Effect of Ni as a minority alloying element on the corrosion behavior in Al-Cu-Mg-(Ni) metallic glasses

The role of Ni in pitting corrosion in a NaCl solution was investigated by comparing near-eutectic amorphous Al-Cu-Mg alloys with and without Ni. The pitting resistance was enhanced significantly by a small Ni addition in both the amorphous and devitrified states. The minority Ni alloying element is beneficial to pitting resistance in addition to enhancing structural and chemical homogeneity by promoting glass formability. Ni is argued to be superior to Cu for improving the pitting resistance of Al.