The removal of inter-ply air is critical for limiting porosity in laminates. In this study, an in situ monitoring technique was employed to observe inter-ply air evolution during vacuum bag-only cure. Observations showed that reduced vacuum resulted in inefficient inter-ply air evacuation, a more rapid bubble expansion rate, and formation of new air bubbles. A modified tow impregnation model showed that resin infiltration was impeded at reduced vacuum conditions due to the presence of intra-tow air. However, the cured laminates showed that tows were fully impregnated in all cases, indicating that the entrapped intra-tow air migrated to inter-ply regions during cure. The interactions between intra-tow and inter-tow air at deficient vacuum conditions were revealed. Findings led to the conclusion that air remaining in intra-tow regions contributed more to the increase of inter-ply voids than the reduction in consolidation pressure difference associated with

中文翻译：

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机织预浸料真空袋固化过程中层间空隙形成的机制

去除层间空气对于限制层压板的孔隙率至关重要。在这项研究中，采用原位监测技术观察仅真空袋固化过程中的层间空气演变。观察表明，真空度降低会导致层间空气排空效率低下，气泡膨胀速度更快，并形成新气泡。改进的丝束浸渍模型表明，由于丝束内空气的存在，树脂渗透在降低的真空条件下受到阻碍。然而，固化的层压板显示在所有情况下丝束都完全浸渍，表明在固化过程中截留的丝束内空气迁移到层间区域。揭示了在缺乏真空条件下丝束内和丝束间空气之间的相互作用。