Effect of Geometrical Parameters of Microscale Particles on Particle-Stimulated Nucleation and Recrystallization Texture of Al-Si-Mg-Cu-Based Alloy Sheets

Abstract

The effects of the shapes (needle and round) and volume fractions (low and high) of microscale particles in Al-Si-Mg-Cu-based alloys on recrystallization behavior, texture evolution, mechanical properties, and formability are investigated. The recrystallized grain size decreases as the size and volume fraction of the particles decrease and increase, respectively, regardless of the particle shape. The investigated alloys with a relatively low volume fraction of 0.7 to 2.4 vol.% exhibit higher efficiency particle-stimulated nucleation (PSN) than alloys with a high volume fraction of 6.0 to 21.0 vol.%. This is because the interaction between the particles and dislocations cannot be greatly promoted when the volume fraction of the particles is large enough to form agglomerates. The sheets with round-shaped particles exhibit higher yield strength (YS) and elongation (EL) than sheets with needle-shaped particles. The improvement in YS is due to the combined effects of grain refinement and particle strengthening, and the EL is improved by reducing the probability of cracking at the tips of round-shaped particles. The sheets with round-shaped particles exhibit relatively higher average plastic strain ratio (r¯) and planar anisotropy (∆r) than the sheets with needle-shaped particles, owing to the development of Goss {110}<001> or rotated-Goss {110}<110> orientations.

Particle Stimulated Nucleation Effect for Al-Mg-Zr-Sc Alloys with Ni Addition during Multidirectional Forging

“…The particle stimulated nucleation effect is deeply studied [40][41][42][43][44]. The PSN is observed in heterogeneous alloys containing coarse undeformed particles of the secondary phases [45][46][47][48]. During the plastic deformation processes the areas around the particles accumulate lattice misorientations.…”

A Short Review on Superplasticity of Aluminum Alloys

“…Metallic alloys that exhibit superplastic behavior include: titanium, magnesium, duplex stainless steels and aluminum alloys [4]. Among them, Al alloys have found extensive SPF application in the automobile sector due to the need to reduce the weight and minimize fuel consumption and hence greenhouse effect [11]. Superplastic Al alloys are usually employed for fabricating automobile body panels.…”