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The corrosion fatigue cracks propagation behavior of A7N01P-T4 and A7N01S-T5 aluminum alloys in 3.5 wt.% NaCl solution and air were studied by single side notch corrosion fatigue tests (SNET). The crack growth rate (da/dN) was measured and the crack propagation mechanism was analyzed by scanning electron microscopic analysis. The results showed that the corrosion fatigue cracks growth rate of A7N01S-T5 alloy in air and 3.5 wt.% NaCl solution is faster than that of A7N01P-T4 alloy. The crack propagation follows a mixed intergranular and transgranular mode. The anodic dissolution and hydrogen embrittlement accelerate the propagation of corrosion fatigue crack of 7-series Al alloy in 3.5 wt.% NaCl solution. The corrosion resistance and fatigue crack propagation are related to the strength of the alloys and the density of grain boundaries.

In this paper, squeezing transport of radiative water conveying aluminum alloys (i.e., AA7072 and AA7075) mobilized by entropy generation and dissipative energy is analyzed. Problem is formulated in a rotating frame with the consideration of magnetohydrodynamics and Joule heating aspects. Maxwell model for nanofluid has been used to incorporate the thermophysical properties of nanoelements. Formulated governing expressions have been transformed into system of ODEs by introducing similarity variables. The transformed system of ODEs is then numerically solved by Runge–Kutta–Fehlberg (RKF) method based on shooting background. The physical quantities (i.e., skin-friction coefficient, Nusselt and Bejan numbers) of scientific interest are formulated and illustrated via various plots. Graphical representations of squeezing function, temperature profile and velocity profile have been made to examine the effects of involved parameters. Streamlines and isotherms patterns have been formed and discussed. To authenticate the validity of model, skin-friction values have been compared with published literature for limited version of the model. Entropy and temperature of the system are improved with the involvement of aluminum alloys in water. Symmetrical behavior of streamlines is observed for positive approach of squeezing parameter.

The mechanical and thermodynamic behaviors of intermetallics in Al–Zn–Mg–Cu alloys are studied by first-principles calculations. All studied second phases have negative values of formation enthalpy and cohesive energy indicating their excellent thermodynamic stability. Al₃Er_D0${}_{22}$ has the most significant metallic nature, while Mg₂Si shows the least metallicity. TiAl₃ shows the highest bulk, shear, and Young’s moduli. All Al₃M polymorphs, Mg₂Si and TiAl₃ phases show covalent/metallic hybrid bonding. The mechanical anisotropic behaviors obey the trend of: MgZn${}_2>{\mathrm{\text{Al}}}_3$Er_D0${}_{22}>{\mathrm{\text{Al}}}_3$Sc_D0${}_{22}>{\mathrm{\text{TiAl}}}_3>{\mathrm{\text{Al}}}_3$Sc_D0${}_{23}>{\mathrm{\text{Al}}}_3$Er_D0${}_{23}>{\mathrm{\text{Al}}}_3$Er_L1${}_2>{\mathrm{\text{Al}}}_3$Sc_L1${}_2>{\mathrm{\text{Mg}}}_2$Si, where MgZn₂ is the most mechanically anisotropic phase. The calculated room-temperature linear thermal expansion coefficient values for the studied phases are from $10.2\times 10^{-6}$ K${}^{-1}$ to $21.2\times 10^{-6}$ K${}^{-1}$; where Al₃Er_L1₂ has the highest value ($17.3\times 10^{-6}$ K${}^{-1})$, followed by Al₃Sc_L1₂ ($15.5\times 10^{-6}$ K${}^{-1})$; both of which are close to that of the Al matrix, thus making the relatively lower thermal misfit.

A kind of environment-friendly anodic oxidation technology was used to oxidize 2024 aluminum alloys from mixed acid solutions to effectively improve the anticorrosion and mechanical performances. The influences of anode oxidation method on surface morphology, microstructure, composition, electrochemistry parameter, anticorrosion property were studied. Aluminum alloy oxidation is actually a dynamic equilibrium process of the formation and dissolution of oxide film which is composed of porous and non-porous layer. With the treatment of anodic oxidation, $\alpha$-Al₂O₃ and $\gamma$-Al₂O₃ structures were obtained on the surface of aluminum alloys, which contributed directly to the increase of anticorrosion performance. The potassium dichromate solution was used to seal the surface of oxide films to further improve the anticorrosion property. The oxide films sealed with potassium dichromate were covered with leaf-like structures resulting in larger corrosion resistance that attributed directly to the decrease of corrosion current.

