Dual-Functional Metallized Basalt Fiber with Exceptional Electromagnetic Interference Shielding and Joule Heating Capabilities under Simulated Lunar Temperature Conditions

The lunar mare region is rich in basaltic minerals, and in situ resource utilization (ISRU) is a fundamental strategy for sustainable extraterrestrial construction. However, combining electroless plating with basalt fibers for such construction leads to a significant mismatch of coefficient of thermal expansion (CTE) between the fiber substrate and metal coating. Under extreme temperature alternations, this mismatch induces interfacial thermal stress concentration, causing coating peeling and performance failure. To address this issue, this study, using commercial terrestrial basalt fiber as an analogue for lunar basaltic materials, proposes an ISRU-inspired metallized fiber composite suitable for wide-temperature-range applications. By sequential electroless nickel plating and copper electroplating on basalt fibers, a nickel-copper-coated basalt fiber fabric (BF@Ni@Cu) was successfully fabricated, exhibiting high electrical conductivity, excellent electromagnetic interference shielding effectiveness (62.59 dB), and significant joule heating performance. The Ni interlayer forms a CTE gradient transition between the basalt substrate and the outer Cu layer, mitigating interfacial thermal stress. After annealing and PDMS encapsulation, the surface reflection characteristics are effectively regulated. To verify reliability under lunar diurnal temperature variations, cold-thermal shock cycle tests simulating the lunar range (from -196 to 130 °C) are conducted. After 30 cycles, the material maintained structural integrity without cracking or peeling, successfully overcoming interfacial thermal stress concentration. Consequently, the EMI shielding and joule heating performance showed only slight degradation, demonstrating excellent temperature shock resistance. This study not only provides a fiber metallization strategy that retains high performance under extreme temperature alternations but also offers a potential technical pathway inspired by ISRU for multifunctional protection and thermal management materials in future lunar base construction, through the design concept of thermal stress alleviation and failure-mode control via a gradient interlayer.