Mechanical properties and manufacturing of TiNi/CFRP smart composites

TiNi/CFRP composites were fabricated by sandwiching TiNi wires between layers of CFRP prepreg by hot-pressing in the temperature range of 150-180°C, by controlling the applied pressure. The microstructural properties of hot-pressed TiNi/CFRP composites were investigated by SEM. The tensile strength of CFRP monolith not embedded with TiNi wires is 1.3GPa, whereas that of TiNi/CFRP composites is about 1.2GPa. The fracture behavior was studied by an AE technique under tensile test, to analyse the fracture process. It was confirmed that the detected AE signals resulted from generation of fibre breakage, interfacial debonding and microcracks in the epoxy matrix. The damage recovery effect of fractured specimens was successfully obtained by heating above 80°C.