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.
•Time- and cost-efficient estimation of fatigue strength of aluminum profiles.•Application of continuous cyclic load increase procedure.•Qualification of solid-state recycled aluminum chip ...profiles.•Mechanism-related differences in cyclic deformation and creep behavior.•Fractographic correlation of results of load increase tests and creep behavior.
Because of the great potential to reduce the amount of energy, the direct recycling of scrap like aluminum chips by hot extrusion is a hopeful alternative to the usual remelting process. Previous investigations showed that the chips, which are encased by oxide layers, are elongated due to the extrusion process. Therefore, the aim of this study is to test to what extend anisotropic properties, in analogy to fiber-reinforced materials, can be determined. The mechanical properties of cast-based and chip-based specimens with orientations of 0°, 30° and 90° to extrusion direction were characterized by means of mechanical quasistatic and cyclic experiments. It could be shown that quasistatic properties of the 0° orientation are highest for chip-based specimens, whereby the differences to the other orientations are slight. On the other hand, large differences in cyclic creep behavior between the orientations as well as in damage behavior could be determined.
The melt conditioned direct chill (MC-DC) casting process has been used to produce billets and extruded planks of AA5754 alloy formulated from 100% recycled Taint Tabor scrap aluminum. The billets ...were homogenized and then extruded into flat planks. Optical metallography of the MC-DC cast billets showed equiaxed refined grains in comparison to conventional direct chill (DC) cast and direct chill grain refined (DC-GR) cast billets formulated from the same Taint Tabor scrap. Microstructural evaluation of the extruded planks showed extensive peripheral coarse grain (PCG) for the DC, DC-GR and MC-DC cast planks. The 2 mm and 1 mm MC-DC cast planks produced after cold rolling and heat treatment showed a fully recrystallized microstructure at 380 °C and 300 °C for 10 min respectively with an improvement in mechanical properties over DC-GR cast and similarly processed planks. The as-extruded MC-DC cast planks tensile tested in the transverse direction showed 34% elongation and 213 MPa ultimate tensile strength. These tensile results showed 5.8% higher elongation and 1.2% higher ultimate tensile strength compared with the DC-GR planks after applying high shear melt conditioning.
The removability of impurities during the aluminum remelting process by oxidation was previously investigated by our research group. In the present work, alternative impurity removal with ...chlorination has been evaluated by thermodynamic analysis. For 43 different elements, equilibrium distribution ratios among metal, chloride flux and oxide slag phases in the aluminum remelting process were calculated by assuming the binary systems of aluminum and an impurity element. It was found that the removability of impurities isn't significantly affected by process parameters such as chloride partial pressure, temperature and flux composition. It was shown that Ho, Dy, Li, La, Mg, Gd, Ce, Yb, Ca and Sr can be potentially eliminated into flux by chlorination from the remelted aluminum. Chlorination and oxidation are not effective to remove other impurities from the melting aluminum, due to the limited parameters which can be controlled during the remelting process. It follows that a proper management of aluminum scrap such as sorting based on the composition of the products is important for sustainable aluminum recycling.
This paper describes calculations using the mass balance method on aluminum alloy scraps, including soft drink cans, aluminum engine components, low alloy aluminum materials, and aluminum computer ...disks, to formulate A380.0 casting alloy. All recycled aluminum alloys from the same source were considered to be identical. Six approaches of mixing by weight percent, with the aid of an X-ray fluorescence technique, were successfully completed. A380.0 electrical conduit fittings were produced using the die casting technique. Mechanical tests including compression, impact, tensile, and suspended load indicated that die cast recycled aluminum alloy conduit fittings under classification 4 (heavy load condition) satisfied the requirements as stated in BSEN 50086-1: 1993.
The recycling link between End-of-Life (EoL) product composition and metallurgical recovery is discussed in this chapter with reference to a materials centric view (aluminium, copper) and product ...centric by referring to products such as End-of-Life Vehicles, WEEE, E-waste, Lighting, TV/Displays and Catalysts, Batteries etc. For each of the EoL metals and products, some detail of “mineralogy,” i.e. composition, of each product type is provided also referring to Critical raw materials and recyclate quality. Then recycling in terms of collection and physical as well as metallurgical separation is discussed in some detail. In order to capture the whole cycle, process and system simulation is discussed with reference to various existing tools, also showing various simulation results. Finally, physics-based eco-labeling is discussed while also referring to design for recycling (DfR). 10 Design for Recycling rules are also provided as a function of the detail discussed in this chapter.
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