Published online by Cambridge University Press: 10 February 2011
Median strength 4 GPa and Weibull slope 5 were obtained after stripping the coating from fibers with a mechanical stripping technique. However, the median strength was found to decrease to 1.6 GPa following fusion splicing. Most of the fractures in a tensile test occurred at a distance of 1 mm from the splice point. The internal axial tensile stress in the fiber cladding was found to be removed over a 2 mm section over the splice point. The surface fictive temperature was found to be decreased only at the zones where the fibers fracture. The reason for the fiber weakening during fusion is therefore thought to be due to the intrinsic structural changes in the silica indicated by the fictive temperature decrease. The magnitude of the decrease can be reduced by using a quicker fusion process. The corrosion velocity around a fusion splice point during aging in hot tap water was found to be significantly higher than along the fiber elsewhere. Silica layers with a thickness of hundreds nanometers were removed uniformly. However, the weakest points (roughest surface) after water aging were located in the ends of the recoated section.