Production Of Aluminum Alloys Research Articles

Industrialized Application of Rheo-HPDC Process for the Production of Large Thin-Walled Aluminum Alloy Parts

A simplified and efficient process, namely air-cooled stirring rod (ACSR), was proposed to prepare semisolid slurry of aluminum alloys. An advanced integrated rheological high pressure die-casting (Rheo-HPDC) technology was established by combining the ACSR equipment with HPDC machines to produce high quality aluminum alloy products. Microstructures, surface qualities, mechanical properties, corrosion resistances and thermal conductivities of the Al-8Si alloy parts prepared by Rheo-HPDC were investigated and compared to those prepared by traditional HPDC. The results indicated that the Rheo-HPDC process can prepare aluminum alloy parts in which the primary particles are fine and spherical, and there is few shrinkage porosity. Multifarious high quality large thin-walled aluminum alloy parts, such as filter shells, cooling shells, antenna crates and mounting brackets for communication, were produced by the process. Rheo-HPDC alloys showed improved surface quality to those formed by traditional HPDC, and the surface roughness is small and avoid employing CNC to surface finish. Also, compared with HPDC alloys, the alloys prepared by Rheo-HPDC have an increased mechanical properties and thermal conductivity due to high density and refined microstructure. Furthermore, Rheo-HPDC aluminum alloys indicated a remarkable improvement in corrosion resistance as shown by the results of electrochemical and weight loss experiments.

Gravity Casting Of Variable Composition Al Alloys: Innovation And New Potentialities

Aluminum alloys are the most employed light alloys in the automotive sector. Therefore, aluminum-alloy production process must be flexible and competitive in order to meet the market needs. This study analyzes an innovative production process for aluminum alloys that can be employed for engine components like pistons. This kind of engine parts are typically subjected in service to high temperatures and fatigue stresses. The aim of this work is to define a sequential casting process for the production of a Functionally Graded Material (FGM) component with high-temperature resistance and ductility. The employ of two distinct aluminum alloys is at issue

Evaluation of the Temperature Regime of the Rods of the Inductor of an MHD Stirrer for Possible Use in an Industrial Aluminum Furnace

In the production of aluminum alloys, the melt must be stirred in the bath of a furnace. For this purpose, it is convenient to use MHD stirrers. However, MHD stirrers that are used in production in practice are mainly linear traveling-field inductors, which cannot be sufficiently effective because of their design features. Their size is much smaller than the linear dimensions of the bath, and the poles of their magnetic circuits are outside the bath walls and the insulation layer; therefore, the traveling magnetic field that influences the molten metal is significantly reduced. For this reason, the electrical power consumed by these MHD stirrers is high (hundreds of kilovolt–amperes). A device in the form of a system of rods (buses) connected in parallel to a three-phase power network and placed in close proximity to the molten metal immediately under the bottom of the bath may be an alternative to these stirrers. The main problem associated with this device is the cooling of rods via the removal of the Joule heat that is released during the passage of an electric current in the rods and the heat received from the molten metal in the bath in the furnace. The simplest way to withdraw the released heat is the convective movement of air in the tubular rods (it is not necessary to use special additional equipment). When conducting multivariant engineering calculations in designing such devices, it is necessary to determine the values of a cooling convective air flow in the hollow rods of the inductor of an MHD stirrer. In the present paper, we propose a numerical calculation of the temperature field in the aluminum furnace and a simple model for the convective air flow that passes through the rods of the inductor of an MHD stirrer. Based on this model and using the results of the physical experiments performed in this study, a simple semiempirical engineering formula for the approximate computation of the convective air-motion velocity in the hollow rods of an MHD stirrer is derived.

