Microstructure, texture, mechanical properties and electromagnetic shielding effectiveness of Mg-Zn-Zr-Ce alloys

The microstructure, dynamic recrystallization, texture, anisotropic behaviour, mechanical properties and electromagnetic shielding effectiveness of Mg-Zn-Zr-Ce alloys were comprehensively investigated in this study. Results indicated that the addition of Ce refined the grains and induced the formation of a Mg-Zn-Ce phase with a unique orthorhombic structure. Dynamic recrystallization was improved when Ce was added because the particle stimulated nucleation mechanism. The random orientation of recrystallization grains weakened the basal texture. The anisotropy index decreased from 1.02 to 0.43 after 1.16 wt% Ce was added. Ce addition enhanced the mechanical properties when the Ce content ranged from 0 to 1.90 wt%, and then decreased with a higher 2.74 wt% Ce content. Electromagnetic shielding effectiveness was also improved initially with the addition of Ce, and then decreased, but was still higher compared with the Ce-free alloy. Good mechanical properties and excellent electromagnetic shielding properties were simultaneously achieved through 1.16 wt% Ce addition. The alloy not only exhibited good yield strength (249 MPa), ultimate tensile strength (316 MPa), and elongation (δ=15%) but also superior electromagnetic shielding effectiveness with 71 dB at 1200 MHz.