Modeling room temperature creep behavior in commercial aluminum alloys
The room temperature (RT) creep behavior of four common commercial aluminum alloys were investigated in order to determine the alloy that exhibited maximum creep. The objective of this paper was to experimentally study the RT creep behavior and develop finite element (FE) model for that alloy. The modified and generalized time-hardening creep equations were used to model the RT creep in Al 7075-T6, which showed the greatest room temperature creep from the four alloys studied. To generate creep parameters for the FE model, these creep equations were fit to RT creep data. This data was calculated using an elastic-plastic (EP) creep approach from tests performed on dog bone specimens at various applied loads. The generalized time hardening creep equation was found to be most suitable to model the room temperature creep behavior in Al 7075-T6. The RT creep behavior for Al 7075-T6 was then modeled by a FE simulation using the generated best-fit parameters. The results suggested that the FE model slightly under predicted the RT creep strain at higher stress and slightly over predicted the RT creep strain at lower stresses, compared to the EP creep approach. However, the general trends for the FE model and EP creep approach were very similar.