Functionally gradient SiC/SiC ceramic matrix composites with tailored properties for turbine engine applications

A ceramic matrix composite comprising:

• a ceramic matrix;
• a first layer comprising a first plurality of ceramic fibers;
• a second layer comprising a second plurality of ceramic fibers;
• and,
• a coating between the first layer and the second layer, the coating comprising a plurality of regions, the plurality of regions comprising a first region and a second region;
• the first region being defined by a first plurality of layers, the first plurality of layers comprising:
• a first BN layer having a thickness in the range of about 0.3 micron to about 1.0 micron;
• a first Si-doped BN layer having a thickness in the range of about 0.4 micron to about 0.6 micron;
• and,
• a first SiN layer having a thickness in the range of about 0.75 micron to about 1.25 micron;
• the second region being defined by a second plurality of layers, the second plurality of layers comprising:
• a second BN layer having a thickness of less than or equal to about 0.3 micron;
• a second Si-doped BN layer having a thickness of less than or equal to about 0.3 micron;
• a second SiN layer having a thickness of about 0.5micron;
• and
• wherein the ceramic matrix composite is formed by bonding the matrix to the coated fibers.

A ceramic matrix composite comprising:

• a ceramic matrix;
• a first layer comprising a first plurality of ceramic fibers;
• a second layer comprising a second plurality of ceramic fibers;
• and,
• a coating between the first layer and the second layer, the coating comprising a plurality of regions, the plurality of regions comprising a first region and a second region;
• the first region being defined by a first plurality of layers, the first plurality of layers comprising:
• a first BN layer having a thickness in the range of about 0.3 micron to about 1.0 micron;
• a first Si-doped BN layer overlying the first BN layer, the first Si-doped BN layer having a thickness in the range of about 0.4 micron to about 0.6 micron;
• and,
• a first SiN layer overlying the first Si-doped BN layer, the first SiN layer having a thickness in the range of about 0.75 micron to about 1.25 micron;
• the second region being defined by a second plurality of layers, the second plurality of layers comprising:
• a second BN layer having a thickness of less than or equal to about 0.3 micron;
• a second Si-doped BN layer overlying the second BN layer, the second Si-doped BN layer having a thickness of less than or equal to about 0.3 micron;
• a second SiN layer overlying the second Si-doped BN layer, the second SiN layer having a thickness of about 0.5 micron;
• and
• wherein the ceramic matrix composite is formed by bonding the matrix to the coated fibers.