低能量衝擊損傷及熱循環損傷對船用Gr/PEEK積層板的疲勞壽命影響之研究

Study on The Effects of The Low-Energy Impact And Thermal Cycling Damage on Fatigue Life of Gr/PEEK Laminates Used in Ship

本文經由實驗的方法，探討Gr/PEEK積層板遭受30%Ei（初始能量值）的低能量衝擊、熱循環作用，以及這兩者損傷合成的作用下，對於靜態強度及拉伸疲勞的影響。同時對不同損傷型態材料進行熱壓修補，觀察材料的殘留強度與疲勞性質是否有所提昇與改善，並以電子顯微鏡來探討積層板的微觀的破壞模式。在本文中使用熱壓修補條件為壓力800psi，時間5分鐘，溫度為250度。由實驗中可觀察到衝擊損傷與熱循環損傷對於疲勞壽命有明顯變差的效應。而熱壓修補對單純衝擊損傷或者熱循環損傷具有修補效果。但對具有衝擊後熱循環的狀況則無壽命提升效應。

By experimental observation, the effects of low-energy impact damage，thermal cycling damage and the low-energy impact added thermal cycling damage on ultimate strength and fatigue life were investigated, respectively, for the aquasi-isotropic Gr/PEEK laminate in this study. Furthermore, the results of the improvement of the fatigue life for various damaged specimens that have been repaired by thermoforming method were presented. At the same time, the failure surfaces of various damaged specimens after fatigue tests are examined by S.E.M. Obviously, due to low-energy impact damage or thermal cycling damage, the fatigue life has been detrimental and the fatigue life can be improved by the thermoforming method. Unfortunately, the repaired method is not beneficial for low energy-impact added thermal cycling damage.