Hot deformation behaviour of Thixocast A356 aluminum alloy during compression at elevated temperature

Abstract

In present study, the flow behaviour and constitutive equation of Thixocast A356 Al alloy has been studied using hot compression test at 450°C, 500°C, 540°C under the strain rates of 0.0001 sec -1 , 0.0005 sec -1 , 0.001 sec -1 , 0.01 sec -1 . The compression flow curves exhibited an initial sharp increase with strain followed by a moderate work-hardening behaviour. The maximum stress was decreased as the strain rate reduced and the temperature increased. At the lowest examined temperature (450°C) and the highest applied strain rate (0.01 sec -1 ), a flow softening behaviour was observed. This was attributed to the morphological changes of the present precipitates.

Effect of Zr, V and Ti on hot compression behavior of the Al–Si cast alloy for powertrain applications

“…The related parameters, such as peak stress, temperature, and strain rate, can be expressed using the following equations [10,11], …”

“…Due to the presence of non-deformable and brittle eutectics or primary silicon phase, the hot workability of the AlSi alloys is rather limited [8]. There have been studies [9][10][11] that focused on hot deformation of Al-Si alloys with near-eutectic or hypereutectic compositions. Ding et al [9] reported a good combination of tensile strength and elongation for hot extrusion of the Al-12Si-0.2Mg (wt.%) alloy.…”

“…Ding et al [9] reported a good combination of tensile strength and elongation for hot extrusion of the Al-12Si-0.2Mg (wt.%) alloy. Other studies [10,11] reported the hot deformability of hypereutectic Al-Si alloys at different strain rates and temperatures with a conclusion that to prevent coarsening of the eutectic silicon, the spray-formed hypereutectic Al-Si alloy should be hot extruded below 500°C.…”

“…They also reported that the combinations exceeding 0.2%Zr and 0.2%Ni in the Al-Si-Cu-Mg base decreased the alloy performance. The previous studies have been focused mainly on determining various material constants in the constitutive equations describing the hot deformation behavior [10,11,[23][24][25][26][27][28][29]. However, according to the authors' knowledge, there is no study on the impact of addition of transition metals, especially Ti, V and Zr in Al-Si-Cu-Mg alloys on the hot deformation behavior.…”

Finite Element Analysis and Experimental Study on the Effect of Extrusion Ratio during Hot Extrusion Process of Aluminium Matrix Composites

“…The sudden decrease in the strain at the temperature of 450 °C was due to the work softening/dynamic recovery of aluminium alloy due to plastic deformation process. At this temperature, the rate of work hardening is offsetting due to the work softening effects of dynamic recovery 17 . During the hot extrusion process, initial work hardening followed by dynamic recovery or softening happens.…”