关键词: 预浸料黏性, 预浸料刚度, 剥离试验, 探针试验, 内聚力模型, 有限元

Abstract: To systematically establish the prepreg peeling model which can characterize the stiffness and tack of the prepreg, a test verification system considering tensile, probe and peeling is constructed. First, the shift cantilever peel device for the prepreg is designed, and the tack and dynamic stiffness of the prepreg with various laying process parameters by the 90° peeling test are measured. A peel simulation model is established. Then, the cohesive zone model is used to quantitatively characterize the tack parameters obtained by the probe test. Next, the orthotropic mechanical parameters of the prepreg are measured by the test, and are input into the peeling model together with the tack parameters obtained from the probe test. Results of simulation of the tack and the stiffness of the prepreg with various process parameters are all in good agreement with the experimental values. The simulation reveals that the phenomenon of off-roller during the peel test will affect the measured value of peeling force; therefore, the phenomenon of off-roller and its mechanism are studied. It was found that the radius of the peel guide roller should be set within 3-7 mm, which can reduce the off-roller degree and improve the accuracy of the peel test. Our research completed systematic determination and characterization of the tack and stiffness of the prepreg, providing some reference for modelling and automatic placement simulation of the prepreg.

Key words: prepreg tack, prepreg stiffness, peel test, probe test, cohesive zones model, finite element method (FEM)