Mechanical performance of Nano‐Al₂O₃‐modified composites at cryogenic and room temperatures

Mechanical properties of fiber‐reinforced plastic composites at room temperature can be enhanced by adding nanoparticles. However, the damage mechanisms of nanocomposites at low temperatures are still not understood. In this article, different contents of nano‐Al₂O₃ particles were added on fiber surface by solid–liquid separation method, and vacuum‐assisted resin injection was adopted to manufacture composites laminates. A comparative study on the mechanical behavior of nano‐Al₂O₃‐filled composite at room and low temperatures was presented. Effect of nano‐Al₂O₃ particle contents (0, 0.5, 1, and 2 wt%) on the mechanical properties of glass fiber‐reinforced vinyl ester resin (GF/vinyl ester) composite laminates at different temperatures was investigated. The damage mechanism of these composite laminates in various environments was studied. The results showed that to a certain extent, nanoparticles could improve the mechanical properties of composites at 25 and −60°C. With assistance of scanning electron microscope (SEM) observation, the damage mechanisms of the composite laminates in various temperature conditions were further analyzed. POLYM. COMPOS., 39:3006–3012, 2018. © 2017 Society of Plastics Engineers