Influence of Thermomechanical Treatment on Tension–Compression Yield Asymmetry of Extruded Mg–Zn–Ca Alloy
Thermomechanical treatment consisting of pre-compression and isothermal aging at 150 °C for 16 h was applied to the extruded Mg–Zn–Ca (ZX10) alloy in order to reduce tension–compression yield asymmetry and improve mechanical properties via strengthening mechanism. With respect to the initial texture of the alloy, pre-compression leads to a formation of extension twins. A solute segregation and precipitation along twin boundaries is realized during a subsequent isothermal aging. After thermomechanical treatment, a solute solution and precipitation hardening contribute to the strengthening of the alloy. Active deformation mechanisms were monitored during compression or tension using the acoustic emission technique.
KeywordsMagnesium Pre-compression Twinning Precipitation Acoustic emission
This work received support from the Czech Science Foundation under grant No. 17-21855S; the Grant Agency of the Charles University under grant Nr. 1262217; the Operational Programme Research, Development and Education, The Ministry of Education, Youth and Sports (OP RDE, MEYS) under the Grant CZ.02.1.01/0.0/0.0/16_013/0001794.
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