Ceramic matrix composite component with coating

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.

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.