Tensile Properties of Optical Fiber Irradiated by Low Voltage Electron Beam Homogeneously

Abstract

Homogeneous low voltage electron beam irradiation (HLEBI) with small dose of 0.30 to 1.17 MGy enhanced the elasticity indicated by the initial and maximum slope values of stress–strain curves ((dσ/dε)_i and (dσ/dε)_max) of 250 µm diameter optical fiber (OF), which was constructed with both core (10 µm diameter) and clad (125 µm diameter) silica glasses covered with acryl-urethane sheath (62.5 µm thickness). The highest (dσ/dε)_i and (dσ/dε)_max values of 5.3 and 5.9 GPa, which were about 10 and 20% higher than those (4.8 and 4.9 GPa) before irradiation, were found at 0.104 MGy, respectively. Moreover, remarkable effects of HLEBI of 0.65 MGy on both tensile strength (σ_f) and fracture strain (ε_f) of OF were obtained at each fracture probability (P_f) value. Since HLEBI also enhanced the density of dangling bonds of each material of OF, effects of compressive stress on pull-out resistance and elasticity enhancements of fiber and sheath probably occurred. Thus, 0.64 MGy-HLEBI enhanced the (dσ/dε)_i and (dσ/dε)_max as well as ε_f, resulting in enhancement of σ_f of OF.