||Nickel base superalloy
|Composition (% by mass):
||57.4 Ni, 16 Cr, 15 Co, 3 Mo, 1 W, 5 Ti, 2.5 Al, 0.1 C
||862 MPa, 125 ksi
||1104 MPa, 160 ksi
|Drilling machinability rating:**
|Turning machinability rating:***
**Comparative value for use with superalloy tables in Machining Navigator drilling catalogues
***For use with superalloy cutting speed tables in Machining Navigator turning catalogues
****Material specific values to calculate power demand for machining operations in turning and milling
Milling cutting data can be found in Machining Navigator catalogues with material group 21 data listings
General material properties
Udimet 720 is a nickel base superalloy that is solid solution strengthened with alloying elements such as tungsten and molybdenum. It can be further hardened with heat treatment. This alloy features good oxidation and corrosion resistance at high temperature.
Typical application areas
Because of its excellent high temperature strength, combined with good oxidation and corrosion resistance, Udimet 720 is commonly used in both disc and turbine blade applications.
General machining characteristics
Udimet 720 is a difficult material to machine due to its strength, low thermal conductivity, abrasiveness, and, especially, tendency to work harden. Work hardening occurs whenever a tool makes a cut. The machined surface of the component is deformed slightly during the cut, leaving it substantially harder than the original material. This results in notching and chipping during subsequent machining passes. Sharper, more positive cutting edges, typically PVD (physical vapor deposition) coated, reduce this phenomenon, and are therefore preferred.
An additional complication, related to the toughness of this alloy, is that chips are difficult to break. All of these factors dictate that a correct combination of tool, tool geometry, cutting data and tool path is essential for good machining results. Because of this alloy’s low thermal conductivity, heat build-up is a problem. Therefore, correct coolant application is necessary.
Good quality coolant is strongly preferred.
For cutting data see Machining Navigator.