In this work, the effect of dynamic strain aging (DSA) on tensile deformation and cyclic creep is investigated for Al-Mg alloys with three different magnesium contents. The serrated yielding on the stress-strain curves was found for two alloys with Mg content of 0.87% and 3.36% subjected to tensile deformation at room temperature, this phenomenon results from DSA. However, the concentration of solute atoms is too low to form the solute atmosphere for Al-0.09%Mg alloy. There is no influence of DSA on tensile deformation of this alloy and then its stress-strain curve at room temperature becomes continuous and smooth. Strain bursts have been observed for Al-3.36%Mg and Al-0.87%Mg alloys subjected to intermediate-temperature cyclic creep. This kind of strain bursts occurring in a stress and temperature range is different from that discovered in pure copper but seems to show the periodicity of strain bursts. Furthermore, the period of strain bursts is decreased with increasing temperature and cyclic stress. The mechanism of dislocation movement during the strain bursts is analysed, and the theoretical formula on the dependence of the strain burst period τ on both the strain burst amount per period ε_a and the steady state creep rate ε has been deduced, that is, τ = 0.314 ε~(0.82)_a/ε. And the values of theoretical calculation are in good agreement with the experimental results in a wide range of temperature and cyclic stress. However, strain bursts haven't been observed in the range of the temperature of 70 to 280 ℃ and the stresses between 25 MPa and 42 MPa during cyclic creep of Al-0.09%Mg alloy with complete unloading. Moreover, both the cyclic creep and static creep of three alloys have been studied at high temperature. In comparison with that of static creep, the critical stress at which the phenomenon of DSA could occur is very much higher. The transition from cyclic creep retardation to cyclic creep acceleration was found only for two alloys with higher Mg content.
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