The Effect of Extrusion and Heat Treatment on the Microstructure and Tensile Properties of 2024 Aluminum Alloy

Abstract

Hot extrusion forming is one of the best cost-effective processing methods to obtain high-strength aluminum alloys. In order to obtain high performance 2024 aluminum alloy for the aero and automobile industries, this research comprehensively uses heat treatment and reverse isothermal extrusion technology to prepare 2024 alloy. The effects of homogenization, extrusion and post-extrusion annealing treatment on the microstructure and mechanical properties of 2024 aluminum alloy were discussed in detail. The results indicate that the grain refinement of the extruded alloy material is significant. The coarse eutectic microstructure at the grain boundaries was refined, and these grains tended to be uniformly distributed after the annealing treatment. Extruded 2024 aluminum alloy material mainly has S (Al2CuMg) and Al7Cu2Fe second phases. The appearance of a large number of S phases led to a significant improvement in the properties of the alloy with an increase in tensile strength and elongation of 176% and 547%, respectively. In addition, EBSD analysis showed a significant meritocratic growth in the extrusion direction with the appearance of Copper {112} <111> rolling weaving, which led to process hardening and the strength improvement of the alloy.

Effect of Lattice Constants and Precipitates on the Dimensional Stability of Rolled 2024Al during Isothermal Aging

“…It can be seen that only the aluminum peaks can be observed in the sample at this time. In Figure 6 b, it can be seen that not only the aluminum peak but also the Al 2 CuMg (S phase) peak exist in the rolled plate after aging for 72 h, which is consistent with the observation in the literature [ 35 ], indicating that Al 2 CuMg phase precipitates from the rolled plate after aging for 72 h.…”

The Effects of Titanium Dioxide (TiO2) Content on the Dry Sliding Behaviour of AA2024 Aluminium Composite

“…Second, the sample was placed in an electric furnace (Gallen Hamp hot stop BR-17M / XD-17M) for 3 hours to achieve the aging (precipitation heat treatment) stage between 180 ºC to 190 ºC, followed by cooling in air. Figure 3 demonstrates a schematic diagram of the sequenced heat treatment processes [25]. The digital Vickers hardness analyser category Laryea (HBRVS-18705) was also used to determine the sample's hardness.…”

Microstructure and mechanical properties of extruded TiB2/2024 aluminum matrix composites

“…There are two main reasons for the substantial improvement in the properties of the extruded alloy: on the one hand, hot extrusion eliminates internal casting defects in the material; on the other hand, during the extrusion process, the grains and agglomerated TiB 2 particles break under the action of three-way compressive stress, which further promotes grain refinement and facilitates the uniform distribution of the reinforcing phase particles, the presence of some high-angle grain boundaries endows the alloy with a greater capacity to regulate the plastic deformation of grain boundaries, thereby augmenting its plasticity by virtue of its capacity to absorb more energy during the fracture process; on a macroscopic scale, this leads to a substantial improvement in the mechanical properties [25]. However there are some reasons that can reduce the performance of the composite, such as the salt film coating the generated TiB 2 particles reduces the strengthening impact of TiB 2 and processing casting defects are diverse and can range from porosity, segregation, hot tears, and the generation of hydrides and oxides [26,27].…”