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The friction spot welding process is used to join the hybrid joint of aluminium to polymer. AA 1050 Aluminum alloy and polyethylene polymer (type of plastic) were used for joining. Aluminium surface treatment was done to increase the wettability of it. The surface treatment was done by electrochemical treatment. Two parameters of the joining process were used: (1, 1.5 and 2) min. (920, 1340 and 1500) rpm for time and rotational speed, respectively. Many tests for the joint are done: shear test and Scanning electron microscopy (SEM). Using the Minitab program, the effect of the parameters on the joint was analysed. The maximum value of the shear force was (1587 N) at 1.5 min. time and 1340 rpm rotational speed. The minimum shear force was (589 N) at 1 min. time and 920 rpm rotational speed. The joints which were tested failed by an interfacial shear with a ductile fracture of the polymer side. The process of joining mechanism occurred through a mechanical interlocking between the molten polymer and the surface of the AA 1050 aluminium specimen, cohesive and adhesive. The average thickness for the joint of the tested specimens was 4μm. [ABSTRACT FROM AUTHOR]

In this study, hybrid AA1050/Al2O3/TiO2 composites have been produced via combined liquid casting and powder metallurgy techniques. Degassing was utilized to improve the wettability of molten aluminum alloys, and then successful bonding was generated between aluminum matrix and reinforcement particles during the powder metallurgy technique. As the base matrix and reinforcements, AA1050 alloy, Al2O3 and TiO2 particles were taken, respectively. Then, content values of 5Wt.% of Al2O3 in the mesh size of 20 μm and 2.5 and 5 wt. % of TiO2 particles with mesh size of 5μm were added to the AA1050 matrix. For each composite sample, ceramic particles were warmed to 600°C in order to improve wettability and distribution. An identical scattering of subdivisions was observed through aluminum (as matrix) in the microstructural study. To measure the wear resistance, the mechanism of rotary wear test was used. The achieved results illustrated that the fabrication of hybrid composites is an ideal approach to improve the wear resistance of Al-based composites. By increasing of TiO2 Wt.% up to 5% for all composite samples, the wear rate improved to less than half of the monolithic Al alloy value for each composite sample. [ABSTRACT FROM AUTHOR]

In this study, the formation of porous Al2O3 on commercial 1050 aluminium alloy (AA1050) in 2 M sulfuric acid (H2SO4) electrolyte was investigated. Anodization was performed at 12 V and 15 V specimens for a charge density of 757 mC/cm2 and 3231 mC/cm2. The resulting oxides were analyzed using scanning electron microscopy (SEM). According to analysis, a hexagonal oxide formation containing more than one nano pore was observed on the surface of the specimen. The structural properties of the porous oxide film were analyzed with electrochemical impedance spectroscopy (EIS) analysis and film-related features such as thickness of the porous and the barrier layer were obtained. [ABSTRACT FROM AUTHOR]

Polyorganosilazane (PSZ) has been used for many years as a ceramic precursor for the preparation of silicon carbonitrides. Recently, polymethyl (hydro)/polydimethylsilazane-derived coatings that can be cured with atmospheric moisture at low temperatures have attracted interest due to their hydrophobic nature and electrochemical properties. In this work, polymethyl (hydro)/polydimethylsilazane-derived coatings have been deposited on aluminum alloy AA1050. The effect of the PSZ precursor concentration (5–40 v/v%) on the final properties of the coatings has been investigated. Butyl acetate has been employed as solvent. The layers were applied on the substrate by dipping. The experimental results showed that the concentration of the PSZ in the solvent strongly affects the dry thickness of the hybrid layer. The electrochemical impedance spectroscopy measurements revealed that the coatings derived from PSZ precursor concentration higher than 20 v/v% are protective and homogenous. Contact angle measurements evidenced that the presence of the coatings increased the hydrophobicity of the substrate as well as the oleophobicity regardless of the dilution in the organic solvent. The graffiti resistance of the coatings has been demonstrated to be acceptable regardless of the dilution of the PSZ precursor, in the investigated range. [ABSTRACT FROM AUTHOR]

