10 June 2021

Through the combination of pristine carbon fibres (CFs) with nanomodified resins and sized CFs with unmodified resin, INEGI developed different types of multifunctional and multiscale CFRPs with improved mechanical and electrical performance. In the last period, INEGI received and tested different types of modified CFs that were provided by other SmartFan partners: CANOE supplied sized CFs with different percentages of carbon nanotubes (CNTs) and carbon nanofibres (CNFs), while NTUA prepared electropolymerized CFs. After optimization of the processing conditions, prepreg materials and CFRPs were produced for different mechanical characterization, namely tensile at 0° and interlaminar shear strength (ILSS).

According to the tensile results obtained, the sized CFs did not influence the tensile modulus of the material, while the tensile strength increased 8.5 and 12.8 % for CFs sized with CNTs and CNFs. Regarding the ILSS experiments, the CFRPs produced with CFs from CANOE containing only the sizing solution, without nanoparticles, resulted in an ILSS decrease around 7 %, while the introduction of carbon-based nanoparticle restored and/or increased the interlaminar shear strength of the materials. SEM images of the specimens after ILSS testing can be observed in Figure 1, denoting the affinity between the matrix and the CFs. More interesting results were obtained for the CFRP produced with electropolymerized CF from NTUA, with enhancements around 9 %.

Figure 1

Based on the results achieved throughout the project duration, pre-impregnated materials have been under production in the past months for the preparation of 2 demonstrators (to be manufactured by Dallara): a racing front wing and an energy absorber for the automotive industry.