High Temperature Oxidation Behavior of Laser Clad NiCrAlY Layer.

Preparation of YSZ/Al2O3 micro-laminated coatings and their influence on the oxidation and spallation resistance of MCrAlY alloys

“…The blank sample shows a relatively rough surface with needle-like and whisker morphologies which are the typical morphology of -Al 2 O 3 . 18,19 Cracks can be identified both on the single-phase YSZ coating and Al 2 O 3 coating and cracking is particularly severe with regard to the Al 2 O 3 coating, which is consistent with the spallation curve. Compared with single-phase YSZ and Al 2 O 3 micro-laminated coatings, the surface of YSZ/Al 2 O 3 composite coatings is much flatter and crack-free, as shown in Fig.…”

High temperature oxidation behavior of laser cladding MCrAlY coatings on austenitic stainless steel

“…[4,[12][13][14]. Many studies of high temperature oxidation in MCrAlY coatings with HVOF, APS, VPS or EB-PVD processes have been published [5,[11][12][13][14]; however, there have been few studies of the high-temperature behavior of NiCrAlY and NiCoCrAlY coatings obtained using laser techniques [15][16][17][18][19][20], and the laser cladding can be an novel alternative to thermal spray process, improving the integrity of the thermal barrier coatings. In this work, the high temperature behavior of MCrAlY laser cladding coatings (NiCoCrAlY and CoNiCrAlY) were investigated using the isothermal oxidation test in static air at 1100 °C for up to 200 h. The possible formation of oxides on the surface and a cross section of the oxidized sample were evaluated by XRD, FESEM and EDS after cutting by FIB.…”

“…the simultaneous formation of a continuous alumina layer preceded by an initial stage of very rapid oxidation of non-protective oxides such as Cr2 O 3 , NiO, CoO, (Ni,Co)Cr 2 O 4 and (Ni,Co)Al 2 O 4[12][13][14][15][16][24][25][26][27]. Y-rich oxide inclusions can appear in the vicinity of initial Y inclusions[13,25] because Y is a reactive element.…”

Influence of TGO Composition on the Thermal Shock Lifetime of Thermal Barrier Coatings with Cold-sprayed MCrAlY Bond Coat

“…The thickness of TGO increases with the thermal exposure time following a parabolic law ( Ref 1,[11][12][13]. Thickness of TGO determines the stresses within YSZ coating, TGO, and the interface of TGO-bond coat (Ref 1).…”