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Aluminum–Magnesium (Al–Mg) alloys undergo sensitization, i.e., the precipitations of β-phase (Al2Mg3) at the grain boundaries, when exposed to elevated temperature. This microstructural change increases the susceptibility of Al–Mg alloys to intergranular corrosion, exfoliation, and stress corrosion cracking. This study introduces a time-frequency analysis (TFA) technique to determine the frequency-dependent ultrasonic attenuation parameter and correlate the frequency-attenuation slope to the Degree of Sensitization (DoS) developed in heat-treated Al–Mg alloy samples. Broadband pitch-catch signal was generated using a laser ultrasonic testing (LUT) system, from which the narrowband pitch-catch signal at different frequencies can be digitally generated. The attenuation parameters of sensitized Al–Mg samples were determined from these narrowband pitch-catch signals using the primary pulse-first echo (PP-FE) method. By identifying the frequency range within which the attenuation parameter is linearly proportional to the frequency, the slopes of the frequency-attenuation relationship were determined and correlated with the DoS values of the sample plates. The experimental results validate that the frequency-attenuation slope has a higher sensitivity and lower scattering as compared to other conventional ultrasonic attenuation measurement techniques.

This paper presents the results of detonation and explosion characteristics for ammonium nitrate, aluminium, and aluminium-magnesium alloy powder mixtures. The following parameters were determined: detonation velocities, blast waves overpressure and their specific impulses. The emission of radiation was recorded, and the history of temperature of the detonation products cloud was established. It was shown that addition of aluminium-magnesium alloy powder increases blast waves’ characteristics. Moreover, it increases the time of the afterburning reaction after detonation and increases the temperature of detonation products.

In engineering applications, such as automobile, marine, aerospace, and railway, lightweight alloys of aluminum (Al) and magnesium (Mg) ensure design fitness for fuel economy, better efficiency, and overall cost reduction. Friction stir welding (FSW) for joining dissimilar materials has been considered better than the conventional fusion welding process because of metallurgical concerns. In this study, dissimilar joints were made between the AA6061 (A), AZ31B (B), and AZ91D (C) combinations based on the varying advancing side (AS) and retreating side (RS). The dissimilar joints prepared by the FSW process were further characterized by tensile testing, impact testing, corrosion testing, fracture, and statistical and cost analysis. The results revealed a maximum tensile strength of 192.39 MPa in AZ91 and AZ31B, maximum yield strength of 134.38 MPa in a combination of AA6061 and AZ91, maximum hardness of 114 Hv in AA6061 and AZ31B, and lowest corrosion rate of 7.03 mV/A in AA6061 and AZ31B. The results of the properties were supported by photomicrographic fracture analysis by scanning electron microscopy (SEM) observations. Further, the performance of dissimilar joints was statistically analyzed and prioritized for preference by similarity to the ideal solution (TOPSIS) method.

An industrial technology for semi-continuous casting of large-sized ingots from wrought aluminum alloy 1580 has been developed through the use of complex modeling, including computer modeling and physical modeling. The ProCAST and ANSYS software packages equipped with the FLUENT module were used for computer modeling. The physical modeling was carried out on a laboratory semi-continuous casting unit (SCCU), which represents a tenfold reduced physical model of an industrial casting unit for the vertical semi-continuous casting of ingots from aluminum alloys. An aluminum-magnesium alloy with the addition of 0.05% (wt.) of scandium was used as the object of modeling. The results of computer modeling were tested at the SCCU, and then computer modeling was carried out for casting a large ingot. According to the modes obtained in the simulation, an ingot with a section of 1310 × 560 mm was cast under industrial conditions, which had a good surface quality with the absence of casting defects. In the microstructure of an industrial ingot and an ingot cast on the SCCU, there were no primary intermetallic compounds Al 3 (Sc, Zr), which makes it possible to strengthen the alloy upon annealing. To check the manufacturability during rolling, billets with a size of 40 × 120 × 170 mm were cut from these ingots, which were hot-rolled to a thickness of 5 mm, and then cold rolled to a thickness of 1 mm. The rolling results revealed good workability of the alloy, which was reflected in the high quality of the surface and the absence of cracks at the edges of the rolled stock. The mechanical properties of sheets obtained from both ingots were at the same level, which proves the reliability of casting modes for ingots obtained by complex modeling and the validity of their use for industrial conditions of the semi-continuous casting of large ingots from aluminum alloys.

