Thermal Expansion of Sol-Gel SiO₂ Glass Fibers

The thermal expansion of SiO 2 glass fibers synthesized by the sol-gel method was measured in the temperature range of 100 to 300°C using a laser interferometer developed at NRLM. Fibers as grown represent shirinkage of length, but after annealing, thery represent low thermal expansion as is seen in the usual sol-gel SiO 2 glasses. It is believed that the former is in a sintering process and the latter is a true glass.