Laser Polishing of Silica Rods

Abstract

Lasers have been widely used in surface modification. In this research a CO2 continuous wave laser has been used to polish the.slot surface of the silica rods. The strong absorption of the lO.6 JlmC02 radiation by the silica surface promotes the softening of a very thin layer of material that flows under the action ofsurface tension. As a result, a mirror smooth glassy surface has been formed which decreases the surface roughness without any substantial change in the surface geometries. The effect oflaser to surface inclination angle on the requisite power requirement was assessed experimentally and theoretically. With laser beam scanning controlled by a computeraided design (CAD) database without specific tooling or human intervention, reliability and reproducibility ofthis process have been greatly improved compared to conventional fire polishing. The p.o~ential use oflaser polishing as a post-processing step for freeform-fabricated parts is very promIsIng.