Precipitation phases in the nickel-based superalloy DZ 125 with YSZ/CoCrAlY thermal barrier coating

Microstructural and morphological evaluation of MCrAlY/YSZ composite produced by mechanical alloying method

“…MCrAlY alloys (where M is Ni, Co or Co +Ni) are one of the most famous protective coating materials applied to protect hot parts of turbines like rotary and static blades against high temperature oxidation and hot corrosion [1,2]. Eddy flows of air in gas turbines, high centrifugal force at blades and solid particles suspended in the air flow are the main failure mechanisms of protective MCrAlY coatings [2].…”

Effect of Re on the precipitation behavior of μ phase in several single crystal superalloys

“…Topologically close packed (TCP) phases, such as r-, l-, P-or R-phase, are critical to the mechanical properties of the aero engine turbine blades made of nickel-based superalloys and have become very common especially in the new generation superalloys with complicated chemical compositions [1][2][3][4][5][6][7][8]. These phases can deteriorate the mechanical properties of superalloys by depleting the matrix of the refractory alloying elements and reduce their solid strengthening effect, delaminating in the fracture zone and acting as initiation sites for fracture at high temperatures [8][9][10][11][12][13][14][15].…”

“…These phases can deteriorate the mechanical properties of superalloys by depleting the matrix of the refractory alloying elements and reduce their solid strengthening effect, delaminating in the fracture zone and acting as initiation sites for fracture at high temperatures [8][9][10][11][12][13][14][15]. Moreover, it found recently that the TCP phases can also form in the secondary reaction zone (SRZ) to affect the coating properties of superalloys [5,6]. Therefore, controlling the alloying elements proportions, especially for the refractory ones, and understanding their interactions on the TCP phase formation in superalloys are extensively concerned to avoid the precipitation of TCP phases.…”

Influences of Cr and Co on the Growth of Thermally Grown Oxide in Thermal Barrier Coating during High-Temperature Exposure

“…Then, a CoCrAlY bond coat was deposited on the K444 superalloy substrate using the EB-PVD technique, and the thickness of the CoCrAlY bond coat was 150 µm. After that, the bond-coated specimen was annealed for 4 h at 1000 • C in a vacuum to acquire a homogeneous microstructure, and then its surface was strengthened by shot-peening [17]. Finally, the YSZ top coat of thickness 60 µm was deposited on the bond-coated specimen by EB-PVD.…”