Creep and Fatigue Interaction in the PWA 1484 Single Crystal Nickel-Base Alloy (Preprint)
Abstract
While methods for modeling creep behavior of single crystal turbine airfoils are generally well developed, constant load creep does not fully represent the loading conditions present in a jet engine due to cyclic loading caused by the mission profile and throttle movements. As the aerospace industry seeks to become more accurate in physics-based modeling of materials that are used in turbine blades, creep-fatigue interaction must be incorporated into characterization of turbine blade materials. PWA1484, a second generation single crystal nickel based superalloy that is used for turbine blades in many of today's high performance jet engines was tested in a creep-fatigue environment that is meant to simulate some conditions of the service environment of a jet engine. This research explores the behavior and microstructural evolution of samples of PWA1484 tested in a creep-fatigue environment at 871 deg C in air. It was found that specimens subjected to prior fatigue loading exhibit a smaller region of primary creep that is proportional to the number of prior fatigue cycles, and an accelerated transition to a tertiary creep regime.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2011
- Accession Number
- ADA548467
Entities
People
- Andrew H. Rosenberger
- Anthony N. Palazotto
- Christian J. Pierce
Organizations
- Air Force Research Laboratory