ChEMS Seminar: Practical Fundamentals of Additive Manufacturing of Ceramics (AKA The Good, the Bad, and the Ugly)

McDonnell Douglas Engineering Auditorium (MDEA)
John W. Halloran
Department of Materials Science and Engineering
University of Michigan 
Ann Arbor, Michigan

Abstract: Additive manufacturing of ceramics is a field that combines an interesting interplay of polymer science, colloids, optics, and manufacturing. I will discuss a number of additive manufacturing methods for ceramics at both for lab-scale prototyping and for industrial production. I will discuss in more detail methods based on photopolymerization of ceramic suspensions, including stereolithography and related methods. Resolution is determined by the patterning light and by the depth and width of the photocured features. These depend upon the energy dose, intensity, photoactive components which determine absorption and scattering and refractive index. The variation of monomer conversion with depth is important for successful curing of multiple layers. The relationship between all of these parameters are presented with simple models, and discussed in terms of the practical fundamentals of this processing method. Lastly, I will discuss recent progress on commercial-scale manufacturing of ceramic cores for investment casting of airfoils.

Biography: John Halloran is the L.H. and F.E. Van Vlack Professor in the Materials Science and Engineering Department at the University of Michigan, Ann Arbor and a Fellow of the American Ceramic Society. After completing his PhD at MIT he served on the faculty of Pennsylvania State University and Case Western Reserve University. Before joining Michigan in 1990, he was with a start up company in the Boston area. He is an Editor-in-Chief for the Journal of the American Ceramic Society and author of over 200 journal publications. He is a co-founder of DDM Systems, Inc. a spin-off from research projects at the University of Michigan and Georgia Tech on direct digital manufacturing for turbine components.

Hosted by: Professor Martha Mecartney