Gamma prime phase-containing nickel aluminide coating

A coating system on a substrate, the coating system comprising a coating consisting essentially of the gamma prime-Ni3Al intermetallic phase and the beta-NiAl intermetallic phase, the coating having an average aluminum content of 14 to 30 atomic percent and an average platinum-group metal content of at least 1 to less than 10 atomic percent, the balance of the coating being nickel, one or more of chromium, silicon, tantalum, and cobalt, optionally one or more of hafnium, yttrium, zirconium, lanthanum, and cerium, and incidental impurities.

A coating system on a substrate, the coating system comprising a coating consisting essentially of gamma prime-Ni3Al intermetallic phase and either beta-NiAl intermetallic phase or gamma-Ni phase, the coating having an average aluminum content of 26 to 30 atomic percent and an average platinum-group metal content of at least 1 to less than 10 atomic percent, the balance of the coating being nickel, one or more of chromium, silicon, tantalum, and cobalt, optionally one or more of hafnium, yttrium, zirconium, lanthanum, and cerium, and incidental impurities.

A coating system on a substrate, the coating system comprising a coating consisting essentially of gamma prime-NI3Al intermetallic phase and either beta-NiAl intermetallic phase or gamma-Ni phase, the coating having an average aluminum content of 14 to 30 atomic percent and an average platinum-group metal content of at least 1 to less than 10 atomic percent, about 0.1 to about 5 atomic percent tantalum, the balance of the coating being nickel, one or more of chromium, silicon, and cobalt, optionally one or more of hafnium, yttrium, zirconium, lanthanum, and cerium, and incidental impurities.

A coating system on a substrate, the coating system comprising a coating consisting essentially of gamma prime-Ni3Al intermetallic phase and either beta-NiAl intermetallic phase or gamma-Ni phase, the coating having an average aluminum content of 14 to 30 atomic percent and an average platinum-group metal content of at least 1 to less than 10 atomic percent, about 0.5 to about 20 atomic percent cobalt, the balance of the coating being nickel, one or more of chromium, silicon, and tantalum, optionally one or more of hafnium, yttrium, zirconium, lanthanum, and cerium, and incidental impurities.

A coating system on a superalloy substrate of a gas turbine engine component, the coating system comprising an overlay coating consisting essentially of gamma prime-Ni3Al intermetallic phase and either beta-NiAl intermetallic phase or gamma-Ni phase, the overlay coating having an average aluminum content of 14 to 30 atomic percent and an average platinum-group metal content of at least 1 to less than 10 atomic percent, 0.01 to about 2 atomic percent hafnium, the balance of the overlay coating being nickel, and either chromium or silicon, and incidental impurities, the overlay coating containing at least 50 volume percent of the gamma-prime-Ni3Al intermetallic phase, the coating having an outer surface region with a platinum-group metal content of less than the average platinum-group metal content in the coating.