Control of Track Morphology in Digital Glass Forming

Digital Glass Forming involves locally heating a glass filament using a laser while continuously feeding relative to the workpiece. This enables precise control of the viscosity of the molten region. This viscous melt pool is deformed by forces from the filament and workpiece. This paper investigates the relationships between the input parameters, laser power, feed rate, and scan speed, with the resulting track morphology. Tracks are used to build larger, more complex structures. By underfeeding the filament relative to the able scan speed, the glass is locally drawn to produce tracks with significantly smaller cross-sectional areas than the feedstock material. This technique allows for the production of arbitrary geometries and surface features using a smaller equivalent diameter than the input feedstock. The paper explores the available process zone for this underfed deposition mode and the limitations of this method.