Welding of dissimilar magnesium alloys and aluminum alloys is challenging due to the formation of interlayers composed of brittle intermetallic compounds (IMCs) at the bonding interface, which reduces the bonding strength. In our studies, we applied explosive welding to facilitate dissimilar welding of magnesium alloys and aluminum alloys. This method utilized a high-speed impact from an explosive to bond magnesium alloys and aluminum alloys in a short time, effectively suppressing the formation of the interlayer. Our research confirmed the presence of a thin interlayer of the γ-Mg17Al12 phase at the interface of the cladding plates. The alloy compositions of both magnesium alloys and aluminum alloys influenced the thickness of this interlayer. Furthermore, annealing of the cladding plates increased the thickness of the interlayer, resulting in the formation of the aluminum-rich β-Al3Mg2 phase on the aluminum alloy side after annealing at 473 K. The formation of the brittle β-Al3Mg2 phase led to crack initiation, which reduced the shear strength. In terms of corrosion resistance, the corrosion weight loss of the explosively welded cladding plates was slightly less than that of mechanically fastened samples. Therefore, it can be concluded that explosive welding is highly effective for bonding magnesium alloys to aluminum alloys.

The article examines plasma sprayed 95Ni-5Al coatings on alu-minum-magnesium (Mg ≈ 2,6‒3,6 %) alloy substrate. Alumi-num-magnesium samples prior spraying were prepared with mechanical treatment (blasting with Al2O3). 95Ni-5Al coatings on aluminum-magnesium alloys were sprayed with different parameters of process and coating‘s thickness, porosity, micro-hardness and microstructure were evaluated. Also numerical simulations in electric and magnetic phenomena of plasma spray-ing were carried out. Straipsnyje nagrinėjamos plazminiu būdu užpurkštos 95Ni-5Al dangos ant aliuminio-magnio (Mg ≈ 2,6–3,6 %) lydinio substrato. Aliuminio-magnio substratų paviršiai prieš purškimą buvo apdorojami mechaniniu apdorojimo būdu (srautinimas Al2O3 dalelėmis). Naudojant skirtingus plazminio purškimo proceso parametrus, buvo užpurkštos nikelio-aliuminio dangos ant aliuminio-magnio lydinių. Nustatytas užpurkštų dangų storis, akytumas ir mikrokietis. Buvo atlikta užpurkštos 95Ni-5Al dangos mikrostruktūros analizė. Darbe taip pat atliktas plazminio purškimo elektrinių ir magnetinių reiškinių skaitinis modeliavimas.

To our knowledge, no magnetic B2 phase in the Al–Mn system of near-equiatomic compositions has been reported so far. Here, we investigate the structural and magnetic characteristics of Al[sub.45] Mn[sub.41.8] X[sub.13.2] (X = Fe, Co or Ni) alloys. We demonstrate that adding 13.2 atomic percent magnetic 3d metal to AlMn stabilizes a ferromagnetic B2 structure, where Al and X occupy different sublattices. We employ density functional theory calculations and experimental characterizations to underscore the role of the late 3d metals for the phase stability of the quasi-ordered ternary systems. We show that these alloys possess large local magnetic moments primarily due to Mn atoms partitioned to the Al-free sublattice. The revealed magneto-chemical effect opens alternative routes for tailoring the magnetic properties of B2 intermetallic compounds for various magnetic applications.

