Effects of processing parameters for vacuum‐bag‐only method on void content and mechanical properties of laminated composites

Abstract

Process parameters for vacuum‐bag‐only (VBO) method are of critical importance to control manufacturing‐induced void content and mechanical properties of laminated composites. Currently, no comparative studies are readily available on various VBO processing parameters namely bagging techniques, cure cycles, and laminate thicknesses on induced defects and mechanical properties. Hence, this study investigates the effects of these parameters on manufacturing‐induced void content and mechanical properties of composite laminates. Laminate samples were manufactured using L27 Taguchi orthogonal array experimental plan. Void contents, tensile and flexural properties of these samples were evaluated. Double VBO technique and direct (modified) cure cycle were found to be the most promising parameters in achieving the lowest void content among choices of bagging techniques and cure cycles, respectively. However, improved mechanical properties were achieved using a single VBO technique due to the higher fiber reinforcement volume fraction. In comparison to a typical cure cycle, the modified cure cycles were able to reduce surface porosity and through‐thickness void by 48.33% and 23.7%, respectively, whereas the tensile and flexural properties were increased by 2% to 3% and 17% to 20%, respectively. In addition, no significant interaction between parameters was observed.

Thermal cycling of strained nickel‐coated glass‐epoxy composite laminates: Effects on macro mechanical and fiber‐matrix interface properties

“…Moreover, the burn‐off method yielded more consistent V f results for all laminate types, and also in general greater consistency with the measured material densities (i.e., higher V f corresponded to higher material densities). The average void content of unconditioned [0°] 16 laminates was 2.84%; this level is consistent with values obtained by Chu et al [ 62 ] and the trend found by Mujahid et al [ 63 ] for high V f laminates. The average thickness of conditioned in‐plane shear specimens was slightly lower than unconditioned specimens.…”

Vibrational analysis of glass/ramie fiber reinforced hybrid polymer composite

“…After that, the nylon peel ply and breather cloth are placed one over the other. [ 54 ] Then it shifted to a thin polymer film attached to a vacuum pump. After that, the bag has fully sealed using a sealant tape.…”

Effect on Compression Molding Parameters in Mechanical Properties of MWCNT/Glass Fiber/Epoxy Composites

“…An increase in compressive strength and reduced shrinkage was achieved by using MWCNTs as nanoreinforcements in hybrid epoxy composites (MWCNT/silica fume cement). The compressive properties of hybrid polymer composites are also improved when MWCNTs are included [29]. Furthermore, it is necessary to do further research into the mechanical and tribological properties of carbon nanotubebased hybrid composite materials.…”