Influence of Iron Content on the Mechanical Properties of AA6016 Alloy Sheet

Abstract

The influence of the iron content from 0.1 to 1.0 mass% on the mechanical properties of AA6016-T4 sheets was investigated. The amount of the Al-Fe-Si second phase particles increased with the iron content, thus the solute silicon atoms decreased. Increasing of the Al-Fe-Si particles lowers the bendability, while decreasing of the solute silicon atoms lowers the paint bake response (PBR) and improves the bendability. The bendability of the samples then became the worst at the 0.5 mass% iron content, while it at 0.8 and 1.0 mass% became better or the same as that at 0.5 mass%. The increasing of the silicon content in the 1.0 mass% iron content alloy improved the PBR and lowered the bendability.

Influence of quench rate and microstructure on bendability of AA6016 aluminum alloys

“…A likely explanation is that the onset of cracking is due to textureinduced strain localization enhanced by the presence of large intermetallics particles. This explanation is consistent with the usual view that considers cracks to be initiated around large intermetallics particles within shear bands that form while these alloys are subjected to bending (see Introduction) [2,3,[5][6][7]19,21,23,26,36,37]. Neither grain structure nor intermetallic particles being influenced by the cooling rate, this is consistent with present data.…”

“…The formability can thus be improved by promoting the formation of a particles instead of b particles when the alloy is homogenized; this can be accomplished by increasing the temperature and/or time of homogenization [10,14,15] or by adding a-stabilizer elements such as Mn [8,[15][16][17][18]. Regardless of particle type, alloys with a high content of Fe [2,3,5,[19][20][21] or Si [20,22,23] are generally recognized to have a poorer formability due to a higher quantity of intermetallic particles; however, we note that Davidkov et al [24]considered recently that large micron-size Mg 2 Si particles formed on grain boundaries are the critical parameter promoting fracture of alloy AA6016 during bending, rather than large AlFeSi intermetallic particles [24].…”

Microstructure controlled bending response in AA6016 Al alloys

“…The Fe content in these alloys influences the volume fraction of the coarse non-deformable constituent particles which are considered as strongly involved into the fracture process during bending by their role in voids formation [24,25]. Part of the excess Si is also consumed by those particles, but however the sufficiently high excess of Si in both alloys provides the further formation of strengthening phases.…”

Three-Point Bending of Heat-Treatable Aluminum Alloys: Influence of Microstructure and Texture on Bendability and Fracture Behavior

“…Constituent particles in metals are found to be natural nucleation sites for microvoids. [6] Dao and Li [12] and Wilkinson et al, [13] however, suggest that the particles also affect the formation of shear bands during bending, which essentially leads to fracture. Shear localization plays a major role in fracture initiation.…”