Diffusion barrier design against rapid interdiffusion of MCrA1Y and Ni-base material

Arc ion plated-Cr2O3 intermediate film as a diffusion barrier between NiCrAlY and γ-TiAl

“…The main disadvantage of NiCrAlY coatings is that the inward diffusion of Ni from NiCrAlY overlay coating to g-TiAl substrate lead to the formation of brittle interlayers and coating premature failure [4]. This problem might be addressed by the introduction of a diffusion barrier between the coating and substrate to eliminate or greatly reduce the interdiffusion of alloying elements [5][6][7][8][9][10][11][12]. In the present work, an intermediate film of arc ion plated Cr 2 O 3 was employed as a diffusion barrier between g-TiAl and NiCrAlY overlay coating and its effectiveness was investigated.…”

Improvement of oxidation-resistance of NiCrAlY coatings by application of CrN or CrON interlayer

“…Holes, in most of MCrAlY/superalloy systems,[18][19][20] were also observed in the NiCrAlY coatings. 4(b)] shows that the discontinuous alumina predominated in the outmost layer.…”

Investigations on the Deposition and the Efficiency of a Multilayer High Temperature Coating System for Gas Turbine Blades

“…Besides the introduction of innovative cooling techniques, multilayer coating systems have become generally accepted to protect the blades against the high temperatures in the hot gas stream. The system Al-O-N showed promising properties as diffusion barrier at 1100 8C [4,5]. In addition a metallic bond-coat is used to adapt the thermal expansion between blade and ceramic top-coat.…”