Pr. Griffin et al., THE EFFECT OF MICROSTRUCTURE ON FLOW PROMOTION IN RESIN TRANSFER MOLDING REINFORCEMENT FABRICS, Journal of Microscopy, 177, 1995, pp. 207-217
The resin transfer moulding (RTM) process is becoming increasingly imp
ortant for the manufacture of continuous fibre-reinforced thermosettin
g resin matrix composites, The RTM process is a closed mould technique
which reduces volatile emissions relative to traditional hand lay-up
methods, The fibres, generally as several layers of fabric, are prepar
ed as a preform and laid in the closed mould. The resin is injected, a
t one or more points, and flows through the mould to form the finished
product. In the manufacture of high-performance composite structures,
the now of resin is constrained by the high volume fraction of reinfo
rcement fibres required to achieve the performance, Commercial fabrics
are becoming available which are woven with specially designed mesosc
ale architecture to promote flow of the resin, The flow rates in a ser
ies of such fabrics have been studied. The microstructures of the resu
lting composites have been examined using brightfield optical microsco
py. A Quantimet image analyser was used to quantify the structures on
both the mesoscale and the microscale. The flow rate has been shown to
be related to the presence of both large and more modest sized pore s
pace in the reinforcement architecture.