Physical Modeling of Degradation Failure Mechanism of Rhenium–Tungsten Filaments in Mass Spectrometers of Environmental Control and Life Support System: Electromigration, Thermal Effect, and Coupled Oxidation

In aerospace missions, the proper functioning of the environmental control and life support system (ECLSS) is critical to ensuring mission success. As a key gas detection device in the ECLSS, the performance of the rhenium–tungsten (Re–W) filament in the ion source of quadrupole mass spectrometers directly affects the stability and data accuracy of the instrument. However, tungsten alloy filaments may still suffer damage due to thermal stress, electromigration, mild oxidation, and other factors during operation. Therefore, investigating the damage mechanisms of Re–W filaments is of substantial practical importance. This study aims to explore the failure mechanisms of Re–W filaments and provide a basis for performance improvement in practical applications. The paper systematically introduces the working principle of quadrupole mass spectrometers, details the construction of the experimental platform, and conducts filament failure experiments under high-temperature electrified conditions in a vacuum environment. Subsequently, scanning electron microscopy and x-ray diffraction were employed to analyze both intact and damaged Re–W filaments, elucidating their failure mechanisms. Experimental results reveal the potential causes of filament damage during failure processes, including electromigration, thermal-stress-induced damage, and oxidation. This study represents the first systematic investigation into the failure mechanisms of Re–W filaments in quadrupole mass spectrometers, offering experimental evidence and technical support for future performance enhancement strategies. These findings contribute to improving the reliability of ECLSSs and the success rate of aerospace missions.