Effect of magnesium on some mechanical properties of 1200 Aluminium alloy

This paper investigated the effect of magnesium as a dispersion strengthening material on some mechanical properties of 1200-Aluminium (Al-Fe-Si) alloy, a typical commercial aluminium alloy used in the production of household utensils. 1200-Aluminium (Al-Fe-Si) alloy containing varying percentages of the dispersion hardening material (i.e. Magnesium) were produced and mechanical tests namely; hardness, tensile strength and impact strength were carried out. Also, the microstructures of the cast materials were studied. The results showed that increase in magnesium content, as dispersion hardening material improved the hardness, tensile strength and caused a slight decrease in impact strength of the 1200-Aluminium alloy. It is inferred from this work that using magnesium as a dispersion hardening material brings about corresponding improvement in some mechanical properties of 1200-Aluminium (Al-Fe-Si) alloy. Keywords: Magnesium, Aluminium alloy, dispersion strengthened, reinforced alloy, crystallographic formation Depth, Geothermal Energy

Powder Injection Moulding and Liquid Phase Sintering of Aluminium - SiC Particulate Composite

Metal matrix composite has been increasingly appreciated by many engineering applications due it its tailored properties for specific uses. Powder injection moulding is one of the most effective composite processing essentially for small and complex parts. Moulding of feedstock is the key step determining green and sintered properties. This research investigated effects of moulding parameters which are % solid loading and moulding speed on microstructure and properties of aluminium composite. Commercial aluminium alloy powder and SiC particulate at 15 vol.% addition were formulated at 55 % and 60 % solid loading. Injection moulding were operated using a horizontal screw driven typed machine at 1600-1800 rpm speed and 280 - 300 °C moulding temperature. After sintering at 655 °C, property assessment via microstructure, density, % shrinkage, distortion and hardness were carried out. It was found that feedstock of 55 % solid loading occasionally led to flash problem while that of higher solid loading experienced higher viscosity to fulfill four-cavity mould. Moulding speed investigated did not significantly affect mould filling and overall properties. Sintered microstructures generally showed well-distributed SiC particulate in the aluminium matrix. The optimum injection moulding condition was the feedstock prepared at 60% solid loading, moulding at 1800 rpm speed, which offered theoretical density of greater than 98.5 % and micro Vickers hardness of 125.2 Hv.

THE INFLUENCE OF CHEMICAL COMPOSITION AND HEAT TREATMENT ON THE MECHANICAL PROPERTIES AND WORKABILITY OF THE ALUMINIUM ALLOY EN AW 5454

The influence of chemical composition and heat treatment on the mechanical properties and formability of the selected commercial aluminium alloy EN AW 5454 was investigated. The main properties of alloy 5454 from the AA 5xxx series are very good corrosion resistant and has good formability. From the cast slab a 50 mm thick slice was taken in the width cross section in the slab centre. One half of the slice was homogenised for 10 hours at a temperature of 530 °C. The cast and homogenised samples were investigated using light and scanning electron microscopy. For the study of the influence of the heat treatment, samples in the as-cast state were annealed in the laboratory furnace at a temperature of 530 °C for 4, 6, 8, 10 and 12 hours. To study the influence of chemical composition, four different samples were prepared: the first without additions, the second with an addition of 1 wt% Mn, the third with 3 wt% Mg and the fourth with an addition of both elements, Mn and Mg. The XRF analyses confirmed the desired chemical composition of all four produced alloys. Half of each alloy’s sample was homogenised at the same temperature and time as the base alloy in the as-cast state. The hot deformation behaviour of the different alloys was investigated using cylindrical hot compression tests performed on a Gleeble 1500D thermo-mechanical simulator. By comparing flow curves a high influence of the thermo-mechanical parameters on the alloy formability can be seen. The alloy has good workability and with the addition of Mn and Mg, the stress values are higher than those of the base alloy.

Removal Efficiency of Acid Red 18 Dye from Aqueous Solution Using Different Aluminium-Based Electrode Materials by Electrocoagulation Process

This work compares commercial aluminium electrode for use in the treatment of wastewater by electrocoagulation process against waste aluminium cans electrode. The applicability of the waste aluminium cans electrode was tested for decolorization of Acid Red 18 dye as a model pollutant. The batch electrocoagulation process using both types of electrode was conducted at a current density of 25 mA/cm2, a pH of 3, an initial concentration of 100 mg/L and 25 min of reaction time. The elemental composition and surface morphology of both electrode materials and the sludge produced were analyzed using SEM-EDX to establish the correlation between the properties and characteristics of both electrode materials with their dye removal performance. The results demonstrated that waste aluminium cans performed better than commercial aluminium electrode with a removal efficiency of 100% in 25 min of reaction time. This was due to the higher Al dissolution of waste aluminium cans electrode that contributed to the larger amount of Al3+ released into the solution to consequently form more flocs to remove the dye molecules. In conclusion, the proposed waste aluminium electrode was considered as efficient and cost-effective and had the potential to replace the conventional ones in treating colored industrial wastewater using electrocoagulation process.