Effect of molybdenum, manganese and tungsten contents on the corrosion behavior and hardness of iron-based metallic glasses

The effects of molybdenum (Mo), manganese (Mn) and tungsten (W) on the corrosion behavior and hardness of iron-based metallic glasses (MG) were investigated by using electrochemical measurements, X-ray photoelectron spectroscopy, and micro-hardness tester. The results showed that the alloying elements (Mo, Mn, and W) have great influence on the corrosion behavior and hardness. Corrosion resistance of the MG increased with Mo and W content to a critical value (9.4 and 3.2 at%, respectively) and then decreased, while kept increasing with Mn. The corrosion behavior is dependent on the composition of the passive film. The protective Mo(IV), Mn(IV), and W(VI) oxide film on the surface attributes to the enhanced stability of the film. The hardness of the MG is not sensitive to the Mn content, but increased with the Mo and W content. Little influence on the hardness is found when the Mo content is higher than 9.4 at%. Based on the above mentioned influence of alloying elements, corrosion, and wear resistance can be balanced to meet the service of marine pump that served in both corrosive and erosive environments.