Manufacturing and mechanical response of nanocomposite laminates

A newly developed methodology is proposed first to manufacture AS-4/PEEK APC-2 nano-composite laminates. The improvement of mechanical properties of nano-laminates is verified by a series of testings systematically. The achievement of empirical results is highlighted as follows. From tensile tests it is found that the optimal content of nanoparticles (SiO2) is 1% by total wt. The ultimate strength increases about 12.48% and elastic modulus 19.93% in quasi-isotropic nano-laminates. Whilst, the improvement of cross-ply nano-composite laminates is less than that of quasi-isotropic laminates. At elevated temperatures the ultimate strength decreases slightly below 75 °C and the elastic modulus reduces slightly below 125 °C, however, both properties degrade highly at 150 °C (≈Tg) for two layups generally. Finally, after the constant stress amplitude tension-tension (T-T) cyclic testing, it is found that both the stress-cycles (S-N) curves are very close below 104 cycles for cross-ply laminates w/wo nanoparticles, and the S-N curve of nano-laminates slightly bent down after 105 cycles. Whilst in quasi-isotropic laminates, the S-N curve of nano-laminates is always slightly below that of APC-2 laminates through the life.