Effects of surface cracks and coating on fracture behaviour of microstructured silica optical fibers

The fracture behavior of microstructured silica optical fibers containing surface cracks in tension was investigated using a simplified 3D analysis. Strengthening caused by the polymer coati ng was considered to be associated with the closure stresses uniformly applied to the crack surfaces, which were generally created by the thermal mismatch between the coating resin and the silica glass. The stress intensity factor of the surface cracks in tension was evaluated with considering the crack configurations and surface coating. The effects of crack configurations and closure stresses on the failure loads were also discussed