PSI - Issue 34

H. Oberlercher et al. / Procedia Structural Integrity 34 (2021) 111–120

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Hannes Oberlercher/ Structural Integrity Procedia 00 (2019) 000 – 000

3.2

Cross-section observation

3.2.1 MF CFC 3D-printer Typical examples of cross-section images of the MF 3D-printer in the direction perpendicular to the fiber are shown in Figure 4 and Figure 5. The four test runs with different layer heights show a clear irregularity in the microstructure. Sample (a) shows a large content of cavities in the matrix material. With increasing of the consolidation pressure, these cavities are significantly reduced (see Figure 4 (b)-(d)). However, sample (d) shows the lowest percentage of voids but an uneven distribution of the fibers in the matrix.

Figure 4: Single line samples of the MF 3D-printer

Figure 5 shows four-layers of a laminate with the parameters of sample (d). Especially between the individual layers there is a large amount of cavities (See Figure 5 dark spots). The matrix material to the upper layers is only slightly connected to the lower layer.

Layer4

Layer3

Layer2

Layer1

Figure 5: Cross-section of the laminate with 0.105mm

3.2.2 CFC 3D-consolidation-printer Typical examples of cross-section images of the 3DCP in the direction perpendicular to the fiber are shown in Figure