Hydrogen induced strain localization in Al-Zn-Mg-Cu aluminum alloys

It has been well documented that solute hydrogen atoms increase the mobility of dislocations in metals and alloys, thus promoting highly localized deformation which eventually leads to the rupture of a material. However, little is known about the mechanism of hydrogen-enhanced dislocation mobility that influences the macroscopic fracture process. In this paper, the high resolution X-ray tomography is used to clarify the influence of hydrogen on the initiation and propagation of quasi cleavage fracture in Al-Zn-Mg-Cu alloys. The initiation and propagation of the quasi cleavage crack are discussed by measuring 3D strain distribution ahead of a crack tip in terms of hydrogen embrittlement models.