Effects of Lanthanum and Cerium Mixed Rare Earth Metal on Abrasion and Corrosion Resistance of AM60 Magnesium Alloy

The effects of lanthanum and cerium mixed rare earth metal on the abrasion and corrosion resistance of AM60 magnesium alloy were analyzed by the hydrogen evolution method, mass gain test, electrochemical test, as well as friction and wear characteristics test. It can be found that after adding lanthanum and cerium mixed rare earth metal, AM60 magnesium alloy's electrochemical properties, friction and wear performance are all improved in 0.35%NaCl solution. For example, hydrogen evolution corrosion current density, polarization current density and capacitance all decrease while its corrosion potential and polarization resistance increase. Moreover, its friction coefficient and specific wear rate decrease. This is because adding of lanthanum and cerium results in refining of the grains of α phase and Mg17Al12 phase of AM60 magnesium alloy and forming of new Al2Ce and Al11La3 phases, which inhibit the progress of cathodic depolarization, whilst the added Ce and La form a composite anodic film on the surface of the alloy, which block the dissolution and improve the corrosion resistance.