Bonding interface zone of Mg-Gd-Y/Mg-Zn-Gd laminated composite fabricated by equal channel angular extrusion
(1. State Key Laboratory for Corrosion and Protection, Institute of Metal Research,
Chinese Academy of Sciences, Shenyang 110016, China;
2. Graduate School of Chinese Academy of Sciences, Beijing 100049, China)
Chinese Academy of Sciences, Shenyang 110016, China;
2. Graduate School of Chinese Academy of Sciences, Beijing 100049, China)
Abstract: In order to improve the mechanical properties and corrosion resistance of Mg alloys, the equal channel angular extrusion (ECAE) was employed to fabricate the Mg-5Gd-5Y/Mg-2Zn-1Gd (GW55/ZG21) laminated composites. After fabrication and annealing treatment, the microstructural evolution, phase constitution, microhardness, and bonding strength were investigated on the bonding interface zone of GW55/ZG21 laminated composites. The bonding interface zone of GW55/ZG21 laminated composites comprises a lot of Mg3(Y, Gd)2Zn3 particles along the bonding interface, some rod Mg24(Y, Gd)5 phases on GW55 side, and a precipitation free zone (PFZ) on ZG21 side. After annealing treatment, Mg3(Y, Gd)2Zn3 particles along the bonding interface increase, rod Mg24(Y, Gd)5 phases on GW55 side decrease, and PFZ is broadened. Meanwhile, the hardness on the bonding interface zone decreases and the bonding strength increases from 126 MPa to 162 MPa.
Key words: magnesium alloys; laminated composite; equal channel angular extrusion; bonding interface; bonding strength