The Effect of Iron Content on Microstructure and Porosity of Secondary AlSi7Mg0.3 Cast Alloy

Abstract

In the present study, microstructure and porosity of AlSi7Mg0.3 cast alloy including various amounts (0.123; 0.454 and 0.655 wt. %) of iron were investigated. The alloys were produced as secondary (scrap-based -recycled IntroductionAutomotive -chassis, bodies, engine blocks, radiators, hubcaps, and etc. driven by consumer needs and increasingly tight regulations, the automobile industry has made ample recourse to aluminium. A European car today contains on average 100 kg of aluminium, taking advantage of multiple properties of the materials: lightness (a 100 kg loss of weight reduces fuel consumption by 0.6 litres/100 km and greenhouse gases by 20 %), resistance (improved road-handling, absorption of kinetic energy, shorter braking distance) and recycling (95 % of the aluminium contained in autos is collected and recycled, and represents over 50 % of the vehicle's total end-of-life value). Aluminium coming from recycling can allow 95 % energy savings and 85 % less CO 2 emissions compared to primary aluminium production. Recycling -aluminium can be recycled indefinitely without losing any of its intrinsic qualities. This is a considerable advantage in modern metallurgical industry. For the past 20 years the proportion of metal consumed that is recycled has grown steadily and today stands at something like 30 % of primary metal production (European Aluminium Association; Schlesinger, 2014;Hurtalová et al., 2013).The Fig. 1 shows the fraction of world aluminium production from primary and secondary (recycled) sources. About one-third of the aluminium produced in the world is now obtained from secondary sources and in some countries the percentage is much higher. The process used for recycling aluminium scrap is very much different from those used to produce primary metal but in many ways follow the same general sequence. This sequence begins with mining ore, followed by mineral processing and thermal pre-treatment and then a melting step. The metal is then refined, cast into ingots and sent to customers. Aluminium alloys recyclers also face similar challenges to the producers of primary aluminium; there is need to produce a consistent alloy with the required chemistry, reduce the amount of waste generated, minimize energy usage and manufacture the highest-quality product at the lowest possible cost from raw materials of uncertain chemistry and condition (Mc Millan et al., 2012;Schlesinger, 2014).Commercial Al-alloys always contain Fe, often as undesirable impurity and occasionally as a useful minor alloying

Investigation of the corrosion behavior of aluminum bronze alloy in alkaline environment

“…Under such conditions, water chemistry is constantly changing and structural material of condenser tube experiences such corrosive two‐phase flow with high velocities. [10–12]. The wheel test method was used to create two phase conditions to investigate the corrosion behavior of aluminum bronze coupons in the solution with different pH.…”

“…As a minor alloying element, iron (Fe) has been used sometimes in aluminum bronze alloy to enhance mechanical properties such as hardness. During solidification, iron leads to the formation of complex intermetallic phases, and these phases can affect mechanical properties, especially hardness [12–14].…”

Effect of Heat Treatment Process and Optimization of Its Parameters on Mechanical Properties and Microstructure of the AlSi11(Fe) Alloy

“…The spots marked as EDS Spot 3 and EDS Spot 6 indicate precipitations of the intermetallic β(AlFeSi) phase, which occurs in the form of long platelet-shaped, acicular precipitations visible in the alloy microstructure ( Figure 12 a). β(AlFeSi) phase has an adverse effect on alloy castability [ 72 ], causing a drop in tensile strength, plasticity and impact strength [ 5 , 6 , 73 ], and it conduces to the initiation of cracks [ 10 ] and porosity [ 74 ], as well as worsening machinability [ 75 ]. The EDS Spot 1 is also an Fe-rich intermetallic phase.…”

Processing and characterization of SS316 based metal matrix composite casting through microwave hybrid heating

“…Porosity is one of the major defects in casting. 51 Therefore, less porous castings are preferred. The porosity is measured according to the ASTM B-276 standard by using an inverted microscope (make: Radical scientific instruments) inbuilt with image analyzer software.…”