Principal Investigator: Dr. Yongming Liu, Associate Professor, Arizona State University, Tempe, AZ, 480-965-6883,firstname.lastname@example.org. Institutional Principal Investigator: Dr. Caglar Oskay, Assistant Professor, Vanderbilt University, Nashville, TN, 615-343-0583,email@example.com. Project Objectives: The overall goal of this project is to develop novel testing and experimentally validated prediction methodologies for creep-dominated creep-fatigue response of structural materials for advanced reactor systems. The investigations will focus on the characterization and testing of Alloy 617, but the proposed testing and life-prediction methodologies are applicable to other structural materials as well. The research objectives in this proposal are: (1) Perform multi-resolution in situ testing and imaging analysis for the fundamental creep-fatigue damage mechanism investigation; (2) Develop a new procedure for creep-fatigue testing at the coupon level and generate database for model validation; (3) Understand the interaction between fatigue damage and creep damage mechanisms based on microstructure simulation. (4) Develop an experimentally validated life prediction model subjected to creep dominated creep-fatigue loading. Proposed methods and potential impacts: A systematic integrated experimental and numerical methodology is proposed. State-of-the-art experimental techniques and advanced numerical analysis are proposed for the creep-fatigue damage investigation at various different scales. The proposed experimental study will use a multi-resolution in situ testing and imaging-based method for the fundamental creep fatigue damage mechanism investigation. In situ scanning electron microscopy testing will used to observed the micro-level creep fatigue damage, such as inter and intragranular slip, crack size and density, cavitation size and density, and the coalesce and interaction of different damage features. At the coupon level, new testing design and procedures will be proposed to promote more creep damage within the testing materials to represent more realistic service conditions. Periodical surface scanning and imaging will be used to quantify the creep fatigue damage at the larger scales. Numerical simulation focuses on the advanced simulation technique for creep-fatigue analysis, which will be led by the Co-PI. This major task includes three sub-tasks: (2.1) Implementation and validation of a microstructure model for creep-fatigue; (2.2) Microstructure simulation of creep-fatigue response; and (2.3) Development of a phenomenological creep-fatigue damage model.
|Effective start/end date||12/16/13 → 2/28/17|
- DOE: Idaho Field Office: $800,000.00