Resin-Rich Volumes (RRV) and the Performance of Fibre-Reinforced Composites: A Review

Abstract

This review considers the influence of resin-rich volumes (RRV) on the static and dynamic mechanical and physical behaviour of fibre-reinforced composites. The formation, shape and size, and measurement of RRV in composites, depending upon different fabric architectures and manufacturing processes, is discussed. The majority of studies show a negative effect of RRV on the mechanical behaviour of composite materials. The main factors that cause RRV are (a) the clustering of fibres as bundles in textiles, (b) the stacking sequence, (c) the consolidation characteristics of the reinforcement, (d) the resin flow characteristics as a function of temperature, and (e) the composite manufacturing process and cure cycle. RRV are stress concentrations that lead to a disproportionate decrease in composite strength. Those who are considering moving from autoclave consolidation to out-of-autoclave (OOA) processes should be cautious of the potential effects of this change.

LCM of thermoset-based fiber reinforced composites for large-scale applications: are process kinetics and structural properties antagonistic?

“…Another potential risk, created by the presence of large resin pockets, is to promote residual stresses or micro-cracks to take place during cure or mostly during cool-down of the part. Overall, these resin rich regions have been consistently documented to negatively affect the performance of FRP, as recently reviewed by Mahmood et al [44], who summarized the role of resin rich regions as location for crack initiation and propagation, as well as their negative effects on static as well as dynamic properties. As a conclusion, they recommend exerting caution when modifying the fiber architecture, and to carefully assess the potential change in structural properties.…”

Developments and Industrial Applications of Basalt Fibre Reinforced Composite Materials

“…Damage in NCF basalt FRC has been observed to initiate within the 90 • sub-plies or at the point of contact between the 0 • UD and 90 • sub-plies or at the resin rich volumes (RRV) [123] present between two corresponding NCF based plies [124,125]. The 0 • and 90 • sub-plies refer to the corresponding sub-sections of a NCF ply.…”

The 100 m Composite Ship?

“…The processes of choice for larger vessels have become resin infusion under flexible tooling (RIFT, also known as SCRIMP™ or VARTM) [6,[65][66][67][68][69][70][71][72][73] for leisure craft, or preimpregnated materials within a vacuum bag for racing vessels. The bagging processes provide some consolidation of the laminate giving higher fibre volume fractions and reduced resin-rich volumes [74] and associated voids [41], and hence better performance, than the open mould methods. Even for medium-sized FRP marine vessels, correct infusion and consolidation across the entirety of the laminate requires significant time, labour and cost, and failure can lead to both financial and environmental ramifications through the wasted time, material, energy and resources.…”