Corrosion and Mechanical Properties of Novel Fe-Based Bulk Amorphous Alloys

Fe70-xNixSi7.5B17.5Nb5(x = 0, 5, 10, 15, 20, 25 at.%), (Fe50Ni20)70-yCrySi7.5B17.5Nb5(y = 3, 6, 9, 12 at.%) and (Fe50Ni20)61Cr9CozSi7.5-zB17.5Nb5(z = 2, 4, 6 at.%) alloys were fabricated by the copper mold suction casting method. Structure, corrosion resistance and mechanical properties of the alloys were investigated. The results show that the bulk amorphous alloy with the Co content of 6 at.% has the highest compressive plastic strain (εp = 1.2%) and ultimate compressive strength (σmax = 4110 MPa) and shows the best corrosion resistance with the low corrosion current density (Icorr = 1.149 × 10–8 A cm−2) in artificial seawater solution compared to the other alloys. This study will provide a new approach for the design of corrosion-resistant Fe-based bulk amorphous alloys with excellent mechanical properties.