Investigating the corrosion behavior of rolled and post-short-annealed AXM1021 magnesium alloy

This work aims to examine the corrosion behavior of rolled and post-short-annealed AXM1021 Mg alloy using immersion and electrochemical techniques in a 3.5% Sodium chloride (NaCl) solution. The sliced squeeze-cast AXM1021 Mg alloy billets were used to the rolling process in two different processing temperatures 200° C (200 R) and 300° C (300 R). Followed by the post-short-annealing process conducted at 450° C (200RSA and 300 RSA) for 15 min. The standard mirror polished AXM1021 Mg alloy samples were utilized for the corrosion analysis. The obtained corrosion results are affirmed with the refined grain size, secondary precipitates, and the crystal orientations. It indicates that the 300 R exhibits superior corrosion resistance of 3.345 ± 0.01 mm/yr, and polarization resistance of 525.30 Ω.cm 2 than the others (200 R, 200RSA, and 300 RSA). especially 300R was improved 34.4 % as compared to 200 R corrosion resistance. This is mainly achieved by the homogeneous microstructure and lower dislocation density. Also, the Al 8 Mn 5 cathodic intermetallic particles undergo the corrosion process through micro galvanic coupling. In addition, the strong basal plane {0001} exhibits better corrosion resistance than the {1010} & {1120} non-basal planes, even though it contains refined grains in the 200 R AXM1021 Mg alloy.