Cmc turbine engine blades and a rotor wheel for a turbine engine and a turbine engine integrating them

Abstract

A rotor wheel of a turbine engine includes a plurality of CMC blades each having a first portion constituting a blade airfoil and root and made as a single piece with a second portion forming an outer platform. The blades are held under twisting prestress by mutual engagement via contact zones between the outer platforms of adjacent blades, and the contact zones that are situated on opposite sides of the outer platform of a blade are defined by at least one insert that is integrated in the outer platform and that is, for example, made of a carbon-based material.

1 . A turbine engine rotor wheel including a plurality of blades of composite material comprising fiber reinforcement densified with a ceramic matrix, each blade having a first portion constituting a blade airfoil and root and being formed as a single piece together with at least one second portion forming an outer platform, in which wheel the blades are prestressed in twisting about longitudinal axes and are held under prestress by mutual engagement via contact zones between the outer platforms of adjacent blades, the contact zones situated on opposite sides of the outer platform of a blade being defined by at least one insert integrated in the outer platform of the blade. 
     
     
         2 . A rotor wheel according to  claim 1 , wherein said at least one insert is made of a carbon-based material. 
     
     
         3 . A wheel according to  claim 2 , wherein said at least one insert is made essentially of a material selected from monolithic graphite and a carbon/carbon type composite material. 
     
     
         4 . A wheel according to  claim 1 , wherein each blade outer platform is provided with two inserts on respective sides of the outer platform. 
     
     
         5 . A wheel according to  claim 1 , wherein each blade outer platform is provided with an insert that extends from one side of the outer platform to the other. 
     
     
         6 . A turbine engine including at least one rotor wheel according to  claim 1 . 
     
     
         7 . A turbine engine blade made of composite material comprising fiber reinforcement densified with a ceramic matrix, the blade having a first portion constituting a blade airfoil and root and being formed as a single piece together with at least one second portion forming an outer platform, wherein the outer platform presents contact zones on opposite sides for coming into contact with the outer platforms of adjacent blades when the blade is integrated in a rotor wheel of a turbine engine, and the contact zones are defined by at least one insert integrated in the outer platform. 
     
     
         8 . A blade according to  claim 7 , wherein said at least one insert is made of a carbon-based material. 
     
     
         9 . A blade according to  claim 8 , wherein said at least one insert is made essentially of a carbon/carbon type material. 
     
     
         10 . A blade according to  claim 7 , wherein the outer platform is provided with two inserts arranged on opposite sides of the outer platform. 
     
     
         11 . A blade according to  claim 7 , wherein the outer platform is provided with an insert that extends from one side of the outer platform to the other.