Components and methods of forming protective coating systems on components

A method of forming a protective coating system on a gas turbine engine component, the method comprising:

• preparing a braze mixture comprising silicon powder and a plurality of intermetallic-forming constituents admixed with the silicon powder;
• applying the braze mixture over a surface of the gas turbine engine component;
• and
• heating the braze mixture to at least one predetermined processing temperature sufficient to react the silicon powder with the plurality of intermetallic-forming constituents and produce a braze layer over the gas turbine engine component containing a plurality of different intermetallics and providing a barrier to oxygen diffusion through the braze layer and to the gas turbine engine component.

A method of forming a protective coating system on a silicon-based gas turbine engine component, the method comprising:

• forming an intermetallic-containing braze layer over the silicon-based gas turbine engine component, the intermetallic-containing braze layer comprising:
• a silicon matrix;
• and
• a plurality of metallic elements bonded to substantially all of the silicon included within the silicon matrix, the plurality of metallic elements forming a plurality of intermetallics with the silicon and distributed throughout the microstructure of the braze layer to provide a barrier to oxygen diffusion through the braze layer and to the silicon-based gas turbine engine component;
• forming at least one of an oxide scale layer, an environmental barrier coating, and a thermal barrier coating over the braze layer.