High-cycle fatigue (HCF) and low-cycle fatigue (LCF) fatigue lives of rolled AA1100 and AA1050 aluminum sheets along different directions were evaluated at room temperature. Four types of samples denoted as longitudinal (L) and transverse (T) to the rolling direction were compared because the samples along the two typical directions show an obvious anisotropy. A cantilever plane-bending and multi-type fatigue testing machine was specially designed for this purpose. Deflection-controlled fatigue tests were conducted under fully reversed loading. The longest fatigue lives in the LCF region were obtained for AA1050 (L) while AA1100 (L) samples had the longest fatigue lives in the HCF region. [ABSTRACT FROM AUTHOR]

Silane sol-gel coatings have been widely studied as a potential strategy to protect aluminium and aluminium alloys components and were proved to be suitable both as a chemical conversion treatment alone and as a coupling agent between the underling substrate and an organic coating. Compared with many aluminium alloys, only little investigation was carried out on the application of sol-gel coatings on AA1XXX. Despite pure aluminiumshows lower mechanical resistance with respect to aluminiumalloys, however, the high thermal conductivity makes it suitable in a huge variety of applications, such as heat exchanger constructions as well as cooling systems. The present work is devoted to the study of the effect of the surface chemical pretreatment on the structural and corrosion protection properties of a hybrid sol-gel film. Different surface chemical treatments of the 1050 aluminium alloy prior sol-gel deposition were tested: alkaline etch, acidic passivation and boiling water immersion (to promote the formation of pseudo-boehmite). Films of 1 :1 molar ratio of GLYMO:MTES were obtained on AA1050 from a 5wt% solution in acidified water. The effect of the chemical surface treatment on the AA1050 substratewas investigated both in terms ofmorphology bymeans of scanning electron microscopy and in terms of surface chemistry by means of Fourier Transform Infrared Spectroscopy (FT-IR) exploiting attenuated total reflectance (ATR) geometry. The structure and the chemical properties of the different coatings were investigated by means of FT-IR. The characterization of the different protective coatings was carried out bymeans of electrochemical impedance spectroscopy measurements and potentiodynamic curves. [ABSTRACT FROM AUTHOR]

Friction StirWelding (FSW) is a solid-state welding process used for welding similar and dissimilar materials. FSW is especially suitable to join sheet Al alloys, and this technique allows different material couples to be welded continuously. In this study, 1050 Al alloys and commercially pure Cu were produced at three different tool rotation speeds (630, 1330, 2440 rpm) and three different tool traverse speeds (20, 30, 50 mm/min) with four different tool position (0, 1, 1.5, 2 mm) by friction stir welding. The influence of the welding parameters on the microstructure and mechanical properties of the joints was investigated. Tensile and bending tests and microhardness measurements were used to determine the mechanical properties. The microstructures of the weld zone were investigated by optical microscope and scanning electron microscope (SEM) and were analyzed in an energy dispersed spectrometer (EDS). Intermetallic phases were detected based on the X-ray diffraction (XRD) analysis results that evaluated the formation of phases in the weld zone. When the welding performance of the friction stir welded butt joints was evaluated, the maximum value obtained was 89.55% with a 1330 rpm tool rotational speed, 20 mm/min traverse speed and a 1 mm tool position configuration. The higher tensile strength is attributed to the dispersion strengthening of the fine Cu particles distributed over the Al material in the stir zone region. [ABSTRACT FROM AUTHOR]

Abstract: 1050 Aluminum alloy sheets were used to analyze the influence of a surface treatment on the characteristics of the alumina layer formed in a two-step anodizing. The study was mainly focused on two pretreatment steps, electropolishing and acid etching, as well as on the intermediate stripping step. The pretreatment procedure was optimized by accounting for the chemical nature of the substrate, with the results indicating that additional pretreatment steps enhanced the self-ordered porous arrangement. The E–t curves recorded during the experiments demonstrated that the best alumina layers were obtained when the first barrier layer had a high resistance; i.e., a high anodizing potential. The application time of the stripping step was optimized to clean the surface from alumina remains, without damaging the aluminum substrate. By optimizing all of these experimental conditions, we were able to obtain porous anodic aluminum oxide layers displaying ordered domains several hundreds of nanometers in length. [Copyright &y& Elsevier]