Recycling of LM25 aluminum alloy scraps

Abstract These days, a lot of metal scraps are generated by the automobile industry since the use of vehicles is increasing globally. As the production of automobile increases, the use of aluminum alloys has been increasing in automobile applications. Since the resources for the production of primary aluminum are getting scarce and the production of primary aluminum is highly expensive, production of components using secondary aluminum alloy in the form of scraps is highly essential. The present study deals with the re-melting of aluminium alloy scraps and the production of secondary aluminum alloy through a gravity die casting process. An investigation of its microstructure, chemical composition and mechanical properties such as hardness, tensile strength and an impact test have been performed and compared with the properties of primary and standard aluminum alloy. Porosity of secondary aluminum alloy is observed macroscopically. In addition a radiograph test was performed to study the internal defects of the secondary aluminum alloy.

Combined methods for the production of aluminum alloys

Combined methods for the production of aluminum alloys

Effect of Heat Treatment Combined with High Pressure Torsion Process on Microstructure and Hardness of AlMg5Si2Mn Alloy

This study evaluated the effect of a heat treatment on the potential application of AlMg5Si2Mn die casting alloy as a substitute for wrought aluminium alloy products. The proposed heat treatment was intended to increase the workability of the AlMg5Si2Mn alloy, which is typically not malleable due to the presence of interconnected brittle phases. By disintegrating interconnected eutectic Mg2Si phases into fragmented particles and dissolving Mg-rich phases the workability was increased. Subsequently, heat treated samples were subjected to high-pressure torsion process. The microstructure of the heat treated and deformed samples were characterized using light and electron microscope. Hardness measurements were used to investigate the influence the number of HPT revolutions on mechanical properties.

Study on Simulation of Stamping Forming and Die Surface Optimization of Aluminum Alloy Plate

Along with the automobile lightweight development, aluminum has become the focus of its own material characteristics. The aluminum alloy products with high efficiency, high quality and low cost are the guarantee of competitive advantage. High quality die surface is directly related to the product quality, cost, production efficiency, die life and so on. In this paper, the stamping process of two kinds of aluminum alloy products was simulated by Auto Form. The method of setting blank holding force and spring back compensation was introduced. At the same time, the setting of parameters such as die fillet, friction coefficient and draw bead was described in this paper. Finally, the optimization of die surface design was achieved by simulation.

Producing aluminum alloy / copper alloy dissimilar materials joint plate by using friction stir welding

Producing aluminum alloy / copper alloy dissimilar materials joint plate by using friction stir welding

Production and Mechanical Testing of Aluminium Alloy Based Hybrid Metal Matrix Composite

The present work aims for uniformly dispersing Aluminium Oxide (Al2O3) and Graphite (Gr) particulates in an Aluminium Alloy Matrix to produce a hybrid composite and then to carry out the investigation and analysis of mechanical properties of developed composite. The particle size of Al2O3 and Gr were less than 45 microns. The stir casting technique is utilized to produce the hybrid composite having 2% Al2O3 with 0.5%, 1% Gr and 4% Al2O3 with 0.5%, 1% Gr. The composites were studied for density changes due to reinforcements, hardness, tensile strength and wear behaviour in Non-Heat Treated (NHT) conditions. The tests were done at the laboratory conditions as per ASTM guidelines. The Pin-On-Disc machine is used to test the sliding wear behaviour under dry conditions. The measured density is found to be decreasing as the reinforcement quantity is increased. The as cast Al alloy was found to be having highest hardness and the composites with increasing Gr exhibited lower hardness. The composite tensile strength is observed to be decreased in comparison to base alloy due to the presence of Gr but composite having highest quantity of Gr showed superior wear resistance which is mainly because the Gr particulates provide an inherent lubricating properties to composite. The composites developed in the present work can be used in the automobile and aerospace parts that are light in weight and require self-lubricating properties to enhance the wear resistance.

