New publication on the role of different void removal mechanisms in VBO processing of advanced thermoplastic composites

Check the latest publication of Jagadeesh Swamy of an experimental study on the role of different void removal mechanisms in vacuum-bag-only (VBO) processing of advanced thermoplastic composites.

The current study is focused on understanding the role of different void removal mechanisms in VBO processing of advanced thermoplastic composites. For this purpose, two commercially available Carbon/Poly-Ether-Ketone-Ketone (C/PEKK) tape materials were evaluated, distinct in morphologies, such as surface roughness and fiber-matrix distribution, and physical characteristics.

The VBO consolidation results proved that the void reduction and removal mechanisms varied depending on the tape material. Depending on the tape material, a significant difference in the consolidation dwell time was observed to achieve <1% void content parts, which indicates that despite the tapes having the same polymer type matrix, they differ in their diffusion behavior.

Two causes for the difference in the times required for consolidation have been pinpointed. Firstly, the diffusion coefficients may be different for the two tapes. Although the matrix material in both tapes is PEKK, the exact formulation is unknown. Secondly, the volume of gases, which comprises entrapped air and the volatiles that evaporate during the process, may be different.

Jagadeesh has performed this research at the TPRC in close cooperation with the Production Technology research group of Remko Akkerman from the University of Twente.