Influence of Deposition Temperature and Compaction Force on the Infusion Properties of DFP Preforms

The deposition of dry fiber materials in the dry fiber placement (DFP) process with subsequent impregnation is becoming increasingly widespread. The wing covers of the Irkut MS 21 are already being manufactured using the DFP process, and research projects at major aircraft manufacturers are increasingly incorporating the technology. In this process, the deposition speed depends on the temperature and the compaction force. However, it is not only the laying speed that counts during production, but also the impregnation afterwards. Thus, the effects of the depositing parameters on the infusion properties must be known. In this study, a two-step approach is used. Planar preforms (Hexcel HiTape) that have been deposited with different parameters are divided into four quadrants, and first samples are analyzed for isotropic properties in a two-dimensional infusion test. Then, one-dimensional infusion tests are performed so that infusion times can be compared. The tests show that the lowest infusion time can be obtained at low deposition temperature and high compression force. Additionally, using a comparable material (Solvay TX 1100), it is shown that increasing the gaps between the tows increases the permeability and homogeneity of the preform.