The Design And Development Of A New Nickel Base Superalloy (wsu 900) For Additive Manufacturing

Husam Alrehaili, Wayne State University

Abstract

Ni-based superalloys are known for their ability to withstand and retain their mechanical and

physical properties at elevated operating temperature, which makes them suitable for gas turbine

and jet engine components. The outstanding properties of Ni-based superalloys have made them

as an interesting candidate to process by Additive Manufacturing (AM). Although some Ni-based

superalloys were successfully processed by AM, others were difficult to process by using

this technique. Therefore, the need for new alloys, developed primarily for AM, has increased.

This work presents a newly developed Ni-based superalloy “WSU 900” that was processed by

using direct laser metal deposition (LMD) coupled with computational thermodynamics and

phase diagram simulations. Microstructural and mechanical properties of the as-deposited and

heat-treated WSU 900 alloy were studied. This new alloy shows good mechanical properties at

room temperature. As-deposited condition revealed YS=951 MPa, UTS=1248 MPa, and

elongation=19.2%. In the heat-treated conditions, 2 hours aged (YS=1076 MPa,

UTS=1401 MPa, and elongation=14.9%), 8 hours aged (YS=1075 MPa, UTS=1376 MPa, and

elongation=14.9 %), and 16 hours aged (YS=1162 MPa, UTS=1469 MPa, and

elongation=11.9%).