Advanced Aluminum Alloys Research Articles

Development of Advanced Aluminum and Magnesium Alloys: Microstructure, Mechanical Properties and Processing

Mg and Al alloys are the first and second engineering light metals, which are widely used in the aviation, aerospace, navigation, automotive, and electronic fields [...]

A Quantitative Phase Analysis by Neutron Diffraction of Conventional and Advanced Aluminum Alloys Thermally Conditioned for Elevated-Temperature Applications.

As the issue of climate change becomes more prevalent, engineers have focused on developing lightweight Al alloys capable of increasing the power density of powertrains. The characterization of these alloys has been focused on mechanical properties and less on the fundamental response of microstructures to achieve these properties. Therefore, this study assesses the quality of the microstructure of two high-temperature Al alloys (A356 + 3.5RE and Al-8Ce-10Mg), comparing them to T6 A356. These alloys underwent thermal conditioning at 250 and 300 °C for 200 h. Time-of-flight neutron diffraction experiments were performed before and after conditioning. The phase evolution was quantified using Rietveld refinement. It was found that the Si phase grows significantly (13-24%) in T6 A356, A356 + 3.5RE, and T6 A356 + 3.5RE alloys, which is typically correlated with a reduction in mechanical properties. Subjecting the A356 3.5RE alloy to a T6 heat treatment stabilizes the orthorhombic Al4Ce3Si6 and monoclinic β-Al5FeSi phases, making them resistant to thermal conditioning. These two phases are known for enhancing mechanical properties. Additionally, the T6 treatment reduced the vol.% of the cubic Al20CeTi2 and hexagonal ᴨ-Al9FeSi3Mg5 phases by 13% and 23%, respectively. These phases have detrimental mechanical properties. The Al-8Ce-10Mg alloy cubic β-Al3Mg2 phase showed significant growth (82-101%) in response to conditioning, while the orthorhombic Al11Ce3 phase remained stable. The growth of the beta phase is known to decrease the mechanical properties of this alloy. These efforts give valuable insight into how these alloys will perform and evolve in demanding high-temperature environments.

Experimental Investigation into the Preparation Process of Graphene-Reinforced Aluminum Matrix Composites by Friction Stirring Processing.

Graphene has been considered an ideal reinforcement in aluminum alloys with its high Young's modulus and fracture strength, which greatly expands the application range of aluminum alloys. However, the dispersion of graphene and the interfacial reaction between graphene and the aluminum matrix limit its application due to elevated temperature. Friction stirring processing (FSP) is regarded as a promising technique to prepare metal matrix composites at lower temperatures. In this paper, FSP was used to prepare graphene-nanoplates-reinforced aluminum composites (GNPs/Al). The corresponding effects of the process parameters and graphene content on GNPs/Al were thoroughly studied. The results showed that plastic strain, heat input, and graphene content were the key influencing factors. Large degrees of plastic strain can enhance the dispersion of graphene by increasing the number of stirring passes and the ratio of stirring to welding velocity, thereby improving the strength of GNPs/Al. Low heat input restricts the plastic flow of graphene in the matrix, whereas excessive heat input can promote interfacial reactions and lead to the formation of a more brittle phase, Al4C3. This is primarily associated with the stirring velocity and welding velocity. High graphene content levels can improve the material strength by refining the grain size, improving the load transfer ability, and acting as a precipitate to prevent dislocation movement. These findings make a contribution to the development of advanced aluminum alloys with graphene reinforcement, offering broader application potential in industries.

Unraveling the leverage effect in phases stability and mechanical properties of Al-Zn-Mg-Cu alloy

In order to further improve the comprehensive performance of advanced aluminum (Al) alloys, especially 7xxx Al-Zn-Mg-Cu alloys, tuning the relative ratios between major alloying elements (Zn, Mg, Cu) while maintaining the total alloying amount has been widely adopted. However, the specific influence of these relative element ratios on various properties has yet to be well understood. In this work, the leverage effect of those alloying element pairs (Al:Cu, Mg:Zn, Cu:Mg, and Cu:Zn) on the phase stability and mechanical properties of Al-Zn-Mg-Cu alloy is systematically investigated by means of first-principles calculations, cluster expansion, and quasi-harmonic Debye model. The tradeoffs in formation energy, elastic strength, and anisotropy are unraveled when the element pairs deviate from the equal ratio (1:1), indicating a strong leverage effect in element pairs. Among those element pairs, Al:Cu and Cu:Mg are the major lever in phase stability, in which the stable phase reversed on the two sides of 1:1; while the Mg:Zn lever dominates the elastic strength and anisotropy. Cu:Zn, on the other hand, has less impact on material properties. The underlying mechanism of those leverage effect is analyzed by the bonding electron density and lattice distortion around the major alloying elements. Our results are in good agreement with experimental observations and clarify the controversaries of those element pairs on the material properties. The weight of each lever could provide a practical guidance to the optimization of the alloy composition of 7xxx Al-Zn-Mg-Cu alloys, and also shed lights on the development of other advanced alloy systems.

