Prediction of long-term durability of unidirectional CFRP

This study examines the applicability of the SFF model (Koyanagi J, Kotani M, Hatta H and Kawada H. A comprehensive model for determining tensile strengths of various unidirectional composites. J Compos Mater 2009; 43: 1901–1914) to the time and temperature dependence of strength for two kinds of CFRP. The only difference in the materials is the reinforcing carbon fiber, which is not time or temperature-dependent; the time and temperature dependence of strength for the two materials differ. The SFF model, however, can follow their strengths well. Postulating the SFF applicability, the validity of the conventional accelerated testing methodology by elevated temperature and a simple method to predict long-term durability, including creep lifetime, are discussed.