A New Understanding of Creep in Superalloys
August 31, 2020
(a) Sample under load at high temperatures during neutron experiment.
(b) Experimental and predicted back-stress evolution during primary creep.
Scientific Achievement
A theory-derived equation predicting stress re-distribution during primary creep in strengthened Ni-base superalloys was developed and verified experimentally.
Significance and Impact
Creep deformation and failure are important damage modes in Ni-based superalloys used widely in gas turbines. A more accurate prediction of primary creep in such particle-strengthened materials will better guide alloy design and improve component life.
Research Details
- The theory shows that long-range stress within the matrix (“back-stress”) can be estimated from creep experiments if phase-specific elastic strains are obtained from in-situ neutron diffraction experiments.
- GE’s DS GTD-111TM and GTD-444TM superalloys were mounted in a load frame and inductively heated during the in-situ neutron experiment.
“Back-Stress and Its Evolution during Primary Creep in Particle Strengthened Nickel Superalloys”
Sanket Sarkar, Yan Gao, Shenyan Huang, Saswata Bhattacharya, Swapnil Patil and Ramkumar Oruganti,
Crystals, 10(4), 306 (2020). DOI: https://www.mdpi.com/2073-4352/10/4/306
