A new degradation model with critical antioxidant concentration concept for safety cables

To simulate synergisms in thermal and radiation environments, and to exhibit the effect of antioxidants, we propose a new degradation model with the critical antioxidant concentration concept for safety cables in nuclear power plants. A chemical reaction scheme is used to represent the oxidation reaction via the decomposition of peroxide radicals. The effects of antioxidants are included in this scheme to exhibit the critical concentration phenomena. Diffusion equations are added to their reaction rate equations to allow reproduction of diffusion limited oxidation. Such a degradation model with antioxidant effect is discussed for various degradation behaviors in polymers used for safety cables, and its effectiveness is verified.