Glass resistance to radiation–part I: Preliminary investigation of three commercial glass fibers.

The effects of γ‐radiation on properties of three types of commercial alkaline earth aluminosilicate glasses (NJE, NJ1, NJ2) were investigated at 5M Gy dosage, using samples of bulk glass, glass fiber, and fiber reinforced laminate epoxy composite. The radiation‐induced defect generation and structural modifications in the bulk glasses were characterized by UV‐VIS‐NIR, FTIR absorption spectroscopy, respectively. Strong radiation resistance was found in NJ2 composed of high content of glass former such as Si and Al, together with variable Fe and Ce oxide. Mechanical properties of the fiber woven fabric taps and reinforced laminate composites were investigated before and after the irradiation. While the tap samples showed minor property degradations after the irradiation, all composite samples degraded by greater than 19% in tensile strength and greater than 55% in interlaminate shear strength (ILSS) at 5M Gy dose level. Deterioration of the composite mechanical properties is primarily attributed to the radiation damage to the epoxy resin and in turn, the failure mode of the irradiated composite samples is dominated by delamination at the interfaces between the fiber glass tapes and the resin under the applied tensile load or shear as compared with the failure mode of fiber breakages for their counterparts without γ‐irradiation. [ABSTRACT FROM AUTHOR]