Mechanical properties and morphological characteristics of ARALL reinforced with TRGO doped epoxy resin

Resumo

Mechanical properties in tension, bending, fatigue and lap-shear in two different proportions (0.5%wt and
1%wt) of TRGO (Thermally Reduced Graphite Oxide) doped ARALL (Aramid Aluminium Laminate) were
examined. The materials and their failure modes were characterized morphologically by examination through
SEM (Scanning Electron Microscopy). Some mechanical properties of ARALL were improved when doped
with 0.5% of TRGO, showing a significant increase of fatigue properties, as well as a change in fracture surface
morphology. Tension and bending properties showed variable results and further studies should be carried
out to arrive to definitive conclusions, while lap-shear testing showed lower shear values. The results
were statistically validated through mono-factorial variance analysis. Comparing the present results with previous
work on CNT (Carbon Nanotubes) doped ARALL, it can be stated that: (a) TRGO doped ARALL
showed improved fatigue properties when compared with non-doped ARALL, but in a less effective way
than doping with CNT, (b) TRGO doped ARALL tension properties showed no significant variation as compared
with ARALL alone, showing no deleterious influence as in the CNT doping case, (c) TRGO doped
ARALL bending properties resulted better than non-doped ARALL, but similar than those obtained when
doping with CNT and (d) TRGO decreased the adherence between aramid fiber impregnated L20 epoxy resin
and aluminium. These last results are sustained based on observed improvements as a percentage value,
without a statistical variance analysis made on CNT doped ARALL.
Keywords: Thermally Reduced Graphite Oxide (TRGO), Al 2024, Fatigue, Tension, Bending.