|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Magnesium Technology 2018
||Acoustic Emission Study of High Temperature Deformation of Mg-Zn-Y Alloys with LPSO Phase
||Klaudia Horvath, Daria Drozdenko, Kristián Máthis, Gerardo Garcés, Patrik Dobroň
|On-Site Speaker (Planned)
Magnesium alloys with different content of zinc (Zn) and yttrium (Y) were extruded at an extrusion ratio of 18:1 at 350 °C. The alloying elements in both Mg alloys formed a long period stacking ordered (LPSO) phase, which during the extrusion process was elongated along the extrusion direction (ED). The magnesium matrix has bimodal character composed by fine dynamically recrystallized (DRX-ed) grains and initial coarse grains elongated along ED. Compression tests with concurrent acoustic emission (AE) measurements were performed along ED at 200 °C, 300 °C, and 400 °C. The deformation mechanisms and the mechanical properties at 200 °C are very similar to those obtained at ambient temperatures, i.e. in the alloy with low volume fraction of the LPSO phase (<10 %) twinning controls the yielding, while in the alloy with high volume fraction of the LPSO phase (around 35 %) dislocation slip and kink formation are dominant. At 300 °C the reinforcing effect of the LPSO phase is reduced and at 400 °C it is not effective anymore.