Abstract
The microstructures, tensile properties, and fatigue lives of the forged Ti-17 using a 1500-ton forging simulator subjected to different solution treatments and a common aging treatment under both load- and strain-controlled conditions to evaluate high cycle fatigue and low cycle fatigue lives, respectively were examined. Then, the tensile properties, microstructures, and relationships between fatigue lives and the microstructural factors were discussed. The fatigue limit under load-controlled conditions increases with increasing solution treatment temperature up to 1143 K, which is in the (α + β) region. However, it decreases with further increase in the solution treatment temperature to 1203 K in the b region. The fatigue ratio at fatigue limit is increasing with decreasing solution treatment temperature, namely increasing the volume fraction of the primary α phase, and it relates well qualitatively with the volume fraction of the primary α phase when the solution treatment temperature is less than the b transus temperature. The fatigue life under strain-controlled conditions to evaluate the low cycle fatigue life increases with decreasing solution treatment temperature, namely increasing the volume fraction of the primary α phase. The fatigue life under strain-controlled conditions to evaluate the low cycle fatigue life relates well quantitatively with the tensile true strain at breaking of the specimen and the volume fraction of the primary α phase for each total strain range.
Highlights
The amount of usage for commercial aircrafts is recently rapidly increased because CFRP is used for air frame structures [1]
The fatigue limit under load-controlled conditions increases with increasing solution treatment temperature up to 1143 K, which is in the (α + β) region
The fatigue ratio at fatigue limit is increasing with decreasing solution treatment temperature, namely increasing the volume fraction of the primary α phase, and it relates well qualitatively with the volume fraction of the primary α phase when the solution treatment temperature is less than the b transus temperature
Summary
The amount of usage for commercial aircrafts is recently rapidly increased because CFRP (carbon fiber reinforced plastics) is used for air frame structures [1]. Titanium alloys are used in air frames, and in jet engine components such as fans and compressor disks, which function at relatively low temperatures up to 673 K. Fatigue endurance is one of the important factors for the aforementioned engine components. The investigation of fatigue properties of Ti-17 by focusing on their relation with microstructural factors is highly significant. It is important to consider the quantitative relationship between fatigue properties and microstructural factors during the fatigue life estimation of engine components made of Ti-17. In this study, the fatigue properties and microstructures of hot-forged disk-like Ti-17 samples were investigated to define the quantitative relationship between the fatigue properties and the microstructural factors in this study
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.