KU Leuven, Belgium
Ali Rauf
Biography
Ali Rauf is a PhD researcher at KU Leuven’s Department of Materials Engineering, where he has been pursuing his doctoral studies since 2022, focusing on fatigue and fracture mechanics of additively manufactured high-performance alloys. His current research investigates the Very-High-Cycle Fatigue (VHCF) behavior and defect-microstructure interactions in laser powder bed fused nickel based superalloys, bridging advanced materials design with structural integrity assessment for aerospace applications. Before joining KU Leuven, Ali built extensive experience in the aviation sector, where he worked on a range of structural and maintenance engineering projects involving turbine materials, component reliability, and failure analysis. His professional background encompasses practical and analytical expertise in aerospace materials, inspection technologies, and mechanical integrity evaluation skills that now enrich his academic investigations into additive manufacturing and fatigue life prediction. Ali’s research interests include additive manufacturing (AM) of superalloys, fatigue and fracture mechanics, defect characterization via micro-XCT and EBSD, and finite element modeling of damage mechanisms. He aims to translate advanced material processing and characterization insights into real-world solutions for safer and more durable aerospace components.
Conferences
Room |
Date |
Hour |
Subject |
|---|---|---|---|
| Room 6 |
25-03-2026 |
5:40 pm – 6:00 pm |
75 Influence of artificially seeded defects on the VHCF behavior of IN-718 fabricated by L-PBF under Nitrogen Shielding |
Conferences Details
75 Influence of artificially seeded defects on the VHCF behavior of IN-718 fabricated by L-PBF under Nitrogen Shielding
The increasing adoption of Additive Manufacturing (AM) for complex IN-718 components necessitates guaranteed durability in the Very-High-Cycle Fatigue (VHCF) regime (exceeding 109 cycles). Critically, VHCF life in AM-ed materials is exquisitely sensitive to process induced defects and non-metallic inclusions. This investigation systematically evaluates this challenge by examining how variations in defect type govern the VHCF response under nitrogen shielding by artificially inducing defects by varying volumetric energy density (VED). To establish a comprehensive process-defect-fatigue nexus, three distinct VED levels (low, nominal, and high) were deliberately employed to generate two primary defect types: planar lack-of-fusion at low VED and keyhole porosity at high VED. The resulting microstructure, defect morphology, and inclusion chemistry were meticulously characterized using X-ray computed tomography (XCT), electron backscatter diffraction (EBSD), and coupled scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS). Fatigue performance was assessed using ultrasonic fatigue testing (20 kHz, R=−1) at room temperature. Post-mortem fractography, coupled with the Murakami area criterion, was employed to quantify the local driving forces governing crack initiation. The nominal VED processing window yielded the most consistent and longest fatigue lives, serving as the benchmark with the crack initiations from subsurface inclusions, porosity along with crystallographic facets. In contrast, both low and high VED conditions severely depressed the S–N curve and significantly increased scatter due to their characteristic defects along with the presence of inclusions. This research establishes the boundaries and quantitative data essential for qualifying L-PBF IN-718 for reliable long-duration service applications.
Keywords: L-PBF; Nickel based superalloy; Shielding gas; IN-718; AM Process parameters; VHCF
