Aerospace base material production of wrought products and components represented by 0Cr17Ni4Cu4Nb
Production process of 0Cr17Ni4Cu4Nb
This steel grade is a single process type of martensitic precipitation hardening stainless steel, which consists of low carbon
content, its corrosion resistance and high wear resistance is better than other general martensitic stainless steel. It also has
good resistance to acid, good machinability and insensibility to hydrogen embrittlement. It has the property of acid resistance
of austenite stainless steel and the hardness of martensitic stainless steel. This steel grade is widely used under 400°C working
environment which requireshigh strength and corrosion resistant parts, such as fighter aircraft,fastener of the missile, engine
parts, turbine blade and walve parts etc..
The main strengthen state of this steel part is bronze state, solid solution state is austenitic structure, when the steel being fast
cooled to room temperature, it forms martensite structure which is supersaturated. Through precipitating rich copper epsilon
phase to improve the strength of the steel during the medium temperature aging.
The structure state depends on the ratio of chemical composition and extremely sensitive. Therefore, the strict control of the
chemical composition is very important.
Niobium is ferrite formation element. The presence of the Niobium causes the appearance of delta ferrite. It easily has crack,
the steel processing temperature range in 1000 ~ 1170°C, the best is not lower than 1000°C
This steel is equal to 17-4PH of AMS5643M, USA.
Melting point: 1404～1440°C; Ms 150°C; Mf 32°C
Specific gravity: Solid solution state 7.78 t/m3; Aging state 7.80/m3
The other steel grade as follows: