3D X-ray microscopy (XRM) has rapidly evolved as a leading technique for 3D non-destructive microstructure investigations for a wide variety of material systems. As a core research facility at the University of Michigan’s College of Engineering, the Michigan Center for Materials Characterization (MC)2 provides support for scientific research at micro, nano, and atomic length scales to scientists in academic, government and industry settings. The XRM user base at (MC)2 has grown significantly in the last four years in part because of the rise in 3D printing that has accelerated research into defect behavior in 3D printed parts and the expansion of research and development budgets into battery materials for electric vehicle applications.

In this talk, I will provide insights into how our users have utilized the Xradia 520 Versa powered by ZEISS, for applications spanning aerospace, biomedical and material science engineering. These include failure analysis in composite materials, defect initiation and growth in additively manufactured alloys, 4D studies of grain growth in metallic alloys, and developing novel tools for pre-clinical efficacy testing of percutaneous devices. The multidisciplinary nature of these applications makes the case for wide adoption of laboratory X-ray microscopes in a broad range of industries.

Nancy's Bio
Nancy S. Muyanja received her B.S. degree in Electrical Engineering from Makerere University in 2010 and her M.S. and Ph.D. degrees in Electrical Engineering (2014) and Applied Physics (2017) respectively from the University of Michigan. As a postdoctoral researcher in the department of Material Science and Engineering at the University of Michigan, Nancy employed synchrotron X-ray tomography in 4D to study the solidification dynamics of icosahedral quasicrystals in situ from the liquid phase. During her postdoc tenure, she joined the staff at the Michigan Center for Materials Characterization as an Instrument Scientist and officially accepted a full-time role with the facility in 2019. Nancy is a past recipient of the Schlumberger and AAUW fellowships and a 2020 recipient of the College of Engineering staff excellence award.

Additive manufacturing offers the ability to rapidly fabricate prototype geometries and novel components not manufacturable by traditional manufacturing means. However, the potential for cracks or defects presents substantial hazard under real service conditions – a hazard for which the microscopy toolset can help illuminate and lead to mitigation strategies. This talk presents a case study in using advanced microscopy to address difficult AM challenges. Defect prone and traditionally non-weldable materials such as the high-𝛾’ nickel-base (Ni-base) superalloys present a high-risk high reward opportunity for AM techniques such as laser or electron beam fusion powder bed. This is due to the use of these materials in some of the most critical applications and extreme environments such as turbine blades. However, fusion-based metal AM processes are largely similar to welding processes and result in similar material cracking issues during processing. Leveraging characterization techniques spanning computed tomography (CT) to electron microscopy, coupled with computational modeling and in-situ process monitoring on the electron beam melting (EBM) AM printer, the relationship between processing conditions and material structure can be established for producing crack free material. Further, through robust characterization approaches, stochastic defects that form within materials fabricated using optimized processing conditions can be shown ultimately to be deterministic. Ultimately, developing these relationships enabled the demonstration that turbine blades could be fabricated from a non-weldable Ni-base superalloy Inconel 738 and have the material quality and mechanical properties necessary to survive the extreme thermal and rotating conditions of a land based turbine.

Michael's Bio
Dr. Michael Kirka is the Group Leader of the Deposition Science and Technology Group and Senior Research Staff at Oak Ridge National Laboratory (ORNL). His research interests are in the fields of process-structure-properties and high temperature materials for critical and harsh applications. For the past eight years Michael has been a member of the DS&T group and building a team focused on materials for extreme environment processed through additive manufacturing at ORNL’s Manufacturing Demonstration Facility (MDF). In this time, the team that he has formed has been instrumental in developing the process science necessary to enable materials of ever-increasing operational capabilities, which are ever more difficult to process due to defects such as non-weldable nickel-base superalloys and refractory alloys. Michael’s current research focuses on developing and understanding the limitations in the processing science for high temperature materials such as nickel-base (Ni-base) superalloys and refractory metals for additive manufacturing processes through understanding their microstructural evolution and resultant process-structure-property relationships. Michael has further focused on understanding the long-term mechanical behavior and degradation mechanisms in AM materials similar to those observed during service. Program successes of the team include the fabrication, certification and qualification, and engine demonstration of the first full set of AM fabricated airfoils for a land-based turbine engine, developing the processing science for materials in polycrystalline, columnar, and single crystal textures through AM for increased materials performance, and demonstration of processing of defect free molybdenum for thermal propulsion system core applications. Michael joined ORNL in 2014 as a post-doctoral fellow. Michael earned his B.S. in materials science and engineering in 2007 from The University of Michigan, and M.S. and Ph.D. degrees from The Georgia Institute of Technology in mechanical engineering in 2010 and 2014. In 2021 Michael was recipient of TMS’ Young Innovator for Additive Manufacturing Research Award.

New materials and technological advances are being developed at rates faster than ever before, enabled by the emergence of new microscopy techniques, such as fs-laser integrated with FIB-SEM, artificial intelligence in microscopy workflows, image-based simulation, and correlative microscopy. Faster insights are being enabled across diverse materials science applications, including battery characterization, semiconductor failure analysis, and structural analysis of metals and alloys. Part 1 of this talk will showcase the newest capabilities of ZEISS Crossbeams and a variety of application examples across different research and industry segments, including those benefitting from new and emerging correlated microscopy workflows.

Part 2 will specifically consider strategies for 3D FIB tomography data acquisition to enable accurate materials simulation. For this application, acquiring image data that can feed simulations and reproduce real material properties is challenging and relies on satisfying several conditions. For example, the volume must be representative of the “bulk” material microstructure. The (2D) image resolution must capture the relevant scope of material features, and the 3D image must accurately represent the material in all 3 dimensions and at appropriate length scales. We present here a review of the factors and experimental recommendations for best employing FIB tomo for such data collection, using a lithium-ion battery cathode as a test case to demonstrate the approach.

Steve's Bio
Stephen Kelly is the Market Sector Manager for Energy Materials at Carl Zeiss RMS. He has been working in the battery and energy materials space for over 20 years and has extensive experience with materials characterization and fabrication across the energy space. His expertise covers batteries, fuel cells, hydrogen storage materials, and photovoltaics, among others. After receiving his BS in Engineering Physics from Colorado School of Mines in 2002, he went on to receive his Ph.D. in Materials Science and Engineering from Stanford University in 2009. He spent 4 years working as a postdoc at Lawrence Berkeley National Laboratory specializing in x-ray microscopy of solar cells and atmospheric aerosols. He has been working at Carl Zeiss RMS for the last 7 years as an imaging specialist and Sector Manager for the Energy Materials market. He lives in San Francisco, California.

Cheryl's Bio
Cheryl is the product marketing manager for Crossbeam in materials research and electronics (MRE) industries in North America. She received her MA and BS in Microbiology from UT Southwestern Medical Center, and Texas A&M, respectively. She has >25 years of electron microscopy experience across life science, materials science and semiconductors. She was elected Senior Member Technical Staff at Texas Instruments, is a Fellow of ASM, and co-founded Omniprobe to transform the world of TEM sample preparation. She has 15 patents and authored >70 papers including 3 best presentation awards. She received the 2020 EDFAS President’s Award for exceptional service to the Electronic Device Failure Analysis Society.