Ceramic matrix composite component with coating
A blade outer air seal includes a center web having a radially inner face and a radially outer face, at least one mounting arm extending from the radially outer face, and a coating disposed on the radially inner face. The coating includes an environmental barrier coating layer and an abradable layer disposed on the environmental barrier layer. The abradable layer has a porosity of between about 15 percent and about 40 percent. A gas turbine engine and a method of protecting a blade outer air seal are also disclosed.
1 . A blade outer air seal, comprising:
a center web having a radially inner face and a radially outer face;
at least one mounting arm extending from the radially outer face; and
a coating disposed on the radially inner face, the coating including:
an environmental barrier coating layer, and
an abradable layer disposed on the environmental barrier layer, the abradable layer having a porosity of between about 15 percent and about 40 percent,
wherein the abradable layer comprises silicon oxycarbides.
2 . The blade outer air seal of claim 1 , wherein the environmental barrier coating is nonreactive with respect to calcia-magnesia-alumino-silicate (CMAS).
3 . The blade outer air seal of claim 2 , wherein the environmental barrier coating layer includes at least one refractory metal oxide, and wherein the refractory metal oxide is at least one of HfSiO4 and ZrSiO4.
4 . The blade outer air seal of claim 1 , wherein pores of the abradable layer are configured to receive molten calcia-magnesia-alumino-silicate (CMAS).
5 . The blade outer air seal of claim 1 , wherein the abradable layer includes alkaline earth silicates or alkaline earth aluminosilicates.
6 . The blade outer air seal of claim 1 , wherein the abradable layer includes yttria-stabilized zirconia or alumina-stabilized zirconia.
7 . The blade outer air seal of claim 1 , wherein the abradable layer includes silicon, silicon oxides, or silicon carbides.
8 . The blade outer air seal of claim 1 , wherein the abradable layer includes mullite.
9 . The blade outer air seal of claim 1 , wherein the abradable layer includes titania.
10 . The blade outer air seal of claim 1 , wherein the abradable layer includes chromia.
11 . The blade outer air seal of claim 1 , wherein the abradable layer includes barium-magnesium aluminosilicate.
12 . The blade outer air seal of claim 1 , wherein the abradable layer includes hafnium silicon oxides.
13 . The blade outer air seal of claim 1 , wherein the abradable layer includes alumina-stabilized zirconia.
14 . The blade outer air seal of claim 1 , wherein the abradable layer includes yttria.
15 . A gas turbine engine, comprising:
a turbine section arranged along a central engine axis, the turbine section having a turbine with at least one blade rotatable around the central engine axis, the at least one blade having a tip; and
at least one blade outer air seal arranged radially outward from the tip and attached to an engine static structure, the blade outer air seal including:
a center web having a radially inner face and a radially outer face;
at least one mounting arm extending from the radially outer face, and
a coating disposed on the radially inner face, the coating including:
an environmental barrier coating layer, and
an abradable layer disposed on the environmental barrier layer, wherein the abradable layer has pores and calcia-magnesia-alumino-silicate (CMAS) is disposed in at least some of the pores,
wherein the abradable layer comprises silicon oxycarbides.
16 . The gas turbine engine of claim 15 , wherein the environmental barrier coating is nonreactive with respect to calcia-magnesia-alumino-silicate (CMAS), and wherein the environmental barrier coating layer includes at least one refractory metal oxide, and the refractory metal oxide is at least one of HfSiO4 and ZrSiO4.
17 . A method of protecting a blade outer air seal, comprising:
on a radially inner face of a blade outer air seal, applying a coating, the coating including:
an environmental barrier coating layer, and
an abradable layer the abradable layer having a porosity of between about 15 percent and about 40 percent, wherein pores of the abradable layer are configured to receive molten calcia-magnesia-alumino-silicate (CMAS),
wherein the abradable layer comprises silicon oxycarbides.
18 . The method of claim 17 , wherein the environmental barrier coating is nonreactive with respect to calcia-magnesia-alumino-silicate (CMAS).
19 . The method of claim 18 , wherein the environmental barrier coating layer includes at least one refractory metal oxide.
20 . The method of claim 19 , wherein the refractory metal oxide is at least one of HfSiO4 and ZrSiO4.