Optimization Process Parameters in Testing of Wear properties of Aluminium Alloy 6082

When the two materials are in contact in motion, wear rate of the materials taken an important role. Aluminium alloys used in many applications like automobile components, aerospace components, home appliances, machine tool components. Advanced aluminium alloys are used in aerospace components. In this project wear studies of advanced aluminium alloys are carried using pin-on-disc machine three processing parameters considered are Load, Time and Speed. Twenty seven samples ae been tested to find wear rate of aluminium alloys. A Taguchi method is applied to find optimization process parameters which are having minimum wear rate. Aluminium alloy 6082 has a medium strength and good corrosion resistance. It is the strongest alloy

Prediction of weld area based on image recognition and machine learning in laser oscillation welding of aluminum alloy

Laser oscillation welding is an advanced aluminum alloy welding technology which can effectively reduce weld porosity induced by physical and chemical properties of aluminum alloy. Weld area is often as an evaluation index of geometric characteristics to evaluate the welding quality since it has great effect on the mechanical properties of welded joints. In this paper, a prediction method of weld area based on process parameters is proposed for laser oscillation welding of 6061 aluminum alloy. From the metallographic micrographs of welding experiments, the cross-sectional area of weld is calculated by image recognition technology and the error of recognized weld area is less than 8.8%. Additionally, various prediction models for weld area under different process conditions are established by machine learning algorithms including linear regression, polynomial regression and back propagation neural network (BPNN). The established prediction models are compared by the mean square error (MSE) and coefficient of determination (R2). The results show that the BPNN prediction model indicates the highest accuracy and robustnessand can be adopted to predict the cross-sectional area of weld. The proposed method can be used for selecting the optimal process condition for the ideal welded joints with the desired weld geometry to improve the quality of laser oscillation welding.

Metal additive manufacturing of commercial aerospace components – A comprehensive review

Metal additive manufacturing (AM) has matured and grown from its infancy in the research stage to the fabrication of new and advanced components for its supreme applications. AM is a lead for the advanced manufacturing processes with an increased and advanced potential to revolutionize the manufacturing domain. It could exhibit a progressive change in the project and design paradigms. In the past decade, the use of metal AM process in the aerospace industry to build, repair various components for military applications and several outer space vehicle fabrications have occupied higher potential among various other manufacturing industries. In addition to it, many studies have made it a more versatile, common, and safer technology for the design and fabrication of components with the introduction of novel processes, materials, technologies, cost efficiency, and process design. In the present review article, the use of advanced aluminum alloys in the AM of fuselage, horizontal stabilizer, and high and low wings has gained increased advantages in the aerospace industry. Various components of wings and fuselage with its merits and demerits in AM processing are discussed. The outstanding issues in AM process and steps to overcome with post-processing techniques are elaborated. Finally, the future scope and research directions of the AM process involved in the fabrication of selected components are discussed.

Selective laser melting of AlCu-TiB2 alloy using pulsed wave laser emission mode: processability, microstructure and mechanical properties

The present work explores the processability of an advanced aluminum alloy, namely AlCu-TiB2, by selective laser melting (SLM), and the correlation between microstructure and mechanical properties of as built specimens. The principal process parameters of the laser emission in pulsed wave (PW) mode, namely laser power and exposure time, were varied to achieve full density parts starting from prealloyed powders. Detailed analysis of defects in the highest relative density conditions was performed thzrough X-ray computed tomography. It was found that the highest relative density, up to 99.5%, was achieved at a laser energy density of 82 J/mm3. Microstructure of as-built specimens was analyzed through scanning electron microscopy, coupled with EDX and EBSD analyses, and transmission electron microscopy. The as-built microstructure was considerably uniform, and characterized by fine equiaxed grains, decorated with micrometric and nanometric second phases and an even distribution of reinforcing TiB2 particles; no epitaxial grain growth was observed. Finally, tensile behaviour of the as-built specimens indicates a yield and ultimate tensile stress of 325 MPa and 395 MPa, respectively, combined with an elongation of 13%. The low work hardening rate and jerky flow characterizing plastic deformation are analyzed and discussed.

