Radiation-induced effects on commercial 3D printing materials exposed to high x-ray doses

Abstract Fused filament fabrication is among the most widely used 3D printing techniques, that allows to create complex devices from a continuous filament of a polymeric material. This adaptable technique has garnered considerable interest for the development of components functioning under severe radiation environments, including particle accelerators and nuclear reactors. In this work, we evaluated the radiation effects on several categories of commercial printing materials, namely the poly(lactic acid) (PLA), the acrylonitrile butadiene styrene (ABS), and a thermoplastic elastomer (TPE). Printing filaments have been exposed to x-rays (up to 160 keV) at 0.60 Gy s⁻¹, from 45 kGy to 2 MGy. The results from tensile tests, thermal analyses (differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical thermal analysis), and spectroscopy tests (Fourier transform infrared spectroscopy and Raman analysis) reveal a dose-dependent degradation of material properties, predominantly affecting mechanical properties rather than chemical and thermal ones. The PLA shows the lowest radiation tolerance among the three, dramatically decreasing the tensile strength above 100 kGy, while TPE and ABS reach a comparable mechanical degradation after 1 MGy and 2 MGy, respectively. Radiation-induced effects are investigated, and the degradation is primarily attributed to chain scission as the principal damage mechanism.