Effects of electron irradiation on fibers prepared from the self-developed Chang’E-5 lunar regolith simulant

Abstract

The design of fiber-reinforced composites is considered as a feasible way to withstand the irradiation environment in lunar base construction, and fibers play an important role as reinforcement materials. In this work, we focused on the fiber spinnability of the self-developed Chang’E-5 lunar regolith simulant (LRS) and the effect of the electron irradiation on the structures and properties of the fiber. The results showed that the surface of the irradiated fibers was smooth and no crystal were formed, but the thermal stability of the fibers was altered, with the fiber S4 irradiated at a moderate fluence of 4 × 10¹⁵ e cm^-2 having the lowest thermal stability. In addition, the tensile strength of the fibers showed a tendency to increase and then decrease, with the fiber S4 giving the highest tensile strength. FTIR, Raman and XPS spectroscopic analyses indicated the same trend of degree of polymerization (DOP) and the bridging oxygen (BO) content with tensile strength. The M$\ddot{o}$ssbauer spectra revealed that the Fe³⁺and Fe²⁺ content in the fibers was changed by electron irradiation, with the S4 fiber exhibiting the highest Fe³⁺ content, resulting in more Fe³⁺ to form [FeO₄] tetrahedra, thus strengthening the network structure.