Method for fabricating an environmental barrier coating on a ceramic matrix composite

A method of fabricating a coating, the method comprising:

• providing a ceramic matrix composite that includes SiC fibers disposed in a SiC matrix;
• depositing a base slurry on the ceramic matrix composite, wherein the base slurry contains, in parts by weight, 35-60 of a metal oxide powder, 5-20 of at least one of silicon carbide powder, silicon nitride powder, or free silicon powder, and 0.2-10 of barium-magnesium-aluminosilicate powder in a first carrier fluid;
• drying the deposited base slurry to produce a base green layer;
• depositing a transition slurry on the base green layer, wherein
• the transition slurry contains, in parts by weight, 35-60 of a metal oxide powder, an amount X1 of at least one of silicon carbide powder, silicon nitride powder, or free silicon powder, an amount X2 of at least one of zirconium carbide powder, zirconium nitride powder, or zirconium oxide powder, and 0.2-10 of barium-magnesium-aluminosilicate powder in a second carrier fluid,
• the total amount of X1+X2 is 5-20, and
• the amount X1 is decreased and the amount of X2 is increased through the deposition of the transition slurry;
• drying the deposited transition slurry to produce a transition green layer;
• and
• forming a consolidated coating on the ceramic matrix composite by heating the base green layer and the transition green layer.