The influence of void content on the structural flexural performance of unidirectional glass fibre reinforced polypropylene composites

Mode I Strain Energy Release Rate in composite laminates in the presence of voids

“…The results show that while the fibre dominated mechanical properties are not significantly influenced by voids [1,2,3,4], the matrix dominated properties are strongly dependent on their presence. Reduction in interlaminar shear [1,5,6], compressive [7,8], transverse [1,2], bending [1,3,9], fatigue [4,10,11,12] and fracture toughness [13,14,15] properties have been reported.…”

“…The influence of void content on flexural performance of UD glass fibre reinforced polypropylene composites was investigated by Hagstrand et al [9]. Although they used different fibre and matrix with respect to reference [1], they found a decrease in both flexural modulus and bending strength of 20 and 28%, respectively, with a void content of 14%.…”

“…A simple analytical approach, based on beam theory, was presented by Hagstrand [9] to evaluate the flexural modulus. A more complete and complex computational model was proposed by Huang and Talreja [18] who analysed the effects of void geometry on elastic properties of unidirectional laminates.…”

Process Induced Defects in Liquid Molding Processes of Composites

“…Cure induced defects refer to composites' internal flaws formed during curing. All three defect types typically act as sites of potential failure initiation and reduce the load bearing capacity (Anders et al, 2016;Hagstrand et al, 2005;Mukhopadhyay et al, 2015). Therefore, understanding the formation mechanisms of such defects is essential towards developing improved LCM processes.…”

“…Depending on the manufacturing process, other types of defects can prove to be much more difficult to eliminate. LCM processes are associated with a number of specific manufacturing defects such as voids, dry spots, in-and out-of-plane fiber undulations, microcracks and part distortions (Fedulov et al, 2015;Hagstrand et al, 2005;Hamidi and Altan, 2017;Mukhopadhyay et al, 2015;Anders et al, 2016). As depicted in Fig.…”