Abstract
The effect of cyclic change in temperature on the off-axis creep deformation of a unidirectional CFRP laminate subjected to a constant stress has been examined for different fiber orientations (θ=30°, 45°, and 90°). Thermal ratcheting tests are carried out in such a way that a specimen is subjected to a constant stress and cyclic change in temperature between 40℃ and 70℃ for each of the different fiber orientations. The comparison between the off-axis thermal ratcheting behavior and the off-axis constant temperature creep behavior shows that the thermal ratcheting strain develops more significantly than the creep strain at the constant temperature equal to the mean level of the temperature cycle, regardless of fiber orientation. This observation suggests that the cyclic change in temperature promotes the accumulation of creep strain in the direction of external stress, regardless of fiber orientation.