Correlation of CFRP and AA7075 Aircraft Wing box structure using FEM

Composite materials are becoming more important in the construction of Mechanical structures. The primary objective of this paper is to analyse the Carbon Fibre Reinforced Plastic (CFRP) and Aluminium alloy (AA 7075) aircraft wing box using finite element method. Both results has been correlated. Both CFRP and AA7075 structures modelling and numerical simulations were executed at various loading conditions. The deformed configuration of the CFRP and AA7075 aircraft wing box along with stress plot have been computed using analysis. Based on these studies, the CFRP and AA7075 central wing box, representing a weight saving of up to one and a half tonnes compared to the most advanced aluminium alloys. The results also expose the increasing strength with reduced weight.

Evaluation of Advanced Aluminum Alloys for Use in New-Generation Wires

Evaluation of Advanced Aluminum Alloys for Use in New-Generation Wires

The processing route towards outstanding performance of the severely deformed Al–Mg–Mn-Sc-Zr alloy

Abstract Aiming at obtaining the enhanced mechanical properties profile for lightweight applications, bulk billets of the commercial 1570C aluminium alloy (Al–5Mg-0.18Mn-0.20Sc-0.08Zr, wt. %) with nanosized aluminides of transition metals (TM) were subjected to various thermomechanical treatments comprising severe plastic deformation for grain refinement and favourable distribution of disperse phases. The potential of multiaxial isothermal forging (MIF) for the fabrication of ultrafine-grain advanced aluminium alloys is unveiled via a multistep pathway involving two primary routes – the one under constant processing temperature and the other with the inter-step temperature reduction from 325 to 175 °C - combined with conventional cold rolling or high-pressure torsion. Processing-dependent microstructural factors controlling the alloy's behaviour under monotonic and cyclic loading at ambient temperature are discussed with the account of the role of the grain size, grain boundary distribution, precipitates of Mg-rich β-phase and TM-aluminides. In particular, it is shown that after MIF followed by cold rolling, the outstanding combination of the tensile strength and ductility was observed concomitantly with the fatigue resistance superior to that in the contemporary alloys of the same class and/or of many currently available commercial high-strength alloys.

Advanced aluminum alloys for aircraft brazed structures

Review of domestic and foreign scientific and technical literature in the fi eld of application of aluminum alloys for brazed structures of aircraft heat exchangers manufactured by high-temperature vacuum brazing is provided. Prospective developments of domestic aluminum alloys for application as base material for clad sheets for brazed structures of heat exchangers are presented. The possibilities for increasing of the corrosion resistance of heat transfer surfaces are considered. The possibilities for application of additive technologies for the manufacture of aluminum heat exchangers alloys are considered.

Structure and mechanical properties of an advanced aluminium alloy AlSi10MgCu(Ce,Zr) produced by selective laser melting

The article presents investigation of structure and mechanical properties of an advanced aluminum alloy Al-10Si-0.9Cu-0.7 Mg-0.3Zr-0.3Ce, produced by selective laser melting. By means of SEM, TEM and EDX-analysis some aspects of the alloy microstructure in as-built and thermal treated states are discussed. The alloy has high level of strength (UTS > 390 MPa, YS > 330 MPa) in T6-state, providing good elongation (El. > 6%). In annealed state the alloy also provides good combination of mechanical properties (UTS > 350 MPa, YS > 240 MPa, El. > 9%).

Modifying microstructures and mechanical properties of laser-arc welded joints of dissimilar advanced aluminum alloys

In this paper, two dissimilar aluminum alloys (AA), AA5083 and AA6082, have been joined via fiber laser-MIG welding method using two different filling wires (ER4043 and ER5356). The heat input for producing joints with ER5356 and ER4043 is respectively 289.36 J/mm and 293.38 J/mm. The microstructures are characterized from testing of SEM, EDS and EBSD. Results show that joints using ER4043 wire (referred as ER4 joints) have finer microstructures in terms of smaller grain size (49 ± 63 μm) and higher dislocation density (1.25 × 1013 m−2). The average microhardness in fusion zone (FZ) of ER4 joints is 82 HV, which is greater than that of joints using ER5356 wire (referred as ER5 joints). However, the ultimate tensile strength (UTS) of ER4 joints are weaker than that of ER5 joints, with the UTS of ER4 and ER5 joints being 220 MPa and 232 MPa, respectively. Strengthening mechanisms in these two types of joints are quantitatively presented via a strength model, which can well reproduce the yield strength of these two types of joints. With molecular dynamic simulation, it is revealed that the loss of mechanical properties of ER4 joints is caused by the high density of pores in its FZ, since these pores lead to serious stress concentration under external uniaxial loading.

Casting and Forming of Advanced Aluminum Alloys

The automotive and aeronautical industry´s response to the environmental impact provoked by gas emissions and consumer expectations has driven aluminum alloy casting changes in recent years [...]

