808 クロスプライCFRP積層板の繰り返し温度変動下の非主軸クリープ変形挙動(OS8-(2),OS8 オーガナイズドセッション《複合材料の変形と破壊およびマルチスケール計算技術》)

Abstract

The effect of cyclic heating on the off-axis creep deformation of cross-ply CFRP laminate under a constant stress has been examined. Cyclic heating creep tests, in which a specimen is subjected to cyclic change in temperature between 40℃ and 70℃ under a constant stress, are performed for different fiber orientations (θ = 0°, 15°, and 45°) at different constant values of applied stress (40%, 50% and 60%UTS at 70℃). The experimental results from the cyclic heating creep tests are compared with those from the constant temperature creep tests (40℃, 55℃, and 70℃) to observe the effect of cyclic change in temperature on constant stress creep behavior. For θ = 15° and 45°, the off-axis creep strain under a constant stress with cyclic heating becomes larger than that under a constant stress at constant temperature. It is suggested that the creep behavior is affected by the instantaneous plastic strain that develops during the initial temperature rise under a constant stress. The strain fluctuation with temperature is found to be comparable to that of thermal strain with the change in temperature.