The Effect of Particles on Recrystallisation Textures and Microstructures

Abstract

The way in which large and small particles influence on recrystallised grain size and texture is considered with special emphasis on the processing of aluminium. It is well known that large particles might induce nucleation of recrystallised grains, while finely dispersed small particles will exert a pinning force on boundary movement. It the present paper, these two effects of particles will be discussed in detail. The discussion will to some extent be in an overview form, but also new ideas and recent experimental results will be presented. These include cases where strong effects are caused by small precipitated particles.KEY WORDS: Aluminium, recrystallisation, particle stimulated nucleation, particle pinning obtain a size 3rl, where rl is the particle size. Based on this, the growth criterion of Eq. (1) can be reformulated as follows:

Evolution of microstructure and mechanical properties during annealing of cold-rolled AA8011 alloy

“…Generally Si and Al 3 Fe particles precipitate during annealing of the cold-rolled alloy AA8011 [7]. Precipitation of particles at grain boundary affects the migration as well as shape of the boundary [25]. Vatne et al [25] have reported several characteristics of recrystallized grains like elongated, island and ragged shape grains owing to the effect of precipitates.…”

Recrystallization Behavior of Commercial Purity Aluminium Alloys

“…Table 1. Major components of the recrystallization texture for some particle containing alloys [58] The effect of PSN on recrystallization texture is as follows [59]:…”

“…It is already discussed in §4.8.2 that Al 3 Fe particles suppress the cube texture formation. Cube grain growth is also inhibited by "orientation pinning" [59].…”

“…From Table 2.2 it is observed that for the alloys (e.g., Al-FeSi or Al-Si) containing low volume fraction of particles, cube and rolling components are developed, whereas rolling and random components develop for high volume fraction of particles containing alloys (e.g., Al-Ni). The cube grains are larger than randomly oriented grains owing to the faster growth rate of former [59]. It results in formation of small island grains inside the large cube grains.…”

A mean field model of dynamic and post-dynamic recrystallization predicting kinetics, grain size and flow stress

“…Numerical models [29][30][31] accounting for recrystallization during and after hot deformation for aluminum alloys were developed, such as the ''Through Process Model'' for the production processes of aluminum [32]. It should be noted that, different from austenitic stainless steels, aluminum alloys are of high stacking fault energy and recrystallization is characterized by the gradual formation and appearance of a new structure with no identifiable nucleation and growth stages.…”