摘要 |
Method for making barrier coatings 12 such as thermal or environmental barrier coatings on turbine components, said coating including a taggant 26. The method comprises providing a barrier coating and adding from 0.01 mol% to 30 mol% of a taggant to the barrier coating. The taggant comprises a rare earth element selected from lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, ytterbium, and lutetium, salts thereof, silicates thereof, oxides thereof, zirconates thereof, hafnates thereof, titanates thereof, tantalates thereof, cerates thereof, aluminates thereof, aluminosilicates thereof, phophates thereof, niobates thereof, borates thereof, and combinations thereof. The taggant changes the colour of the coating. The barrier coating can be deposited by doping a coating powder with taggant or adding the taggant to a deposition slurry. |