Evolution Behavior of Hydrogen-Induced Nano Voids in Al–Zn–Mg–Cu Aluminum Alloys under Loading

抄録

Synchrotron X-ray nanotomography, which offers a state-of-the-art resolution, has been applied for the 3D observations of hydrogen induced nano voids under different strain levels in Al–Zn–Mg–Cu aluminum alloys. A great number of nano voids are initiated uniformly across the whole specimen during a loading process. The average diameter and number density of initiated nano voids is 300 nm and 5 × 10¹⁵ m⁻³, respectively. No evidence has been observed that the formation of nano voids results in the propagation of hydrogen induced quasi-cleavage cracks and premature fracture of Al–Zn–Mg–Cu aluminum alloys. Since nano void is one of the hydrogen trap sites in Al–Zn–Mg–Cu aluminum alloys, the majority of hydrogen can be repartitioned to nano voids during deformation due to their high density.