How aluminum changed the world: A metallurgical revolution through technological and cultural perspectives

The history of aluminum is rather short since it was discovered only in the nineteenth century, yet it has become an important part of everyday life. This article reviews the history of aluminum through technological breakthroughs as well as from cultural and social perspectives, beginning with its discovery, through the nineteenth and twentieth centuries until today; and aims to suggest possible future trends and applications for aluminum alloys. Aluminum has a high strength-to-weight ratio combined with excellent thermal conductivity and good corrosion resistance. Therefore, aluminum is an attractive material for many applications, including transportation, electrical and packaging industries, architecture, and food industries. It is also a recyclable metal, which provides both environmental and economic advantages. The commercial use of aluminum started at the end of the nineteenth century and continues to grow today with the development of new advanced aluminum alloys. Consequently, from a cultural perspective, aluminum is considered a symbol of modernity. Technological breakthroughs generate economic growth and social benefits. Present applications of aluminum include new choices, such as 3D printing, composite materials, nano-rods, biomedicine devices and aerospace uses. Based on the excellent properties of aluminum, its low price, combined with its significant scrap value and a growing recycling market, as well as its accelerating global production, it is expected that the aluminum industries will considerably grow through the twenty-first century and aluminum will continue to be a major part of our everyday culture. Therefore, based on the increasing growth of aluminum production and consumption, additional research and development effort is needed in the following years to minimize the negative environmental side effects associated with the technological developments related to aluminum production and at the same time creating further technological innovation.

Sasol Chemicals expands alumina production capacity to meet growing market demand.

The history of aluminum is rather short since it was discovered only in the nineteenth century, yet it has become an important part of everyday life. This article reviews the history of aluminum through technological breakthroughs as well as from cultural and social perspectives, beginning with its discovery, through the nineteenth and twentieth centuries until today; and aims to suggest possible future trends and applications for aluminum alloys. Aluminum has a high strength-to-weight ratio combined with excellent thermal conductivity and good corrosion resistance. Therefore, aluminum is an attractive material for many applications, including transportation, electrical and packaging industries, architecture, and food industries. It is also a recyclable metal, which provides both environmental and economic advantages. The commercial use of aluminum started at the end of the nineteenth century and continues to grow today with the development of new advanced aluminum alloys. Consequently, from a cultural perspective, aluminum is considered a symbol of modernity. Technological breakthroughs generate economic growth and social benefits. Present applications of aluminum include new choices, such as 3D printing, composite materials, nano-rods, biomedicine devices and aerospace uses. Based on the excellent properties of aluminum, its low price, combined with its significant scrap value and a growing recycling market, as well as its accelerating global production, it is expected that the aluminum industries will considerably grow through the twenty-first century and aluminum will continue to be a major part of our everyday culture. Therefore, based on the increasing growth of aluminum production and consumption, additional research and development effort is needed in the following years to minimize the negative environmental side effects associated with the technological developments related to aluminum production and at the same time creating further technological innovation.

Development and Evaluation of an Advanced Aluminum Alloy for Additive Manufacturing

Development and Evaluation of an Advanced Aluminum Alloy for Additive Manufacturing

Validation of Kinematic Hardening Parameters from Different Stress States and Levels of Plastic Strain with the Use of the Cyclic Bending Test

The recent development of new lightweight sheet metal materials, like advanced high-strength steels or aluminium alloys, in combination with an increasing component complexity provides new challenges to the numerical material modelling in the FEM based process design. An auspicious approach to improve the quality of the numerical results – most notably in springback analysis – is the modelling of the so called Bauschinger effect achieved through implementation of kinematic hardening models. Within this paper the influence of the stress state and the level of pre-strain on the numerical simulation result of the advanced high strength steel DP-K45/78+Z will be analysed. For this purpose, a parameter identification of the kinematic hardening law according to Chaboche and Rousselier is performed at different pre-strains on the basis of experimental data from tension-compression tests as well as cyclic shear tests. Finally, the identified parameters are validated in a comparison between numerical and experimental results of a cyclic bending test.

Considering Anisotropic Material Behaviour of Sheet Metals for Ductile Fracture Prediction

In the manufacturing process of body in white components made from sheet metal it is state of the art to accompany the process by means of finite element analysis. A main criterion for determining a feasible tool design and process parameters is the prediction of material failure, which can be categorized in instability and ductile fracture. The ductile fracture failure mode is more likely to occur, as more advanced high strength steels and aluminium alloys are used for body in white components. Therefore various approaches have been presented to model ductile fracture over the past years. However, there is no guideline to determine which models are suitable for predicting ductile fracture. The same applies when it comes to choosing experiments and calibration of model parameters. A suitable model calibration is vital, as the fracture prediction depends on the determined model parameters. Usually an isotropic material behaviour is assumed for calibration of fracture models. However, sheet metals can show an anisotropic material behaviour due to the rolling process. Therefore it is arguable if an isotropic material model can be applied when fracture models are calibrated.