Study on the Corrosion Behavior of Ti-Based Metallic Glass Composites in NaCl Solution

To elucidate the corrosion behavior of Ti-based metallic glass composites in chloride-containing environments, this study investigates the corrosion resistance of an in situ dendritic Ti48Zr20Nb12Cu5Be15 metallic glass composite across varying NaCl concentrations and temperatures. The microstructure, surface film composition, and corrosion characteristics were characterized using XRD, SEM, TEM, EDS, XPS, and electrochemical measurements. Results indicate that the alloy consists of a β-Ti(Zr, Nb) dendritic phase embedded in an amorphous matrix. Both increasing NaCl concentration and rising temperature lead to an increase in corrosion current density and a reduction in the capacitive loop radius, signaling a decline in corrosion resistance. The degradation is primarily characterized by localized corrosion and the selective dissolution of the amorphous matrix, which leaves the dendritic phase increasingly prominent. Following polarization, a multi-component oxide film, dominated by TiO2, ZrO2, and Nb2O5, develops as a protective layer on the alloy surface. However, higher Cl− concentrations and temperatures destabilize this passive film, accelerating matrix dissolution and compromising the material’s overall protective performance.