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Dynamic softening behavior of Al−18Si alloy produced by spray forming

“…The occurrence of DRX mainly depends on the chemical composition of the material and deformation variables, such as strain, strain rate, and temperature. In particular, the occurrence of DRX brings about grain refinement and reduction of deformation resistance in practical forming processes [2,[4][5][6]. Thus, the flow stress curve can be classified as two different types and its schematic diagram is shown in Fig.…”

“…Usually, Al and Al-based alloys of high stacking fault energy show either DRX or DRV flow curves during high temperature deformation. Alloying elements and particles induce DRX either by diminishing the stacking fault energy or by pinning dislocations in the walls; these pinned dislocations are defined as polygonized subgrains [2,[4][5][6][7][10][11][12]. Fig.…”

“…It is necessary to properly express the dependence of flow stress on deformation variables such as temperature and strain rate. The relationship among strain rate, temperature, and flow stress can be expressed by a power function combined with the Arrhenius-type temperature sensitivity term [2,[4][5][6][10][11][12]. As a result, the effects of strain rate ( ) and temperature (T) on peak stress (σ p ) can be obtained as follows:…”

“…In the last few years, there has been extensive research on the dynamic softening mechanism for Al alloys including Al matrix composites at high temperatures [4][5][6]. For example, it has been reported that Al 2024 composite reinforced with SiCp produced by powder metallurgy was softened by both dynamic recovery (DRV) and dynamic recrystallization (DRX) during hot deformation [5,6].…”

“…For example, it has been reported that Al 2024 composite reinforced with SiCp produced by powder metallurgy was softened by both dynamic recovery (DRV) and dynamic recrystallization (DRX) during hot deformation [5,6]. The dynamic softening behavior, DRV or DRX, is found to depend on strain rate and deformation temperature.…”