Fabrication and Performance Test of Aluminium Alloy-Rice Husk Ash Hybrid Metal Matrix Composite as Industrial and Construction Material

Aluminium matrix composites (AMCs) used extensively in various engineering fields due to their exceptional mechanical properties. In this present study, aluminium matrix composites (AMCs) such as aluminium alloy (A356) reinforced with rice husk ash particles (RHA) are made to explore the possibilities of reinforcing aluminium alloy. The stir casting method was applied to produce aluminium alloy (A356) reinforced with various amounts of (2%, 4%, and 6%) rice husk ash (RHA) particles. Physical treatment was carried out before the rice husk ash manufacturing process. The effect of mechanical strength of the fabricated hybrid composite was investigated. Therefore, impact test, tensile stress, compressive stress, and some other tests were carried out to analyse the mechanical properties. From the experimental results, it was found that maximum tensile, and compressive stress were found at 6% rice husk ash (RHA) and aluminium matrix composites (AMCs). In future, the optimum percentages of rice husk ash (RHA) to fabricate the hybrid composites will be determined. Also, simulation by finite element method (FEM) will be applied for further investigation.

Mechanical Alloying of Secondary Raw Material for Foam Aluminum Production

Interest in developing new compositions and technology for preparing foam aluminum is explained by the existence for objects of this material of an unusual set of properties: low density, low thermal and electrical conductivity, good resistance to the action of fire, ecological cleanliness, and capacity to absorb impact energy effectively. Foam aluminum is prepared by liquid- and solid-phase methods, and mainly from primary materials, which is quite expensive. One of the solid phase (or powder) methods is mechanical alloying, which is a most promising direction for composite material production. This is one of the most contemporary methods for preparing precipitation hardening ceramic particles of composite materials based on nonferrous metals. Foam aluminum may be considered as a composite where instead of ceramic particles there are particles of porofor TiH2. Therefore, mechanical alloying may also be considered as a promising method for its preparation. The method includes treatment of powder components and their mixtures in high-energy mills followed by consolidation of a uniform activated mixture in order to prepare a semiproduct or finished component. Another advantage of mechanical alloying is the possibility of using aluminum alloy production waste, which significantly cheapens production (raw material component in the cost of production is reduced by 45–65%). Results are provided for studying the process of modeling and development of technology for preparing foam aluminum from aluminum secondary raw material.

Investigation of corrosion resistance of aluminum alloy products with protective coatings formed by plasma electrolytic oxidation

A methodology for determining the duration of destruction of oxide ceramic coatings is suggested. The coatings were formed on aluminum alloys by plasma electrolytic oxidation (PEO) under the pressure of the corrosion products of the metal substrate. The experimental results that confirm the proposed theoretical description are presented. The studies were performed in a laboratory autoclave according to GOST (State Standard) 9.308. Application of the method makes it possible to predict how long the coatings formed by PEO will last in aggressive media before their destruction.

Influence of temperatures of melt overheating and pouring on the quality of aluminum alloy lost foam castings

Lost foam casting (LFC) is currently one of the most efficient and promising methods of fabricating high-quality thin-wall castings possessing specified dimensional accuracy, required surface roughness, and other properties. This technology is widely used in the production of aluminum alloy products. To minimize costs in the fabrication of wares and to fabricate high-quality castings, it is reasonable to use an increased amount of secondary materials in the charge, herewith paying attention to the melt overheating temperature and holding time. The results of studying the temperature modes of smelting pouring aluminum alloys in the LFC are presented. The most efficient modes in manufacturing conditions under consideration which provide the best quality characteristics of leak-tight castings by dimensional accuracy and surface roughness were as follows: the melt overheating temperature is 880–890°C and the melt pouring temperature into the casting mold is 820–830°C. The influence of various variants of temperature parameters of smelting and pouring the melt of the AK7 composition during the LFC on the content of nonmetallic inclusions in the cast state is investigated. It is revealed that the minimal γ-Al2O3 content in the final alloy is provided by a melt overheating temperature of up to 880–890 or 940–950°C and a melt pouring temperature into the casting mold of 820–830°C.

