电解渗氢对6061-T6铝合金拉伸性能和断裂过程的影响

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

通过电解渗氢试验,研究了电流密度与渗氢时间对6061-T6铝合金拉伸性能及断裂过程的影响。结果表明:在电解渗氢过程中,氢原子在6061-T6铝合金试样表面氧化层吸附,这部分氢原子可在150℃以下发生低温脱附;氢原子还向合金内部扩散,在位错或晶界等位置偏聚,导致Al晶格畸变,这部分氢原子的脱附温度要高得多;随着电流密度的增大与渗氢时间的延长,6061-T6铝合金试样渗氢层深度逐渐增大,强度及塑性逐渐降低,准解理断口比例逐渐增大;电解渗氢后6061-T6铝合金的塑性指标下降明显。

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.