Microstructural Response and Strain Hardening in Deep Cold Rolled Nickel-based Superalloy for Aerospace Application

Microstructural Response and Strain Hardening in Deep Cold Rolled Nickel-based Superalloy for Aerospace Application
Title:
Microstructural Response and Strain Hardening in Deep Cold Rolled Nickel-based Superalloy for Aerospace Application
Other Titles:
Procedia CIRP
Keywords:
Publication Date:
06 June 2018
Citation:
Dharmesh Kumar, Sridhar Idapalapati, Wang Wei, Microstructural Response and Strain Hardening in Deep Cold Rolled Nickel-based Superalloy for Aerospace Application, Procedia CIRP, Volume 71, 2018, Pages 374-379, ISSN 2212-8271, https://doi.org/10.1016/j.procir.2018.05.044.
Abstract:
Fatigue crack resistance is a critical factor for the performance of aero-engine components. Deep cold rolling (DCR) is one promising surface enhancement technique, as it generates deep compressive residual stresses with the good surface finish. In this work, the influence of DCR process on the microstructure and mechanical properties of nickel-based superalloy (Udimet 720Li) was investigated. After DCR process, a deep layer of compressive residual stress up to 1mm was observed, which agrees well with the depth profile of Vickers micro-hardness. Statistical analysis of Grain Orientation Spread (GOS) in the Electron Back Scattered Diffraction (EBSD) map also shows the presence of strain hardening layer after the DCR process. Results are discussed with a focus on the strengthening mechanism through grain refinement, the addition of Low Angle Grain Boundaries (LAGBs), and intragranular deformation in the sub-surface. Overall, this fundamental understanding could shed light on a new pathway to develop nickel-based superalloys with an excellent mechanical performance for aerospace applications.
License type:
http://creativecommons.org/licenses/by-nc-nd/4.0/
Funding Info:
The authors would like to thank Nanyang Technological University (NTU), Singapore and Advanced Remanufacturing and Technology Centre (ARTC) for providing research funding support to this project, and Rolls-Royce® for providing the raw materials for testing. D. Kumar thanks NTU for the financial support in the form of NTU Research Scholarship. I. Sridhar thanks the project agreement with ARTC (SKMBT_42316032113520).
Description:
ISSN:
2212-8271
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