High temperature creep deformation behavior of heat-treated (α + β)-Mg-9Li-4Al-1Zn alloy

In this study, the high temperature uniaxial tensile creep deformation behavior of (α + β)-Mg-9 mass%Li-4 mass%Al-1 mass%Zn (LAZ941) alloy was investigated. The creep strength of the LAZ941 alloy was significantly improved by heat treatment. The creep deformation behavior of the heat-treated LAZ941 alloy was unique. As the results of creep tests, it is found that the stress exponent of LAZ941 was about 3. The activation energies of creep at the early and middle stages of deformation were 114.7 and 84.6 kJ･mol−1, respectively, indicating that the diffusing elements controlling the viscous glide of the dislocation changed during creep deformation. •The creep strength of the LAZ941 alloy is improved by heat treatment.•The time to reach 0.1 creep strain is about 9 times longer due to heat treatment.•The creep deformation behavior of heat-treated LAZ941 alloy is unique.•The activation energy of creep for LAZ941 alloy changes during deformation.