Abstract
Effects of temperature, frequency, and cycles with superimposed hold times are evaluated in Ti-1100 in order to study the complex creep-fatigue-environment interactions in this material. Crack growth rate tests conducted at a cyclic loading frequency of 1.0 Hz show that raising the temperature from 593 to 650°C has only a slightly detrimental effect on crack growth rate, although these temperatures produce growth rates significantly higher than at room temperature. From constant △K tests, the effects of temperature at constant frequency show a minimum crack growth rate at 250°C. From the minimum crack growth rate at 250°C, the crack growth rate increases linearly with temperature. Increases in frequency at constant temperatures of 593 and 650°C produce a continuous decrease in growth rate in going from 0.001 to 1.0 Hz, although the behavior is primarily cycle dependent in this region. Tests at 1.0 Hz with superimposed hold times from 1 to 1000 s are used to evaluate creep-fatigue-environment interactions. Hold times at maximum load are found to initially decrease and then increase the cyclic crack growth rate with increasing duration. This is attributed to crack-tip blunting during short hold times and environmental degradation at long hold times. Hold times at minimum load show no change in growth rates, indicating that there is no net environmental degradation to the bulk material beyond that experienced during the baseline 1 Hz cycling.
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.