Mechanical and impact characterisation of hybrid composite laminates based on flax, hemp, basalt and glass fibers produced by vacuum infusion

This work concerns the production by vacuum infusion and the comparison of the properties of different hybrid composite laminates, based on glass, flax and hemp fibers in different combinations, keeping constant basalt laminates as the inner core of the layered material and a 21±1% fibers volume throughout. The laminates have been subjected to tensile, flexural and falling weight impact tests. Mechanical tests show quite limited differences between the three hybrid configurations, a fact which is also suggested by the not large variation in material density obtained. The main differences have been observed dealing with falling weight properties, carried out at energies between 6 and 24 Joules using a half-inch impactor with a mass of 1.25 kg. Here, the hybrid configuration containing together flax and hemp fibers shows some energy dissipation properties with the onset of complex damage modes in the laminate.