Abstract
The effectiveness of laser shock peening at both room and elevated temperatures was examined for Inconel 738 low-carbon, a material widely used for gas turbine blades. Laser shock peening was performed with a Nd:YAG laser (wavelength = 532 nm, pulse duration = 8 ns, repetition rate = 10 Hz, top-hat profile) using aluminum foil (100 μm thick) as the protective coating at a laser intensity of 10 GW/cm2 and pass number of 10. As a result of laser shock peening, the surface hardness increased by 38%, and the compressive residual stress increased by approximately eleven times compared with that of the unpeened samples. A low cycle fatigue test was performed at room temperature and elevated temperature (850 °C) under strain control. At room temperature, the fatigue life of laser shock-peened samples increased by approximately 2.4 times that of the unpeened samples. At the high temperature of 850 °C, the fatigue life of the laser shock peened samples was overall similar to that of the unpeened samples, either slightly higher or lower depending on the applied total stress level. The results showed that laser shock peening is beneficial for enhancing fatigue strength at low temperatures, but its effectiveness largely disappears at a temperature as high as 850 °C, possibly owing to severe thermal relaxation.
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.