Critical role of dynamic precipitation on enhanced creep resistance in Mg–Zn alloy by Mn substitution for Zr

• DOI: 10.1016/j.jmrt.2023.05.130
• Publication Date: 2023-05-18T06:57:05Z
• Authors: Liping Zhong; Liangliang Wang; Yuchen Dou; Yongjian Wang
• Keywords: Dynamic Recrystallization; Recrystallization (geology)

Mg alloys with excellent creep resistance are able to withstand fatigue and damage under high temperature complex load. Adding alloying elements rather than rare earth elements, such as Mn, can further reduce the cost thus facilities widespread applications of alloys. In this paper, individual effect Mn Zr on dynamic microstructural evolution Mg–Zn during is evaluated, basis identical initial microstructure before creep. And essential origin substitution for improving by one order magnitude revealed. Experimental investigations first principle calculations reveal that prior-precipitation α-Mn particles serve heterogeneous nucleation sites precipitation β1′ phases, partitioning in MgZn2 phases promote thermal stability precipitates High number density fine effectively inhibit occurrence continuous dynamical recrystallization (CDRX), pin dislocations impede activation cross-slip, which main reasons enhanced ZM60 alloy. As does not participate formation ZK60 alloy, low prone growth coarsening long-term Large CDRXed grains sparse coarse alloy cannot dislocation movement, contributes cross-slip deteriorate resistance. This work provides new insights designing fabricating outstanding heat-resistance