DZ422 is a nickel-based precipitation-hardened, directionally solidified columnar high-temperature alloy designed for service temperatures below 1050 °C. It ranks among the highest-performing alloys in its category within China. The alloy exhibits good medium and high-temperature comprehensive properties, along with excellent resistance to both cold and hot fatigue.
The composition includes 1.5% Hafnium (Hf), which enhances the lateral strength of the alloy and contributes to its favorable casting properties. DZ422 can be cast into non-residue directionally solidified hollow blades with complex inner cavities and wall thicknesses as small as 0.5 mm, making it suitable for manufacturing gas turbine rotor blades, guide vanes, and other high-temperature components.
DZ422 has been successfully utilized to manufacture gas turbine rotor blades operating below 1000 °C and guide vanes functioning below 1050 °C in aircraft engines. Its performance has been commendable, and it has garnered recognition in similar applications internationally, where various advanced aircraft engine rotor blades and guide vanes are produced.
To further enhance the alloys properties, the surface of the parts can be treated with aluminum (Al) or aluminum-silicon (AlSi) coatings, significantly improving oxidation resistance and thermal corrosion resistance. Following long-term aging at temperatures of 850 °C to 950 °C, a small amount of Y phase precipitates, contributing to the alloys durability.
