Effect of Mn‐Bearing Dispersoids on Tensile Properties and Recrystallization Resistance of Al‐3Mg‐0.8Mn Rolled Alloy

As a traditional nonage‐hardenable aluminum alloy, 5XXX aluminum alloy has a limited dispersion‐strengthening effect since it is challenging to obtain high‐density and fine‐sized dispersoids by a conventional homogenization treatment process. In this work, three different homogenization treatments, single‐stage homogenization, slope heating homogenization, and double‐stage homogenization are used in a new type Al–Mg–Mn–Er alloy to exploit the dispersion strengthening. The precipitation behavior of submicron‐sized Mn‐containing dispersoids and nanosized Al3Er precipitates is investigated. In single‐stage homogenization, the nucleation of the Mn‐containing dispersoid is completed within a span of 2 h at 460 °C, accompanied by noticeable coarsening and the Al3Er precipitate tended to nucleate at dislocation sites and form a chain‐like structure. In slope heating and double‐stage homogenization, during the initial phase of heat treatment, lower temperatures facilitate the nucleation of dispersoids. This leads to the uniform precipitation of Mn‐containing dispersoids within the grain interior and improves the chain distribution of the Al3Er precipitates. The double‐stage homogenization generates the finest dispersoids. The alloy reaches maximum strength in the double‐stage homogenization, and the yield strength is 177 MPa, representing a 22% increase compared to the single‐stage homogenization.

Effect of Homogenization on Microstructure and Mechanical Properties of Al–Mg–Mn–Er Alloy

Shen,

Yao,

Yang

et al. 2024

Surface Property Enhancement of Al–Si–Cu Alloy Coating by Fast Multiple Rotation Rolling

Bararpour,

Jamshidi Aval,

Jamaati

et al. 2024

In this study, the effect of high rotational speed fast multiple rotation rolling (FMRR) on the microstructure, mechanical properties, and wear resistance of an Al‐Si‐Cu alloy coating friction surfaced on AA1050 aluminum alloy was investigated. The FMRR process was performed at a rotational speed of 3000 rpm with traverse speeds of 50, 80, 110, and 140 mm/min. The microstructure, mechanical properties, and wear resistance were examined by optical microscope, scanning electron microscope, electron backscatter diffraction (EBSD), transmission electron microscope (TEM), nanoindentation test, microhardness test, and pin‐on‐disc wear test. The results showed that as the traverse speed increased from 50 to 140 mm/min, surface roughness decreased from 6.3±0.3 to 3.2±0.2 µm. Additionally, with the increase in traverse speed, the coating height increased from 3.8±0.3 to 4.7±0.4 mm, while the coating width decreased from 37.1±1.1 to 25.4±1.3 mm. Furthermore, as the traverse speed increased from 50 to 140 mm/min, the average hardness of the FMRR processed layer increased from 5.6±0.6 to 10.2±0.6 GPa. At a traverse speed of 140 mm/min, the wear resistance of the FMRR processed layer increased by 20% compared to the Al‐Si‐Cu alloy consumable rod.This article is protected by copyright. All rights reserved.

Microstructure, Mechanical, and Corrosion Performance of AA4343/AA3003/AA4343 Laminated Sheets Subjected to Cryorolling and Annealing

Samdane,

Guo,

Cui

et al. 2024

The effects of cryorolling (CR), hot rolling (HR), and different annealing temperatures on the microstructure, mechanical, and corrosion performance of AA4343/AA3003/AA4343 laminated sheets are studied. Compared with the HR samples, the microstructure of the CR samples presents a significant decrease in the size of elongated grains and significantly large second‐phase particles Al(Mn, Fe)Si in the AA3003 alloy. Grains in CR samples subjected annealing at 200–300 °C become finer. Increasing to 400–550 °C, the grains begin to grow, and the Si is diffused into the core layer. A comparison of HR and CR processing reveals a significant increase in the yield strength from 153 to 209 MPa and the ultimate tensile strength from 168 MPa to 217 MPa of the laminated sheet. Potentiodynamic polarization measurements and immersion tests are conducted to assess the corrosion morphology. After being immersed in a 3.5% NaCl solution for two weeks, the clad surface of the laminated sheet exhibits uniform corrosion products and pitting corrosion, which shows the pitting corrosion depth of the CR sample improved compared to the HR sample. The study suggests that both CR and annealing can be useful for enhancing the mechanical properties, and corrosion morphology of laminated sheets.