Self-healing environmental barrier coating
An environmental barrier coating, comprising a substrate containing silicon; an environmental barrier layer applied to the substrate; the environmental barrier layer comprising an oxide matrix; an oxidant getter phase interspersed throughout the oxide matrix; and a self-healing phase interspersed throughout the oxide matrix.
1. An environmental barrier coating system, comprising:
a substrate containing silicon;
an environmental barrier layer applied to said substrate; said environmental barrier layer comprising an oxide matrix;
an oxidant getter phase interspersed throughout said oxide matrix; and
a self-healing phase interspersed throughout said oxide matrix; wherein said self-healing phase comprises a composition of CaO-AlO 1.5 -SiO 2 in the ranges 1-25 mol % CaO, 1-25 mol % AlO 1.5 , 50-99 mol % SiO 2 .
2. The environmental barrier coating system of claim 1 , wherein said substrate comprises a ceramic matrix composite material.
3. The environmental barrier coating system of claim 1 , wherein said environmental barrier layer comprises a SiO 2 rich phase.
4. The environmental barrier coating system of claim 1 , wherein said self-healing phase comprises a glass phase.
5. The environmental barrier coating system of claim 1 , wherein said oxidant getter phase comprises Si x O y C z where 0.5≤x <1; 0≤y <2; 0≤z <2.
6. The environmental barrier coating system of claim 1 , wherein said self-healing phase comprises a material having properties of being in thermodynamic equilibrium with a SiO 2 during operation at predetermined temperatures.
7. The environmental barrier coating system of claim 1 , wherein said self-healing phase comprises a material having properties of flowing into cracks formed in said oxide matrix during operation at predetermined temperatures.
8. The environmental barrier coating system of claim 1 , wherein said self-healing phase comprises a material having properties of flowing into cracks formed in said oxide matrix during operation at predetermined temperatures of from 1800 (982° C.) -3000 degrees Fahrenheit (1650° C.).
9. The environmental barrier coating system of claim 1 , wherein said substrate comprises at least one of a turbine vane and a turbine blade.
10. The environmental barrier coating system of claim 1 , further comprising:
a protective layer applied on said environmental barrier layer.
11. An environmental barrier coating system, comprising:
a substrate containing silicon;
an environmental barrier layer applied to said substrate; said environmental barrier layer comprising an oxide matrix;
an oxidant getter phase interspersed throughout said oxide matrix; and
a self-healing phase interspersed throughout said oxide matrix; wherein said self-healing phase comprises a composition of alkaline earth-alumino silicates in which the total alkaline earth (AE) concentration is between 1-25% AE, 1-25mol % AlO 1.5 , and 50-99mol % SiO 2 .