Corrosion Evolution of AZ31 Mg Alloy with a Nano Crystallized Film

Abstract

Abstract A comprehensive investigation of nano crystallized GaN film synthesized on AZ31 magnesium alloy substrate using atomic layer deposition (ALD) is presented in this paper. The microstructure and mechanical analysis indicate the nano crystallized film is homogeneous, well-adhesive to Mg alloy substrate. The corrosion experimental results demonstrate that the nanometer crystallized film turns Mg alloy corrosion process from longitudinal/non-uniform to horizontal/uniform corrosion, which is deduced from the facts that a great but less fluctuation surface potential mapping, a smaller ∆Erev, corr and a more uniformed corroded morphology. A higher Ecorr , a smaller icorr and a higher Z also mean the film can yield a prominent amelioration in the Mg alloy corrosion resistance. The work proposes that a uniform coverage even in a nano-magnitude and crystallized form could make corrosion more uniform and later.