Mg-xAl-Zn(x = 3,6,9)合金腐蚀行为比较研究.

The corrosion performance of AZ series magnesium alloys (AZ31, AZ61 and AZ91) with different Al content in 3.5% NaCl solution is compared in order to find suitable corrosion-resistant materials. The microstructure is characterized by scanning electron microscope (SEM) and X-ray diffractometer (XRD). In 3.5% NaCl solution, its corrosion resistance is tested by polarization curve, electrochemical impedance spectroscopy (EIS) and immersion experiment. The results show that the corrosion behavior of AZ series magnesium alloys is pitting corrosion first and then surface corrosion. The polarization resistance (RP) of AZ61 is as high as 288.88 fl • cm2, the corrosion current density is as low as 0.0026 mA/cm2, and the average corrosion rate is 2.86X 10-4 g/(h • cm2). AZ61 has better corrosion resistance. As the Al content increases, the corrosion resistance of magnesium alloys first increases and then decreases. The increase in corrosion resistance is attributed to the coarsening and continuity of the |3-Mgi7Ali2phase. [ABSTRACT FROM AUTHOR]