Corrosion Behavior of Fe81Cr19, Fe49Co49V2, and Co72Fe4Mn4Nb4Si2B14 Alloys in Simulated Venusian Environment

This study evaluates the high-temperature stability of soft magnetic materials under expected Venusian surface conditions to inform relevant lander designs. Soft magnetic materials enable motors, actuators, and passive components in the power conversion system. We investigate two common bulk crystalline alloys, Fe81Cr19 and Fe49Co49V2, as well as a metallic glass, Co72Fe4Mn4Nb4Si2B14. Pertinent atmospheric conditions were simulated using the NASA Glenn Extreme Environment Rig (GEER). X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive x-ray spectroscopy (EDS) were performed on exposed samples leading to further understanding of the corrosion behavior of Fe- and Co-based materials in a simulated Venusian atmosphere. Both oxidation and sulfidation are induced in all three materials. The amorphous structure of Co72Fe4Mn4Nb4Si2B14 and, potentially, the formation of B and Si-based protective layers, yield improved corrosion resistance relative to Fe49Co49V2.