In this presentation, we will cover some of the latest work in advanced and custom additive manufacturing processes for the fabrication of architected and functional materials. The concept of architected materials revolves around the notion that material properties are traditionally governed by the chemical composition and spatial arrangement of constituent elements at multiple length-scales. This usually limits material properties with respect to each other creating trade-offs when selecting materials for specific applications. For example, strength and density are inherently linked so that, in general, the more dense the material, the stronger it is in bulk form. We will review the latest in design methods such as topology optimization, as well as advanced additive micro- and nanomanufacturing techniques to create new material systems with previously unachievable property combinations. These processes include projection microstereolithography (PuSL), direct ink writing (DIW), and electrophoretic deposition (EPD) as well as new advanced concepts such as volumetric additive manufacturing (VAM), computed axial lithography (CAL), parallel two-photon polymerization, liquid metal jetting, and diode-based additive manufacturing of metals (DiAM). The performance of the resulting material constructs is fundamentally controlled by geometry at multiple length-scales, from the nano- to the macroscale, rather than chemical composition alone. We have fabricated materials systems with these features and will review the resulting properties of these mechanical metamaterials in polymers, metals, ceramics, and combinations thereof. These new processes and concepts can also be applied to functional materials such as those for supercapacitor electrodes, optical components, and even for fluidic system such as the recently published cellular fluidics concept.
Biography: Christopher Spadaccini is currently the Materials Engineering Division Leader in the Engineering Directorate at Lawrence Livermore National Laboratory. He has been working in advanced additive manufacturing process development and architected materials for over 13 years and has over 65 peer-reviewed journal publications, 4 book chapters, more than 100 invited presentations, and over 40 patents awarded or pending.
Spadaccini founded several new fabrication laboratories at LLNL for process development focused on micro and nano-scale features and mixed material printing, as well as scale-up for higher throughput.He was the founding Director of the Center for Engineered Materials and Manufacturing prior to becoming a division leader and co-led efforts to establish the Advanced Manufacturing Laboratory, a new facility in the Livermore Valley Open Campus. He has also been chair of multiple LDRD committees including founding chair of the new LDRD Disruptive Research category. He has been a member of the LLNL technical staff for 17 years.
Spadaccini has also been a lecturer in the Chemical, Materials, and Biomedical Engineering Department at San Jose State University, where he taught graduate courses in heat, mass, and momentum transport. He is currently an adjunct faculty member at the University of California, Davis, in the Chemical Engineering Department.
This seminar is sponsored by the Department of Applied Physics and the Ginzton Laboratory