Direct Chill Casting and Extrusion of AA6111 Aluminum Alloy Formulated from Taint Tabor Scrap

AA6111 aluminum automotive body-sheet alloy has been formulated from 100% Taint Tabor scrap aluminum. Direct chill casting with and without high shear melt conditioning (HSMC) was used to produce the AA6111 alloy billets. Both homogenized and non-homogenized billets were extruded into sheets. The optical micrographs of the melt conditioned direct chill (MC-DC) samples showed refined equiaxed grains in comparison to direct chill (DC) cast and direct chill grain refined (DC-GR) samples. Optical metallography showed extensive peripheral coarse grain (PCG) for the DC, DC-GR and MC-DC planks extruded from the homogenized standard AA6111 billets while planks extruded from modified AA6111 billets (with recrystallization inhibitors) showed thin PCG band. The co-addition of recrystallization inhibitors Mn, Zr, and Cr with elimination of the billet homogenization step had a favorable impact on the microstructure of the AA6111 alloy following the extrusion process where a fibrous grain structure was retained across the whole section of the planks. The mechanical properties of as-cast planks extruded from non-homogenized billets were similar to those extruded from homogenized billets. Eliminating the homogenization heat treatment step prior to extrusion has important ramifications in terms of processing cost reduction.

Sustainable Manufacturing and Optimization of Squeeze Stir Cast Rods Using Recycled Aluminum and Alumina Reinforcements

This work focusses on the production of sustainable metal metrics composites MMCs. The scrap aluminum alloy wheel (SAAW) was used as a metrics and alumina is used as a reinforcement. The process parameters (namely squeeze pressure and time, die preheating temperature and stirrer speed) were optimized using Taguchi method to produce the alumina reinforced-aluminum matrix composites (AMCs). These stir-casted composites were characterized based on their hardness, tensile and compression strengths and wear/tribological properties. The results showed that addition of alumina to aluminum matrix has improved the mechanical and tribological performance. From, Taguchi analysis the optimized 9 approaches (L1 to L9) were obtained and, L5 and L6 methods showed optimum mechanical properties with 100 MPa squeeze pressure, 30 to 40 sec squeeze time, 250 to 350°C die preheating temperature and 450 to 525 rpm stirrer speed process parameters. It was found that properties are process parameters dependent. The produced AMCs have many potential industrial applications including applications in piping industry.

Methodological Study of Evaluating Future Lightweight Vehicle Scenarios and CO2 Reduction Based on Life Cycle Assessment

Changing the material composition of vehicles from steel to alternative materials, such as aluminum and magnesium, is being explored to reduce the weight of vehicles. Further, this change could lead to a significant reduction in vehicular CO2 emissions. To analyze this relationship and estimate the CO2 reduction effect over the life cycle, it is important to create potential scenarios by considering the logistics balance from material production to recycling. Therefore, this study aims to quantitatively predict the amount of renewable energy employed in vehicles, along with the various alternative materials used; further, the demand for aluminum and magnesium is predicted. These predictions are made via several multivariate analyses and a dynamic substance flow analysis (SFA) to explore future scenarios. It is estimated that 65% of rolled aluminum can be obtained from a secondary alloy via closed-loop recycling of rolled products in a sustainable development scenario. However, 510 kt/year of end of life scrap aluminum must be imported from overseas to provide 90% of the secondary alloy required in cast and die cast parts. The overall CO2 reduction amount is predicted to be 3920 kt/year in the 2040 sustainable development scenario. This study successfully demonstrated that combining SFA and life cycle assessment is efficient for quantitatively estimating the synergies of renewable energy implementation, vehicular weight reduction, and recycling.

Melt Conditioned Direct Chill (MC-DC) Casting and Extrusion of AA5754 Aluminium Alloy Formulated from Recycled Taint Tabor Scrap

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.

Kilowatt-Scale Fuel Cell Systems Powered by Recycled Aluminum

Presented here is a novel system that uses an aluminum-based fuel to continuously produce electrical power at the kilowatt scale via a hydrogen fuel cell. This fuel has an energy density of 23.3 kW h/L and can be produced from abundant scrap aluminum via a minimal surface treatment of gallium and indium. These additional metals, which in total comprise 2.5% of the fuel’s mass, permeate the grain boundary network of the aluminum to disrupt its oxide layer, thereby enabling the fuel to react exothermically with water to produce hydrogen gas and aluminum oxyhydroxide (AlOOH), an inert and valuable byproduct. To generate electrical power using this fuel, the aluminum–water reaction is controlled via water input to a reaction vessel in order to produce a constant flow of hydrogen, which is then consumed in a fuel cell to produce electricity. As validation of this power system architecture, we present the design and implementation of two proton-exchange membrane (PEM) fuel cell systems that successfully demonstrate this approach. The first is a 3 kW emergency power supply, and the second is a 10 kW power system integrated into a BMW i3 electric vehicle.

High-Power Fuel Cell Systems Fueled by Recycled Aluminum

Presented here is a novel system that uses an aluminum-based fuel to continuously produce electrical power at the kW scale via a hydrogen fuel cell. This fuel has an energy density of 23.3 kWh/L and can be produced from abundant scrap aluminum via a minimal surface treatment of gallium and indium. These additional metals, which in total comprise 2.5% of the fuel’s mass, permeate the grain boundary network of the aluminum and disrupt its oxide layer, thereby enabling the fuel to react exothermically with water to produce hydrogen gas and aluminum oxyhydroxide, an inert and valuable byproduct. To generate electrical power using this fuel, the aluminum-water reaction is controlled via water input to a reaction vessel in order to produce a constant flow of hydrogen, which is then consumed in a fuel cell to produce electricity. As validation of this power system architecture, we present the design and implementation of two example systems that successfully demonstrate this approach. The first is a 3 kW emergency power supply and the second is a 10 kW power system integrated into a BWM i3 electric vehicle.

Utilización de material de espuma flex (poliestireno) para la construcción de modelos en los procesos de fundición

This research aimed to lower the cost of smelting using flex foam material (poliestireno) for the production of models in foundry processes aluminum and brass. The importance of using this type of material is emphasized, as it reduces the time of process models design and implementation of this method which makes a contribution to the environment by reducing deforestation and pollution. The conclusions of this article point to the vital importance of implementing this new method because it reduces the great mountains of scrap aluminum, bronze and flex foam waste, helping to develop new methods of casting and caring for the environment and the community to do use of it.. Index Terms— Metallurgy, scabs, manufacture, scrap, wash