Environmental barrier coating with thermal properties
An article according to an exemplary embodiment of this disclosure, among other possible things includes a substrate and a barrier layer on the substrate. The barrier layer includes a bond coat comprising a matrix, diffusive particles disposed in the matrix, and gettering particles disposed in the matrix. At least about 10% of the gettering particles are in a crystalline phase. The article also includes a top coat. An article is also disclosed.
1. An article, comprising:
a substrate; and
a barrier layer on the substrate, the barrier layer including
a bond coat comprising a matrix, diffusive particles disposed in the matrix, and gettering particles disposed in the matrix, wherein at least about 10% of the gettering particles are in a crystalline phase, and
a topcoat,
wherein the bond coat includes a first bond coat layer, a second bond coat layer, and a third bond coat layer, and wherein the first bond coat layer, the second bond coat layer, and the third layer are arranged in an alternating pattern of crystalline gettering particle layers and amorphous gettering particle layers in which substantially all of the gettering particles in each of the first bond coat layer and the third bond coat layer are crystalline or amorphous, and substantially all of the gettering particles in the second bond coat layer are the other of crystalline or amorphous.
2. The article of claim 1 , wherein the first bond coat layer is adjacent the substrate.
3. The article of claim 2 , wherein each of the first and second layers include between about 5 and about 40 percent by volume matrix.
4. The article of claim 3 , wherein the first layer includes the balance crystalline silicon carbide or silicon dioxide gettering particles.
5. The article of claim 3 , wherein the second layer includes between about 55 and 94 percent by volume crystalline silicon carbide or silicon dioxide gettering particles.
6. The article of claim 3 , wherein the second layer includes between about 55 and 94 percent by volume amorphous silicon carbide or silicon dioxide gettering particles.
7. The article of claim 2 , wherein the second layer includes gettering particles having an average maximum dimension between about 1 and about 75 microns.
8. The article of claim 7 , wherein the gettering particles in the second layer have a larger average diameter than the gettering particles in the first layer.
9. The article of claim 1 , wherein the gettering particles are silicon carbide.
10. The article of claim 1 , wherein the gettering particles are silicon oxycarbide.
11. The article of claim 1 , wherein the first bond coat layer is adjacent the substrate.
12. The article of claim 11 , wherein the second layer includes gettering particles having an average maximum dimension between about 1 and about 75 microns, and wherein the gettering particles in the second layer have a larger average diameter than the gettering particles in the first layer.
13. The article of claim 1 , wherein substantially all of the gettering particles in each of the first bond coat layer and the third bond coat layer are crystalline, and substantially all of the gettering particles in the second bond coat layer are amorphous.
14. The article of claim 1 , wherein 100% of the gettering particles in each of the first bond coat layer and the third bond coat layer are amorphous, and 100% of the gettering particles in the second bond coat layer are crystalline.
15. The article of claim 11 , wherein each of the first and second layers include between about 5 and about 40 percent by volume matrix, and the first layer includes the balance crystalline silicon carbide or silicon dioxide gettering particles.
16. The article of claim 15 , wherein the second layer includes between about 55 and 94 percent by volume crystalline silicon carbide or silicon dioxide gettering particles.
17. The article of claim 15 , wherein the second layer includes between about 55 and 94 percent by volume amorphous silicon carbide or silicon dioxide gettering particles.
18. An article, comprising:
a ceramic matrix composite substrate; and
a barrier layer on the substrate, the barrier layer including
a bond coat comprising a silicon dioxide matrix, diffusive particles disposed in the matrix, and silicon carbide or silicon oxycarbide gettering particles disposed in the matrix, wherein at least about 10% of the gettering particles are in a crystalline phase, and
a topcoat,
wherein the bond coat includes a first bond coat layer, a second bond coat layer, and a third bond coat layer, and wherein the first bond coat layer, the second bond coat layer, and the third layer are arranged in an alternating pattern of crystalline gettering particle layers and amorphous gettering particle layers in which substantially all of the gettering particles in each of the first bond coat layer and the third bond coat layer are crystalline or amorphous, and substantially all of the gettering particles in the second bond coat layer are the other of crystalline or amorphous.
19. The article of claim 18 , wherein 100% of the gettering particles in each of the first bond coat layer and the third bond coat layer are crystalline, and 100% of the gettering particles in the second bond coat layer are amorphous.
20. The article of claim 18 , wherein 100% of the gettering particles in each of the first bond coat layer and the third bond coat layer are amorphous, and 100% of the gettering particles in the second bond coat layer are crystalline.