Sebastian Lech

Biography

Sebastian Lech is an assistant professor at AGH University of Krakow in Poland. He graduated with a PhD in Materials Science and Engineering from the same university in 2021, focusing on superalloys and electron microscopy. After graduation, he was a postdoctoral researcher at Johns Hopkins University, Baltimore, US, working on high-entropy alloys, additive manufacturing and high-throughput experiments. In the final year, he was a research scientist combining work in Mitra Taheri's group with an additive manufacturing lab manager role at the Materials Characterization and Processing Centre. After departure from the US in 2025, Sebastian joined Katerina Christofidou's IDEA group at the University of Sheffield as research associate, working on additive manufacturing. His research now is focused on high-throughput materials science through additive manufacturing and materials for extreme environments. Sebastian received the Polish Ministry of Science and Higher Education award for outstanding young researchers in 2025, and authored over 35 peer-reviewed articles. 

Abstract

High-throughput alloy design through directed energy deposition

The vast compositional space of advanced materials presents a significant bottleneck for traditional, time-intensive alloy development. The current timeline for moving a novel alloy from initial concept to industrial consideration takes years, even when limited design space is explored. One way to accelerate materials discovery is to use high-throughput methods, including both materials synthesis and characterization. Among available additive manufacturing methods, Directed Energy Deposition (DED) has emerged as a powerful tool for scalable high-throughput alloy design.

This talk explores the use of DED for accelerated alloy design and discovery, leveraging in-situ alloy blending. The combination of CALPHAD computational methods with high-throughput experimental synthesis and characterization techniques (X-ray fluorescence, X-ray diffraction, and electron microscopy) facilitates a comprehensive understanding of the structure-property relationship in advanced alloys. The current results focus on various grades of nickel-based superalloys, demonstrating the application of our methodology to materials with complex chemical composition and microstructure.

Ultimately, this study highlights how integration of computational methods with combinatorial DED and advanced characterization drastically reduces the time from conceptualization to physical validation. The drastic reduction in development time and cost shown here creates an environment for a rapid response to any emerging industrial challenges, de-risking future R&D investments.