Bondcoats having a metalloid-based material matrix
Coated components are provided that include a substrate having a surface; a bondcoat over the surface of the substrate; a thermally grown oxide layer over the bondcoat; and an environmental barrier coating over the thermally grown oxide layer. The bondcoat includes a plurality of core-shell particulates and a plurality of oxide-sintering aid globular phases dispersed within a metalloid-based material matrix. The plurality of core-shell particulates have a shell comprising a metalloid oxide around a core comprising a metalloid-based material. The plurality of oxide-sintering aid globular phases includes a mixture of the metalloid oxide and a sintering aid.
1 . A coated component, comprising:
a substrate having a surface; and
a bondcoat over the surface of the substrate, wherein the bondcoat comprises a plurality of core-shell particulates and a plurality of oxide-sintering aid globular phases dispersed within a metalloid-based material matrix, wherein the plurality of core-shell particulates have a shell comprising a metalloid oxide around a core comprising a metalloid-based material, and wherein the plurality of oxide-sintering aid globular phases includes a mixture of the metalloid oxide and a sintering aid.
2 . The coated component of claim 1 , wherein the metalloid oxide comprises silicon oxide, and wherein the metalloid-based material comprises silicon and silicon oxide.
3 . The coated component of claim 2 , wherein the bondcoat has a degree of oxidation that is 5% by volume to 40% by volume.
4 . The coated component of claim 1 , wherein the oxide-sintering aid globular phases comprise a sintering aid, wherein the sintering aid is present in an amount of 0.03% by weight to 1.0% by weight of the bondcoat.
5 . The coated component of claim 1 , wherein the oxide-sintering aid phase comprises a sintering aid selected from the group consisting of Al, B, Ca, Cu, Fe, Hf, Mg, Mn, N, Ni, P, O, Ti, V, Zr, Au, Cr, Sn, In, Bi, Ga, La, Ce, Sb, As, Hf, a mullite-based material, and a combination thereof.
6 . The coated component of claim 5 , wherein at least two sintering aids are present in the oxide-sintering aid globular phases, wherein the at least two sintering aids comprise a combination of Fe and Al, a combination of Fe and Ni, a combination of Fe and Ca, or a combination of Fe, Al, Ca, Ni, Zr, and Cu.
7 . The coated component of claim 5 , wherein at least two sintering aids are present in the oxide-sintering aid globular phases, and wherein each sintering aid is present, independently, in an amount of 0.001% by weight to less than 0.999% by weight.
8 . The coated component of claim 1 , wherein the plurality of core-shell particulates has an average sphericity of 1.0 to 1.8.
9 . The coated component of claim 1 , wherein the plurality of core-shell particulates has an average diameter that is 3 μm or less.
10 . The coated component of claim 1 , wherein the bondcoat comprises defects defining 15% by volume or less.
11 . The coated component of claim 10 , wherein the defects have an average diameter that is less than 1 μm.
12 . The coated component of claim 1 , wherein the bondcoat has a thickness of 25 μm to 150 μm.
13 . The coated component of claim 1 , wherein the metalloid-based material matrix comprises substantially pure silicon.
14 . The coated component of claim 1 , wherein the metalloid-based material matrix defines a continuous phase.
15 . The coated component of claim 1 , wherein the substrate comprises silicon-based substrate.
16 . The coated component of claim 15 , wherein the substrate comprises a ceramic matrix composite.
17 . The coated component of claim 16 , wherein the ceramic matrix composite comprises silicon carbide.
18 . The coated component of claim 1 , further comprising:
an environmental barrier coating over the bondcoat.
19 . The coated component of claim 18 , further comprising:
a thermally grown oxide layer over the bondcoat, wherein the thermally grown oxide layer is positioned between the bondcoat and the environmental barrier coating.
20 . The coated component of claim 19 , wherein the thermally grown oxide layer has a thickness of 1 μm to 10 μm.