The influence of dispersoids on the recrystallization of aluminium alloys

Abstract

The influence of dispersoids on the softening processes in twin-roll cast and cold-rolled Al -Fe -Mn -Si aluminium alloy was studied. Before rolling, the specimens were thermo-mechanically pre-treated in order to create a different second-phase dispersion. The influence of the initial microstructure was studied by means of electrical resistivity, light and electron microscopy. The evolution of softening was monitored by microhardness measurements. The depletion of the Al matrix from solutes connected with formation of a dense dispersion of precipitates results in the enhancement of (sub)grain-boundary mobility. As a consequence, full recrystallization occurs at lower temperatures in preannealed specimens with low solute concentrations. The presence of coarser precipitates formed during the pretreatment results in the formation of a fine-grained microstructure.

Influence of cold rolling on the precipitation in an Al–Mn–Zr alloy

“…5a). This is in agreement with observations in Al-Mn-Zr [15] and Al-Fe-MnSi alloys [16]. ii) The material deformed 87% shows similar kinetics as the one cold rolled with 39% reduction, the corresponding major peak in Fig.…”

“…7) was not successful. So the tiny particles should be of the frequently observed cubic α-Al(Mn,Fe)Si phase [4,5,8,15,16] or modified Al 3 Zr phase with crystal structure different from L1 2 . This is in agreement with our previous observations [15] and also with the results of Poková [19,20] who found heterogeneously, but densely distributed tiny Al 3 Zr particles and diffraction spots corresponding to L1 2 crystal structure after precipitation annealing only in the as cast alloy, but not when the precipitation annealing was applied to cold rolled sheets.…”

The Evolution of Microstructure and Mechanical Properties of Al-Mn-Fe-Si Alloys During Isothermal Annealing

“…Linear relation between the logarithm of time necessary to 50% recrystallization tRX to the reciprocal of the annealing temperature T , used for the calculation of activation energy QRX . hance recrystallization resistance [5,22]. This is the case of the non-annealed material, where new α-Al(Mn,Fe)Si particles form during annealing and enhance the recrystallization resistance in the same extent as Al 3 Zr precipitates in the pre-annealed alloy.…”

Resveratrol prevents global cerebral ischemia-induced decrease in lipid content

“…Next to the primary particles, which appeared during the casting process, new dispersoids precipitate during annealing at elevated temperatures [1]. In AW3003 alloys, the temperature of main precipitation has been observed between 300 and 500 • C [26].…”