Abstract Mechanical properties of composite laminates can be tuned by either tailoring ply orientations or by using ply drops to change thickness profiles. The latter cause resin-rich pockets to form in thermoset composites that are autoclave cured after lay-down. This paper focuses on the morphology of ply drop regions with carbon fibre thermoplastic composites manufactured using in-situ consolidation with laser-assisted tape placement. Our work shows that when laying a 0 deg ply (parallel to the ply drop) over a ply drop then the ply readily conforms to the shape of the ply drop, eliminating voids. However, when a 90 deg ply covers a ply drop, the processing direction affects behaviour. When the ply ascends a ply drop, a void is created. On the other hand, when the ply descends a ply drop, the substrate changes its shape due to combined laser heat and roller pressure, leading to significantly smaller voids.

中文翻译：

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使用激光辅助胶带放置制造的热塑性复合材料中层片的形态

摘要 复合材料层压板的机械性能可以通过调整层片方向或使用层片下降来改变厚度分布来调整。后者导致在热固性复合材料中形成富含树脂的口袋，这些复合材料在铺设后进行高压釜固化。本文重点介绍了使用原位固结和激光辅助胶带放置制造的碳纤维热塑性复合材料的层片下降区域的形态。我们的工作表明，当将 0 度层（平行于层下降）放置在层下降上时，层很容易符合层下降的形状，消除空隙。然而，当 90 度层覆盖层下降时，加工方向会影响行为。当层上升到层下降时，就会产生空隙。另一方面，当帘布层下降时，帘布层下降，