The preparation and hot corrosion resistance of gradient NiCoCrAlYSiB coatings

Surface energy of M2AC(0001) determined by density functional theory (M=Ti,V,Cr; A=Al,Ga,Ge)

“…Since the surface is terminated with Al, Ga and Ge, the onset of oxidation may be governed by the interaction with A elements. It is well known that Al-containing phases, such as TiAl [37], CoAl [38], AlGaN/GaN heterostructures [39] and NiCoCrAlYSiB [40] form Al 2 O 3 surface passivating layer hindering further oxidation. Hence, the Al terminated M 2 AlC(0 0 0 1) may also be passivated by Al 2 O 3 .…”

Corrosion behavior of plasma-sprayed Al2O3–Cr2O3 coatings in hot lithium molten salt

“…As shown in Fig. 2a, the aluminized bond coat showed a lamellar structure which is a characteristic of plasma-sprayed coating, including pores, unmelted particles and oxide inclusions [14][15][16][17]. The assprayed microstructure of the top coat exhibited imperfections such as pores and microcracks which are a complex function of the spraying parameters (Fig.…”

“…7, the scale was mainly composed of TiO 2 , Cr 2 O 3 , and Al 2 O 3 . It is a typical appearance of hot corrosion, porous oxide, internal oxidation, and an alloy depleted layer [16]. The elemental distribution shows the outer scale mainly composed of TiO 2 and Al 2 O 3 , and intermediate layer rich in chromium, and an Al 2 O 3 scale formed close to the substrate.…”

“…In this work, a plasma-sprayed NiCrAlY bond coat and Al 2 O 3 -Cr 2 O 3 top coat were selected due to the excellent resistance to erosion and thermal difference [14][15][16][17]. The hot corrosion behaviors of an aluminized NiCrAlY and Al 2 O 3 -Cr 2 O 3 coated IN713LC in the presence of lithium molten salt have been investigated under simulated electrolytic reduction conditions.…”

Corrosion behavior of Ni-based structural materials for electrolytic reduction in lithium molten salt

“…Hence, this microstructural observation indirectly confirms the enhancement of interfacial strength between the oxide layer and the base metal after the heat treatment of the specimen. The weight loss of the specimens with time was attributed to the cracking of the protective layer, leading to spallation from the base metal surface as well as dissolution of the scales and other corroded products [15]. Therefore, it was thought that the formation of the corrosion layer and its adherence to the base metal significantly influenced the weight variation of the specimens.…”