Advanced Optical Glasses for Novel Optical Fibers Kathleen Richardson, Clemenson University Research Goundation, DMR 0807016 The international, multidisciplinary team is approaching the formation of micro- structured infrared fibers from several perspectives blending experimental and computational expertise. Clemson’s Glass Science group has been quantifying the visco-thermal behavior and interaction between chalcogenide glasses and the hot- forming (substrate) materials used in extrusion and fiber drawing. Clemson’s Mechanical Engineering group is conducting Finite Element Analysis (FEA) simulations to understand the impact of turbulence in the viscous flow of glasses during extrusion. Partners at University of Adelaide have conducted extrusion tests to provide experimental verification of the extrusion results obtained through simulation. Findings show complex flow patterns and thermal non-uniformities in the extrusion furnace and dies, and glass-chemistry specific wetting variations (a) Wetting droplets of chalcogenide glass at elevated temperatures on common hot-forming substrate materials (b) The surface profile of a steel substrate showing residual adhered glass (c) Backscattered SEM image of the steel substrate indicating preferential chemical interaction of chalcogenide glass with substrate. 700 μm The overarching goal of this funded effort is to advance the fundamental understanding of the intrinsic limits of advanced optical glasses for use in traditional and novel fiber geometries. Such an advance in this research area will answer critical materials science questions, extending current capabilities to design, process and manufacture advanced glasses into glass fibers, resolve key questions on glass’ intrinsic physical properties and how they can be tailored, enhanced and optimized to allow use in novel fiber structures. (a) (b) (c ) (a) Coupled Eulerian Lagrangian (CEL) extrusion simulation results of a die with a channel containing six holes. (b) The initial stages of extrusion of a solid preform using the Arbitrary Lagrangian-Eulerian (ALE) finite element formulation.. Die swell is evident. (a) (b)