Multilayered erosion resistant coating for gas turbines

An erosion-resistant coating system for use on an engine component having an outer surface that is configured to be exposed to a first plurality of particles impinging against the outer surface at an angle within a first angle range and a second plurality of particles impinging against the outer surface at an angle in a second angle range that is different than the first angle range, the system comprising:

• a bond layer overlying the engine component outer surface, the bond layer comprising a first material having an amorphous structure;
• a first erosion-resistant layer overlying the bond layer, the first erosion-resistant layer comprising a first material having a first predetermined crystallographic structure that is not the amorphous structure and that is more resistant to erosion by particles impinging the component outer surface at a first angle within the first angle range than by particles impinging the component outer surface at a second angle within the second angle range;
• an interlayer overlying the first erosion-resistant layer, the interlayer comprising a second material having an amorphous structure;
• and
• a second erosion-resistant layer overlying the interlayer, the second erosion-resistant layer comprising a second material having a second predetermined crystallographic structure that is different from the first predetermined crystallographic structure, is not the amorphous structure, and that is more resistant to erosion by particles impinging the component outer surface at a third angle within the second angle range than by particles impinging the component outer surface at a fourth angle within the first angle range.