Time lapse in situ X-ray imaging of fatigue cracking events in IN718 alloys at elevated temperatures

AM IN718 superalloy show great potential in aero-engine turbines, which experiences cyclic loading under long-term heat system. However, inherent defects occurring during the AM process can serve as crack initiation sites, leading to diminished high-temperature fatigue properties. Very limited knowledge has been revealed regarding the transition of internal defects to cracks and their role in failure within AM IN718, crucial for accurate strength and life prediction, particularly under extreme high-temperature conditions. In situ SR-µCT provides valuable 3D characterization of damage and crack formation in critical structural materials. Our specialized in situ environment rig allows visual exploration of this sequence at elevated temperatures. This information enables precise monitoring of fatigue crack initiation and propagation, facilitating accurate failure sequence prediction, and ultimately extending the safe operational lifespan of AM IN718 superalloys at elevated temperatures.