Aluminum (Al) and its alloys are attractive for a variety of applications due to its advantages like light weight, ease of processing, and high thermal/electrical conductivities. However, it suffers short comings in terms of strength, wear resistance, and corrosion resistance. Thermal spray processes are widely used techniques for the surface property improvement like thermal, wear, and corrosion resistances of aluminum and other light metals. This paper summarizes the recent developments in thermal spraying and related technologies. Plasma spraying, flame spraying, and arc spraying are the chief thermal spraying techniques, whereas the HVOF and D-gun processes are the derivatives of flame spraying process. The cold spraying technique is an emerging coating technique where the particles are heated to a temperature lower than their melting point travel at high velocity and coat on impact with the target material by plastic deformation. Different parameters like heat source characteristics, coating material properties, substrate properties, and spray torch operating circumstances affect the coating microstructure and properties.

The main objective of this study was to assemble by friction stir welding two dissimilar sheets made with AA5754 Al-Mg alloy and AA 1050 aluminum, which are intensely used in the automotive industry. The applied welding speed was 75mm/min with different tool rotational speeds (780, 1330 and 2440rpm). The mechanical properties and the microstructure of the welded joint were investigated by the tensile test, the three-point bending test, the microhardness measurements, the optical microscopy, scanning electron microscopy and energy dispersion spectrometry (EDS). The main zones were observed in the welded joint. Optimum mixing was achieved during the assembly process with a welding tool rotation speed of 2440rpm. It was determined that the microstructures formed had a significant effect on the hardness and tensile strength of welded dissimilar materials such as the precipitated phases in the nugget zone. The best result in terms of tensile strength was obtained at 780rpm with 80% performance.

Friction stir welding (FSW) is a process that can join many materials by causing minimal internal stress without the need for a direct electric current, contrary to traditional welding methods. The effects of SiC and Al₂O₃ reinforcing powders on the joining of AA6061-T6 and AA7075-T6 plates, which are difficult to join with conventional welding methods by FSW, are investigated in this study. The metallurgical properties of the combined samples are examined in terms of strength characteristics to investigate the effects of the reinforcement powder. In addition, elemental analysis is carried out for the mixing behavior of the powders. Finally, we used the TOPSIS method to select the most appropriate powder types to improve welding quality. Furthermore, a game theory application is presented to determine which powder type is suitable considering the joined aluminum plate’s strength expectations.

The problem of scattering of electromagnetic waves is one of the most essential problems of electromagnetic theory and presents a significant interest in both theoretical and practical applications (e.g. telecommunications, electromagnetic interaction, biomedicine, remote sensing, etc.) The solution to such a problem involves the computation of surface or spatial current density on scatterers followed by the computation of scattering field (near or far) as well as various other parameters (i.e. scattering cross section). For real scatterers the scattered field is also a function of their electrical characteristics beyond all other parameters that are involved in such problems. This paper investigates the impact of the electrical characteristics of several materials to the scattered electromagnetic field.

Hot stamping of Aluminum alloys is a process receiving increased interest from the automotive industry. However, during this process, galling, which has been recognized as one of the major drawbacks, limits the tool life and restricts the complexity and quality of the product. In order to improve the feasibility of this forming technology, an understanding of the mechanism of galling is necessary. The aim of the present study is to investigate the galling behaviours between AA6082 and two advanced anti-wear coatings, CrN and AlCrN. The study was conducted with pin-on-disc experiments at an elevated temperature. The main focus of the study is on the quantitative measurement of galling and identifying the material transfer mechanisms between Aluminum and tool surface.

To improve the formability and productivity in cold stamping of aluminum alloys, warm forming and hot forming processes were developed, in which heating process plays an important part. This paper presents investigations on direct contact heating of aluminum sheets by the approach of modeling. The influence factors of working face temperature uniformity of the direct contact heating device were studied, as well as the continuous heating of aluminum sheets by direct contact heating process. Simulation results indicate that direct contact heating process can realize continuous quick heating of aluminum sheet, and the solution heat treatment of aluminum alloys can also be achieved. In the process of direct contact heating, the heating time is short, the temperature of the heated sheets is relatively uniform, and there is little difference of temperature distribution between different sheets in same heating condition. The direct contact heating process represents a feasible as well as time-saving alternative for the heating of aluminum alloys.