File talk:Kelvin deformation 2.png

The image posted says that it is the response under constant stress. This is only correct until the given t. If it was held under constant stress it would reach a maximum asymptote value at infinity. In the image at time t, the stress is removed and strain goes away as depicted.

The correct caption would be that the model is held under constant stress until time t, then stress is removed and the strain experiences decay.