At present

the operating temperatures of aero-engines and gas turbines have exceeded 1000℃

and the performance of traditional bond coat material MCrAlY has gradually been unable to meet the demand. NiAl intermetallic has high melting point

low density

low cost and excellent oxidation resistance

which offers its great potential in application. However

the high temperature strength of NiAl is low and the adhesion of its oxide scale is poor

so it is compulsory to modify NiAl to enhance its high-temperature performance by doping platinum group elements (Pt

Ru

Pd

etc.)

reactive elements (Hf

Zr

Dy

etc.) and nanocrystalline particles (CeO

2

Al

2

O

3

ZrC

etc.). The different roles of these doping manners are briefly summarized. By doping alon

e or together

the growth rate of TGO can be slowed down

the mutual diffusion coefficient can be reduced

the adhesion of oxide scale can be increased

and the overall performance of NiAl coating can be improved.