Evolution of the deformation relief on the surface of a clad aluminum alloy at random cyclic loads

The deformation relief was revealed to be formed and evolved on the surface of a cladding layer of a D16AT aluminum alloy under random cyclic loading. The surface saturation, roughness, and microplastic deformation are found to be quantitative estimates of the deformation relief and damage levels. Experimental deformation relief characteristics-load cycle number relations are similar and can be employed for predicting the fatigue crack initiation in aircraft structure elements.