Surface properties on magnesium alloy and corrosion behaviour based high-speed wire electrical discharge machine power tubes

The effect of power tubes on AZ91D magnesium (Mg) alloy was investigated by high-speed wire electrical discharge machine (WEDM-HS). This Letter presented the different surface characteristics and corrosion resistance of the fabricated surface. Chemical composition of the fabricated surface was analysed by energy-dispersive X-ray spectroscopy, and the surface salt water contact angle was also measured in this study. The machined surface evidenced a carbon layer and high hydrophobic property (contact angle between 146° and 150°). The corrosion resistance of the samples machined by the WEDM-HS process was studied in 3.5% NaCl solution through electrochemical impedance spectroscopy. The results have shown that when electrical parameters of the five power tubes were used, the good surface properties of the fabricated surface were obtained with few micropits, and using the higher power tube was helpful to improve the AZ91D corrosion resistance. A handy WEDM-HS technology for treating AZ91D is a useful way to improve the corrosion resistance of the AZ91D Mg alloy.