Effect of Electrolytic Hydrogen Permeation on Tensile Properties and Fracture Process of 6061-T6 Aluminum Alloy

The effects of current density and hydrogen permeation time on the tensile properties and fracture process of 6061-T6 aluminum alloy were studied by electrolytic hydrogen permeation test. The results showed that hydrogen atoms were adsorbed on the surface oxide layer of 6061-T6 aluminum alloy sample during electrolytic hydrogenation, and these hydrogen atoms could be desorbed at low temperature below 150 ℃. Hydrogen atoms also diffused into the alloy and segregated at dislocations or grain boundaries, resulting in Al lattice distortion. The desorption temperature of these hydrogen atoms was much higher. With the increase of current density and hydrogen permeation time, the depth of hydrogen permeation layer of 6061-T6 aluminum alloy sample increased gradually, the strength and plasticity decreased gradually, and the proportion of quasi-cleavage fracture increased gradually. The plasticity index of 6061-T6 aluminum alloy decreased obviously after electrolytic hydrogenation.