Using Al–Mg alloy instead of pure aluminum can improve the agglomeration and combustion characteristics of composite propellants. In this experiment, the effects of oxygen concentration and pressure on the ignition and combustion performance of Al–Mg binary alloy (with a magnesium mass content of 20%) and Al–Mg alloy mixed with ammonium perchlorate (AP) were investigated using a laser ignition test bench. The thermogravimetric results showed that the melting of aluminum, magnesium and intermetallic phases in the alloy powder occurred under argon, producing four heat absorption peaks. Magnesium evaporates at about 580 °C. In air, only one endothermic peak was observed, with oxidation occurring at approximately 510 °C. During the oxidation process, the intermetallic phase decomposes. Laser ignition tests showed that the alloy mainly undergoes gas-phase combustion, exhibiting phenomena such as gas emission, particle fragmentation, and micro-explosions. The introduction of AP promotes ignition and combustion of the alloy, resulting in more intense gas-phase reactions. Both increased pressure and oxygen concentration will promote alloy combustion. There are two reaction zones in the particles during combustion. Filamentary solids were observed in the combustion products of the AP-AM samples, which were primarily the products of the reaction of magnesium with O and Cl.

In this study, the effects of Cu addition on artificial age hardening behavior and mechanical properties of Al-1.2Mg-1.2Si-(xCu) alloy was investigated quantitatively and qualitatively by Vickers hardness, tensile test, and transmission electron microscope. The results indicated that Cu addition enhanced the aging response of the alloy at 175 °C. With the increase in Cu content, the time for the alloys to reach peak aging decreased from 12 h to 10 h and 8 h. The tensile strength of the alloy was obviously improved with Cu added in which was 421 MPa of 0Cu alloy, 448 MPa of 0.18Cu alloy, and 459 MPa of 0.37Cu alloy. The results of TEM observation revealed that the addition of 0.37Cu changed the aging precipitation sequence of the alloy, in which the precipitation sequence of 0Cu and 0.18Cu alloy was SSSS→GP zones/pre-β″→β″→β″ + β′, 0.37Cu alloy was SSSS→GP zones/pre-β″→β″ + L→β″ + L + Q′. Moreover, with the addition of Cu, the number density and volume fraction of precipitates of the Al-1.2Mg-1.2Si-(xCu) alloy was evidently increased. The number density was increased from 0.23 × 1023/m3 to 0.73 × 1023/m3 in the initial aging stage and from 1.9 × 1023/m3 to 5.5 × 1023/m3 in the peak aging stage. The volume fraction was increased from 0.27% to 0.59% in the early aging stage and from 4.05% to 5.36% in the peak aging stage. It indicated that Cu addition promoted the precipitation of strengthening precipitates and boosted the mechanical properties of the alloy accordingly.

Wire arc additive manufacturing (WAAM) of aluminum-magnesium (Al–Mg) ER5356 alloy deposits is accomplished by cold metal transfer (CMT). During the process, the temperature change of the alloy deposits has a great influence on molding quality, and the microstructure and properties of alloy deposits are also affected by the complex thermal history of the additive manufacturing process. Here, we used an inter-layer cooling process and controlled the heat input process to attempt to reduce the influence of thermal history on alloy deposits during the additive process. The results showed that inter-layer cooling can optimize the molding quality of alloy deposits, but with the disadvantages of a long test time and slow deposition rate. A simple and uniform reduction of heat input makes the molding quality worse, but controlling the heat input by regions can optimize the molding quality of the alloy deposits. The thermophysical properties of Al-Mg alloy deposits were measured, and we found that the specific heat capacity and thermal diffusivity of alloy deposits were not obviously affected by the temperature. The microstructure and morphology of the deposited specimens were observed and analyzed by microscope and electron back-scatter diffraction (EBSD). The process of controlled heat input results in a higher deposition rate, less side-wall roughness, minimum average grain size, and less coarse recrystallization. In addition, different thermal histories lead to different texture types in the inter-layer cooling process. Finally, a controlled heat input process yields the highest average microhardness of the deposited specimen, and the fluctuation range is small. We expect that the process of controlling heat input by model height region will be widely used in the WAAM field.