Description:

ME Seminar: Tao Sun
X-ray Vision of Metal Additive Manufacturing

Monday, October 20, 2025
3:00 PM
L211 Tech

Zoom Link: https://northwestern.zoom.us/j/96276860893

Additive manufacturing (AM, or 3D printing) is a suite of disruptive technologies that build three-dimensional objects by adding materials layer by layer based on digital designs. In particular, metal AM has developed rapidly in the last three decades and found many applications in medical, aerospace, energy, and defense sectors. Numerous 3D printer manufacturers have emerged, and new business models centered on AM are being established across industries. However, despite the excitement surrounding its potential, the qualification and certification of AM parts in risk-averse industries remain significant challenges, hindering the broader adoption of these technologies. This is largely due to the complex interplay of multiple highly dynamic processes inherent to metal AM.

Synchrotron x-ray techniques have emerged as powerful tools for studying metal AM processes. Leveraging high-intensity, high-energy X-ray sources, researchers have investigated a wide range of highly transient phenomena and non-equilibrium structural dynamics in AM using operando X-ray imaging and diffraction techniques. These experiments have advanced the field by:
(i) quantitatively measuring key process and material parameters for model calibration and validation;
(ii) enabling mechanistic studies of defect formation and microstructure evolution; and
(iii) providing high-fidelity ground truth for benchmarking process sensing techniques.

Since the first successful experiment at the Advanced Photon Source in 2016, the research community has expanded rapidly, with operando experiments now conducted at nearly all major synchrotron facilities worldwide and applied across a broad spectrum of AM processes. In this presentation, I will highlight insights from our synchrotron studies on laser powder bed fusion and directed energy deposition, and discuss open questions that could shape the next phase of research.

 
BIO
Dr. Tao Sun is an Associate Professor of Mechanical Engineering at Northwestern University. He earned his B.S. and M.S. in Materials Science and Engineering (MSE) from Tsinghua University and his PhD in MSE from Northwestern University. Dr. Sun conducted postdoctoral research at Argonne National Laboratory, where he later advanced to Assistant Physicist and Physicist positions. In 2019, he began his academic career at the University of Virginia and then joined Northwestern University in 2023.

Dr. Sun’s research expertise spans X-ray science, additive manufacturing, materials characterization, and advanced instrumentation. His team focuses on uncovering the fundamental physics governing energy-matter interactions, heat and mass transfer, multiphase flow, and non-equilibrium material structure evolution in additive manufacturing. Dr. Sun is recognized as a Highly Cited Researcher by Clarivate.