Study on cutting surface stripe and wettability of AZ91D magnesium alloy by WEDM-HS

Low discharge energy was used to machine AZ91D magnesium alloy using reciprocating type high speed wire electrical discharge machining (WEDM-HS). Different microstructures were found on bright and dark stripes. Using water contact angle of the droplet at the magnesium alloy surface evaluated the wettability. Results show that contact angle value of magnesium alloy surface after WEDM-HS was higher than magnesium alloy matrix. There were differences surface microstructures between bright and dark stripes, which is the key reason of hydrophoby. Compared with the bright stripe, the value of contact angle of dark stripe was higher and more stable. On submillimeter groove surface, the value of contact angle was increased to 154.71°. This paper provided the facile and cost-effective process method for support the industrialized fabrications of super-hydrophobic AZ91D surface.