On the stress exponent and the creep mechanism of Al- 5wt% Mg

Examination of breakdown stress in creep by viscous glide in Al–5·5 at.-%Mg solid solution alloy at high stress levels

“…15,24 An examination of the literature on creep of Al-Mg alloys in the solid solution range shows a wide range in reported stress exponents and activation energies. [25][26][27] Studies conducted on Al-5 wt-%Mg alloys have reported a 'two-tiered' stress exponent behaviour, where at low stresses the exponent ranges between 1 and 4, [28][29][30] while at higher stresses it is higher, ranging from 4 to 6. 25,26,[31][32][33] The creep rate controlling process changes from the glide motion (n53, class A solid solution alloys) to the climb motion of dislocations (n55, class M metal type) depending on stress and creep rate.…”