Overview
Oxide dispersion strengthened (ODS) austenitic steels are endowed with high temperature strength and resistance to creep, fatigue, oxidation and hot corrosion. Hence, these steels are potential candidates for the ultra-super critical steam turbines, which are exposed to temperatures of about 700 C. The high temperature properties of ODS steels are due to the fine-grained microstructure, stable nano sized oxide(Y-Ti-O complex) dispersoids and stability of the microstructure at high temperatures. ARCI has embarked on major program for development and demonstration of technologies for the manufacture of blades for ultra-super critical steam and gas turbines.
Key Features
High operating temperature of 650-700 °C
High yield strength of 300 MPA at 700° C
Good oxidation resistance
Potential candidates to replace nickel based super alloys
Potential Applications
Blades for ultra-super critical steam turbines
High pressure compressor and low pressure turbine blades of gas turbines
Other high temperature applications
Status
Basic concepts and understanding of underlying scientific principles
Short listing possible applications
Research to prove technical feasibility for targeted application
Coupon level testing in stimulated conditions
- S. Ganesh, P. Sai Karthik, M. Ramakrishna, A.V. Reddy, S.B. Chandrasekhar, R. Vijay, “Ultra-high strength oxide dispersion strengthened austenitic steel”, Materials Science and Engineering A, 814 (2021) 141192.
P.S. Ninawe, S. Ganesh, P. Sai Karthik, S.B. Chandrasekhar, R. Vijay, “Microstructure and mechanical properties of spark plasma sintered austenitic ODS steel”, Advanced Powder Technology, 33 (2022) 103584.
P. Sai Karthik, S. Ganesh, P. S. Ninawe, M. Battabyal, S. B. Chandrasekhar, R. Vijay, “Microstructure and mechanical properties of austenitic ODS steel processed using Ni–20Cr”, Journal of Materials Research, DOI:10.1557/s43578-023-00938-6, 2023