Determination of lubricating behavior of resin during the sliding process of unidirectional prepreg

In this paper, the lubrication behavior of resin during the molding process of unidirectional prepreg materials was scrutinized using a custom-made device. The thickness of the resin between prepregs under various conditions was calculated using Inverse Hydrodynamic Lubrication (IHL) theory to elucidate the lubrication mechanism. This calculation was confirmed by examining the surface morphologies of the prepreg and employing Digital Image Correlation (DIC) techniques for validation. Furthermore, the effect of unidirectional fiber orientation on the process of inter-ply sliding was quantitatively analyzed through the combined roughness. The study showed that factors such as sliding velocity, normal pressure, and fiber orientation play a key role in the lubrication mechanism. The lubrication behavior of unidirectional prepreg transformed to mixed lubrication under specific conditions. The results in our study of the lubrication mechanism have significant implications for the refinement of molding process and the enhancement of numerical simulations of unidirectional prepregs.