Seminar

Multiscale Fatigue Life Prediction Models for Composite Material

Gun Jin Yun(gunjin.yun@snu.ac.kr)

Department of Aerospace Engineering, Seoul National University

Abstract

Fiber-reinforced polymer matrix composite (FRPMC) materials have experienced fast growth in the aerospace industries over the past several decades, reaching out to applications to primary structural members. Due to nano and micro-sized additives and reinforcements in FRPMC materials and various various physical damage mechanisms, advances in the multiscale predictive models and theories validated with experimental data have been increasingly demanded. For example, carbon-fiber reinforced composite materials are subject to various failure behavior such as i) fiber breakage, ii) matrix breakage, and iii) fiber-matrix debonding under repeated loading conditions. Therefore, it is desirable to predict fatigue life by considering various failure modes for composite fatigue failure. Since conventional failure criteria such as Hasin, Tsai-wu, etc. evaluate failure with stress components from lamina level, failure modes should be evaluated with stress components from the material level to predict fatigue life more accurately. Following introductions of various existing models, multiscale fatigue life prediction models are proposed to accurately predict life of FRPMC under repeasted cyclic loadings. It is expected to predict fatigue life more accurately by evaluating fatigue damage mechanisms of each failure mode at the material level.