25 wt.-%. 
     
     
         5 . The coating according to  claim 1 , wherein the Al content is 4-6 wt.-%. 
     
     
         6 . The coating according to  claim 1 , wherein the Si content is 1.5-2.6 Si wt.-%. 
     
     
         7 . The coating according to  claim 1 , wherein the Ta content is 1.5-3 wt.-%. 
     
     
         8 . The coating according to  claim 1 , wherein the Y content is 0.01-1 wt.-%. 
     
     
         9 . The coating according to  claim 1 , wherein the B content is 0.1-1 wt.-%. 
     
     
         10 . The coating according to  claim 1 , wherein the M content, with M being a different element out of said group compared to the remainder, is 0-1 wt.-%.