Nanostructure Distribution and Strengthening Mechanisms in the Interface Regions of Al–Zn/Al–Mg Multilayered Composites

Abstract

In this study, we examined the distribution of nanostructures in the interdiffusion layer of AlMg/AlZn/AlMg multilayer composites with different layer width via microbeam small-angle X-ray scattering (SAXS) measurements and direct observation using transmission electron microscopy (TEM). The changes in scattering profiles across the graded interfacial layers reflected the spatial change in the volume fraction, average size of precipitates, and their distribution in the sample. Microstructural parameters obtained from the SAXS analysis were used to explain the local hardness change in the interface area. Within the single interdiffusion layer of AlZnMg alloy, both of the Orowan and cutthrough mechanisms were observed. TEM imaging was used with the same projection of SAXS to analyze the various shapes of the precipitates to explain the anisotropy in the 2-dimensional scattered intensity measured via SAXS. The present results revealed the spatial distribution of nanostructures with averaged parameters and explained the local mechanical properties within the interface region of the multilayer composite sheets.

Effect of Al/Mg Ratio on the Microstructure and Phase Distribution of Zn-Al-Mg Coatings

“…However, partial studies show that due to the relatively poor stress-strain behavior of MgZn 2 , it is easy to produce cracks during deformation processing, which leads to a decrease in the material performance. Therefore, controlling the MgZn 2 phase in the coating is a key factor for the coating properties [16,17].…”

Small-angle scattering tomography of precipitation-hardened multilayer Al/Al-Zn/Al model alloys

“…For example, Sato et al 14) examined Al-Mg/ Al-Zn 5 alternative multilayer sheets by scanning SAXS. Such one-dimensional scanning measurements can be useful to understand spatially modulated nanostructures, [14][15][16][17][18] if the multilayer sheets are homogeneous along the beam, and changes only in the direction normal to the layer interface in the edge-view configurations. In some cases, the distribution is heterogeneous in-plane, sometimes due to undulation or local damage during rolling or additional processes such as machining, jointing, or welding.…”