Paulino, Luís Filipe da Costa2026-05-052026-05-052022Paulino, L. F. C. (2022). Effect of radiation-assisted cure on the functional properties of carbon-epoxy composites. Unpublished manuscript.http://hdl.handle.net/10400.26/62992Resumo alargado da dissertação de mestrado com o mesmo título, defendida em 2002.Gamma radiation has been successfully used to improve polymer's properties. In this regard, this study aims to assess if it is possible to improve carbon-epoxy composites' mechanical and thermal properties, with potential application in aeronautics, through controlled exposition to gamma radiation. In addition, make a comparative study between post-cure irradiation and radiation-assisted cure. To accomplish this, the material is subjected to gamma radiation in different stages of the resin's cure. The laminates were fabricated with a 3K carbon mat with 160 g.m-2 and a two-component resin SR8200 with SD7206 hardener through wet-layup. The test specimens were cut from the laminate according to ISO 527-4/2020 and ISO 14125/2011. Finally, they were irradiated according to three irradiation methodologies: post-cure irradiation, irradiation after 2 days, and after 10 days with doses from 4 to 7 kGy. These doses were selected based on a preliminary study. The specimens were tested through tensile and flexural testing, thermogravimetry analysis and differential scanning calorimetry. The results showed that up to 6 kGy, the three irradiation methodologies improved the thermal stability and mechanical properties without affecting molecular structural integrity due to chain-scission, compared to non-irradiated specimens. The biggest increases registered were a 32.36 % increase in Young's modulus and a 51.23 % increase in flexural modulus for irradiation after 2 days, and an increase of 5.10 % in degradation temperature and 7.44 % in glass transition temperature for the same irradiation methodology, suggesting that radiation-assisted cure is more effective at improving the material's properties compared to post-cure irradiation.engRadiation-assisted cureCarbon-epoxyCompositesCrosslinkingMechanical propertiesThermal propertiesCura assistida por radiaçãoCarbono-epóxiCompósitosReticulaçãoPropriedades mecânicasPropriedades térmicasworking paper