Identification of Ni-YSZ anode creep property using PSO for multiscale simulation

Our group has attempted to construct an SOFC multiscale model which can simulate inelastic deformation under operating conditions. In this study, we have focused on mechanical properties of Ni-YSZ anode and aimed to identify creep parameter which is a key factor of inelastic deformation. Measurements were performed at elevated temperatures under controlled oxygen partial pressures using in-situ mechanical testing equipment. Creep parameters of Ni-YSZ anode were optimized to have least difference between the result of numerical material test and experiment, using Particle Swarm Optimization (PSO) algorithm of the approximate optimization techniques based on behavior of self-organized system. As a result, we could confirm transit creep on Ni-YSZ cermet, and identify parameters of it. Simulated creep curves showed good fitting to experimental curves at applied stress up to 5MPa, but deviated at higher applied stresses.