Eco-efficient lightweight carbon-fiber reinforced polymer for environmentally greener commercial aviation industry

This research aims to perform comparative impact assessment for production of conventional aluminum alloy (AlMg3) used in aircraft fuselage and lighter weight carbon-fiber reinforced polymer (CFRP). The epoxy resin (EP), a thermosetting polymer typically impregnated with carbon fiber (CF) tows is assumed to be replaced by polypropylene (PP) which is a thermoplastic polymer. The assessment framework is demonstrated by postulating a scenario where AlMg3 in Boeing B737-800 fuselage is substituted with CFRP to reduce the fuselage weight by about 4.3 tons. OpenLCA 1.4.2 platform, including Ecoinvent v2.2 life cycle inventory (LCI) database and TRACE 2.1 methodology for life cycle impact assessment (LCIA), is used to quantify and compare mid-point impact categories of the AlMg3-based scenario and the postulated base case scenario using CFRP (53.8 wt% CF). The CF content in CFRP is used as a sensitivity parameter for impact categories calculations. The assessment results showed that AlMg3-based scenario leads to higher impact categories compared to the postulated CFRP (53.8 wt% CF) base case scenario. Additionally, results of the performed scenario analysis show ≈ 42% reduction in energy intensity associated with the high-volume CFRP production (base case scenario) compared to the low-volume production scenario. All calculated impact categories associated with the low-volume production scenario exceed the corresponding impact categories associated with the high-volume production (base case scenario). For example, ozone depletion potential (ODP) for the low-volume production scenario is ≈ 20.7% higher than that of the high-volume production scenario and global warming potential (GWP) for the low-volume production scenario is ≈10.2% higher than that of the high-volume production scenario. This research also compares impact categories associated with recycled CF (rCF) from end-of-life (EOL) CFRP (with PP resin matrix) to those corresponding to rCF from EOL-CFRP (with EP resin matrix). Overall, the results of this research support its alternative hypothesis (H1) which claims that replacing PE with PP in CFRP reduces the energy intensity and LCIA impact categories associated with CFRP production as well as rCF from EOL-CFRP. Finally, replacing fuselage’s AlMg3 with CFRP in Boeing’s new aircraft fleet by 2035 (Boeing Market Outlook 2016–2035) will lead to an estimated global carbon footprint reduction of ≈ 1x106 tons CO2 eq. Future global commercial aircraft could adopt the insights of this contribution to shrink their carbon footprint.

Twin Roll Casting of Aluminium Alloy ADC12, A3003, A7075

This paper describes a vertical type twin roll strip casting process for producing aluminum alloy strip of ADC12, A3003 and A7075. Twin roll casting process is able to produce a strip from molten metal directly. Thus this process has a possibility to reduce total cost of sheet making comparing to conventional rolling process. Aluminum alloy ADC12 is a casting material that is used for die casting. A3003 is known as a wrought aluminum alloy for aluminum can body sheet. The A3003 sheet is generally produced by rolling, so it is effective for reducing a process cost to produce the strip by twin roll casting process. Aluminum alloy A7075 has high tensile strength, and it is known as a material for aerospace application. The sheet is manufactured in small quantities comparing to the other sheet aluminum alloy. It is supposed that the demand of high tensile strength aluminum sheet such as A7075 is going to increase for weight saving of structural material. In this study, twin roll casting experiment was performed to produce these three aluminum alloy strip in same experimental conditions. Castability, surface conditions and strip thickness were estimated. It was possible to cast these aluminum alloy strip.

RECYCLING AND PROPERTIES OF RECYCLED ALUMINIUM ALLOYS USED IN THE TRANSPORTATION INDUSTRY

Summary. Nowadays, a transportation industry creates a lot of metal scrap because production and use of cars are on the increase worldwide. This is based on the fact that increase in the production of cars increases usage of aluminium alloys in transportation applications. Therefore, it is necessary to reduce the production of components from primary aluminium alloy and increase their replacement with secondary—recycled— aluminium alloys because the production of recycled aluminium alloys is less expensive and less energy-intensive than the creation of new aluminium alloy through the electrolysis. In addition, the recycled aluminium alloys have comparable microstructural parameters and properties as the same primary aluminium alloys.

