Synergistic regulation of mechanical and damping properties in Mg-Gd-Y-Zn-Mn alloys via extrusion at different temperatures

This study overcomes the pervasive strength-damping trade-off in magnesium alloys via extrusion temperature control and aging of an Mg-8.9Gd-3.9Y-1.3Zn-0.8Mn alloy. ET450 produced a bimodal structure (3.2 μm DRX grains) with 390 MPa UTS, outperforming the fully DRXed ET480 (5.1 μm, 376 MPa). After peak aging of ET450 (ETA450), β'/γ' nanoprecipitates strengthen the alloy to 510 MPa (+30.8% UTS) through dislocation shearing. Crucially, ETA450 retained a high damping capacity (Q -1 =0.018), rivaling the un-aged ET480 (0.021). This strategy of low-temperature extrusion and aging provides a new design pathway for high-performance Mg-RE alloys.