Nimonic90 / UNS N07090

Nimonic90 alloy overview:

This alloy is an age-strengthened cobalt-nickel-based deformed high-temperature alloy, which contains a higher amount of cobalt and a variety of strengthening elements. Corrosion resistance, high fatigue strength under repeated action of cold and heat, and good formability and weldability. Used in turbine engine turbine disks, blades, high-temperature fasteners, clamps, seals and elastic components.

 

Nimonic90 alloy chemical composition:

%	Ni	Co	Cr	Fe	Zr	B	C
Min.	margin	15.0	18.0
Max.		21.0	21.0	1.5	0.15	0.02	0.13
%	Mn	Si	S	P	Cu	Al	Ti
Min.						1.0	2.0
Max.	0.4	0.8	0.015	0.02	0.2	2.0	3.0

 

Nimonic90 alloy physical properties

density g/cm3	melting point ℃
8.2	1400

 

Nimonic90 alloy mechanical properties (minimum of mechanical properties detected at 20 ℃)

tensile strength σb/MPa	yield strength σp0.2/MPa	MPa Elongation  σ5 /%
820	590	8

 

Microstructure of Nimonic90 alloy

The main strengthening phase of this alloy is γ'-Ni3 (Ti, Al), which is precipitated in the crystal as square particles of different sizes. This shape of γ 'phase can also be seen on the grain boundaries. Discontinuous chain-like precipitation.

 

Nimonic90 alloy process performance and requirements

1. The alloy is prone to internal cracks during forging, allowing heavy hammer to strike. The temperature of the ingot furnace is not higher than 700 ℃, and the low temperature area is preheated for 20-30 minutes, the final heating temperature is 1150 ℃ -1180 ℃, the forging temperature is not lower than 1050 ℃, and the final forging temperature is not lower than 950 ℃.

2. The average grain size of the alloy is closely related to the degree of deformation of the forging and the final forging temperature.

3. The alloy can be inert gas shielded tungsten arc welding and flash butt welding in the solid solution state.

GH93 is a precipitation-hardened nickel-based alloy containing higher cobalt and chromium, which has higher strength and better structural stability. It is used below 815 ° C and has good comprehensive properties. Turbine blades for aircraft engines, turbine disks and fasteners for small engines. The alloy has good hot working plasticity, and can be used for plate, bar and forging.