Horizontal twin roll casting of aluminum alloy A5052

This paper describes a horizontal type twin roll strip casting process for producing aluminum alloy strip of A5052. Twin roll casting process is able to produce a strip from molten metal directly. Thus this process has a possibility to reduce total cost of sheet making comparing to conventional rolling process. Strip casting process has some disadvantages. Casting speed depends on the material properties. It is difficult to determine the casting conditions. A 5052 is a typical alloy showing moderate strength among aluminum alloys. It is known as the alloy most frequently used for sheet among aluminum alloys. Because it has relatively high strength, excellent corrosion resistance, castability and weldability, it is used not only as a can lid material but also as a structural member of a vehicle and ship. In this study, the effect of pouring temperature was investigated. Castability, surface conditions and strip thickness were estimated. It was possible to produce strip at different pouring temperature by horizontal twin roll strip casting process. Each surfaces of produced strip were transcribed form the roll surface, and the surfaces had a metallic luster.

Temperature Prediction of Aluminum Alloy Work-Pieces in Aging Furnaces Based on Improved Case-Based Reasoning

The temperature of aluminum alloy work-pieces in the aging furnace directly affects the quality of aluminum alloy products. Since the temperature of aluminum alloy work-pieces cannot be measured directly, a temperature prediction model based on improved case-based reasoning (CBR) method is established to realize the online measurement of the work-pieces temperature. More specifically, the model is constructed by an advanced case-based reasoning method in which a state transition algorithm (STA) is firstly used to optimize the weights of feature attributes. In other words, STA is utilized to find the suitable attribute weights of the CBR model that can improve the accuracy of the case retrieval process. Finally, the CBR model based on STA (STCBR) was applied to predict the temperature of aluminum alloy work-pieces in the aging furnace. The results of the experiments indicated that the developed model can realize high-accuracy prediction of work-pieces temperature and it has good application prospects in the industrial field.

ANÁLISIS CUANTITATIVO DE LOS ELEMENTOS ALEANTES PRINCIPALES PRECIPITADOS EN BILLETS DE ALUMINIO DE ALEACIÓN 6063 EN EQUIPO DE FUNDICIÓN DE COLADA CONTINUA HORIZONTAL PARA EL PROCESO DE EXTRUSIÓN

<p>La escasez de estudios <em>in situ</em> sobre procesos de colada continua horizontal en aleaciones de aluminio, impulsa la necesidad de investigar la influencia de temperatura, velocidad y materia prima en <em>billets</em> de aluminio homogenizados AA6063. Aplicando ensayos de espectrometría, permiten cuantificar el porcentaje en peso de aleantes principales magnesio y silicio. Estos elementos al precipitar forman siliciuro de magnesio (Mg<sub>2</sub>Si) durante el proceso de homogenizado. Para este estudio se produjo <em>billets</em> de aleación normal y experimental, demostrando una relación inversa entre los niveles de siliciuro de magnesio y dureza Brinell; así también la influencia de bajos niveles de porcentaje en peso de Mg<sub>2</sub>Si en la reducción de la resistencia a la tracción en el material.</p>

Application of Vertical-Type High-Speed Twin-Roll Casting for Up-Grade Recycling and Clad Sheets Fabrication of Aluminum Alloys

A horizontal-type twin roll casting method has been popular for producing aluminum alloy strips, however, it is characterized by a relatively low productivity (1~6 m/min). In contrast, a vertical-type high-speed twin-roll casting method possesses an extremely high productivity (60~120 m/min (1~2 m/s)) and an excellent heat extraction ability. The rapid cooling effect provided significant microstructure refinement and mechanical properties improvement in various kinds of cast aluminum alloy products. Not only “product to product recycling” but also “up-grade recycling” can be achieved by making good use of these merits. Two examples of application showing the potential of vertical-type high-speed twin roll casting method are presented. (1) Several kinds of Al-Si base alloy were cast into the strips. Not only strength and toughness but also formability was increased in the twin roll cast products. In particular, great improvement in deformability shows the potential of the twin-roll cast aluminum alloy products as substitutes for some wrought aluminum alloy products. (2) The vertical-type tandem twin-roll caster was able to fabricate a clad strip by single step. The A4045/A3003/A4045 aluminum alloy clad sheets produced by the twin-roll casting showed better mechanical properties than the conventional hot-roll bonded clad sheets.