The University of Virginia School of Engineering will soon welcome Tao Sun to the Department of Materials Science and Engineering's faculty. Sun has a distinguished record of achievement as a member of Argonne National Laboratory and beamline scientist at the Advanced Photon Source, a national scientific user facility funded by the U.S. Department of Energy and housed at Argonne. During his tenure, Sun succeeded in proving the value of synchrotron X-ray techniques in additive manufacturing. These techniques characterize materials' transformation during the 3-D printing process with very high spatial and temporal resolution. In addition to running his lab at UVA Engineering, Sun will leverage his experience at Argonne to expose his students to the resources and capabilities of the national laboratory system. Sun credits UVA Engineering's research strength in additive manufacturing, and faculty members' expertise in laser science, physical metallurgy and corrosion, for enticing him away from the Department of Energy complex. “UVA Engineering was among those first to field an additive manufacturing program strongly focused on materials rather than process technology development,†Sun said. Sun will be on Grounds in September, with plans to apply his expertise in X-ray science. He and students working in his lab will watch the laser's interaction with metallic and composite materials, frame-by-frame, in micro-second intervals at the micrometer scale. From these observations, Sun and his team intend to extend the frontiers of knowledge on additive manufacturing, helping create high-fidelity models and developing in-process control systems, with the aim of keeping finished objects free of defects. In addition to X-ray imaging, the Sun Lab team will use a synchrotron X-ray diffraction technique to probe a material's evolution in real time during the additive manufacturing process. “Real-time monitoring helps us understand why some materials are currently not suitable for additive manufacturing. Then we can figure out how to make them printable, by optimizing how we apply heat or tinker with the alloys' composition,†Sun said. More important, Sun asserted, additive manufacturing is an enabling technology for new materials development. The thermal conditions involved in laser- or electron beam-based additive manufacturing are extreme. Rapid heating and cooling processes often create materials with unique phases and microstructures and better properties than conventionally processed materials. “In situ X-ray experiments will help us understand these fundamentals, to facilitate the new materials development,†he said.