An experimental investigation of compaction behavior of carbon non-crimp fabrics for liquid composite molding
| Autor: | Jindong Zhang, Jin Yang, Long Li, Yan Zhao, Yuexin Duan |
|---|---|
| Rok vydání: | 2015 |
| Předmět: | |
| Zdroj: | Journal of Materials Science. 50:2960-2972 |
| ISSN: | 1573-4803 0022-2461 |
| Popis: | Compaction of the preforms to a desired fiber volume fraction in liquid composite molding has a significant influence on the subsequent injection process and mechanical properties of the final composites. Hence, knowledge of the compaction of the fabric preforms is important for improving the composite product quality and developing the mold filling simulation. In this paper, the compaction behavior of four types of carbon non-crimp fabrics (NCFs) was experimentally studied. The investigation of compaction behavior included the influence of number of cyclic compaction, number of layers, stitching pattern, compaction speed, and the lubrication (wet states). The results show that the compaction curves tend to be stable and repeatable with an elastic deformation from the third cycle. Other factors affecting the compaction behavior can be explained by the nesting effect, considering the special structure of the NCFs. Gaps between fiber tows created by the stitches may provide room for the adjacent fibers to embed or nest in. Meanwhile, the relaxation of the preforms after compaction was discussed in terms of the energy dissipation. The results elucidate that the lubrication and compaction speed have no significant effect on the compaction process, but exhibit influence on the relaxation. Finally, the microstructural observation of the laminates backs up the experimental analysis and highlights the deformation of fibers at the tow gaps. The change of the internal parameters, including the shape and dimensions of the tows and the gaps, with the compaction degree was statistically studied. It also provides geometrical parameters for establishing predictive models of carbon NCFs with different compaction degrees. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|