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Defining construction
Published in Rick Best, Jim Meikle, Describing Construction, 2023
Aluminium is widely used in construction, but it is also used extensively in many other industries including the manufacture of, among other things, truck bodies and cookware. Aluminium extrusions are the basis of window frames and curtain walling used in buildings all over the world. Their production starts with the mining of bauxite and progresses through smelting, powered by large amounts of electricity, to the production of standard extruded sections. A significant proportion of aluminium production also includes recycled material, which adds more complexity to the supply chain question. Some, but far from all, of that production goes to fabricators who manufacture window frames and similar products which are then delivered to, and installed in, buildings of various types. Inputs to the total process include transport (in several stages), energy to drive the mining process as well as the smelting and so on – the question is, how much of the value of all these parts of the process should be considered to be part of the value of construction?
Green manufacturing and environment
Published in S. Thirumalai Kumaran, Tae Jo Ko, S. Suresh Kumar, Temel Varol, Materials for Lightweight Constructions, 2023
Ali Sohani, Jaroslav Vrchota, Burçin Atilgan Türkmen, Mohammad Mehdi Hosseini, Hitesh Panchal
Aluminum could be recycled using the process found in Figure 6.2. Aluminum recycling provides many advantages [13]:Compared to producing aluminum from raw materials, recycling aluminum uses 95% less energy.In addition, 97% of the greenhouse gas emissions produced in primary production are diminished.Approximately nine tons of CO2 emissions are saved for every ton of aluminum recycled. Four tons of bauxite, which is used to produce aluminum, are saved. One thousand kilograms of CO2 are equal to driving over 5600 km.There is a permanent supply of the metal. The material is totally recyclable forever, so every time it enters the recycling loop, carbon emissions diminish.It is 20 times more energy efficient to produce aluminum cans from recycled metal instead of utilizing primitive metal.After recycling empty drink cans, brand-new cans can be sold within 60 days.
Contributing to Sustainable Developments
Published in Yip-Wah Chung, Monica Kapoor, Introduction to Materials Science and Engineering, 2022
Unless we can recycle 100% of these materials, we must still produce raw materials from their ores. For example, aluminum is produced by electrolysis of molten aluminum oxide (bauxite). The carbon footprint of this process comes from two sources. One is from the use of electricity in electrolysis, which depends on how the electricity is produced. The other source is from the use of graphite anodes in the electrolysis cell, which are oxidized to produce carbon dioxide. At the same time, the energy cost of heating and maintaining molten aluminum oxide is high due to its high melting point of over 2000°C. As discussed in the chapter on phase diagrams, it is possible for a two-component system to achieve a lower melting point than the individual components when a eutectic mixture is formed. In this case, it is achieved by adding cryolite (Na3AlF6) to alumina. The eutectic composition of 90% cryolite and 10% alumina gives a melting point of 960°C.
Correlation of microstructure, hardness, and electrical conductivity of hypereutectic Al-Si/B4C composites manufactured by hot pressing technique and subjected to hot extrusion
Published in Canadian Metallurgical Quarterly, 2023
Aluminum (Al) is an important metal due to its attractive properties such as low density, high thermal and electrical conductivity, and good corrosion resistance. These properties enhance the applications of Al and its alloys in diverse industries such as aerospace, automobile, marine, and architecture [1–4]. However, Al is seldom used in its pure form in the industry due to its weak tribological properties, relatively low strength, and low hardness. In choosing the right alloy for a certain application, mechanical, electrical, and thermal properties are considered, along with formability, machinability, weldability, and corrosion resistance. Hence, developing Aluminum materials in alloy or composite forms is necessary to improve the mechanical and physical properties of aluminum metal [5–7].
An overview of blade materials and technologies for hydrokinetic turbine application
Published in International Journal of Green Energy, 2023
Muhamad Hasfanizam Mat Yazik, Chang Wei Shyang, Mohammad Hafifi Hafiz Ishak, Farzad Ismail
Aluminum is a lightweight metal with density a third of steel but has a low tensile strength and less stiffness. It is usually used as testing materials due to its lower fatigue properties compared to steel (Campbell 2008). However, it offers better end-of-use value because it is easier to be recycled compared to other materials. Aluminum can be infinitely recycled without a loss in quality with 95% saving in production energy compared to its primary production (Jupp 2011). This can offset the decommissioning cost, thus aluminum offers a high commercial value along with its prolonged lifetime. Moreover, aluminum is rust free due to its natural oxide layer and can easily be inspected by visual means in addition to any other metal inspection methods. Aluminum can survive harsh marine conditions and can be kept unpainted in normal environmental conditions.
Evaluating the corrosion behaviour of AA6061-T6 alloy and its friction stir welded joints
Published in Canadian Metallurgical Quarterly, 2023
Navdeep Minhas, Lenka Sudheer, Varun Sharma, Shailendra Singh Bhadauria
Aluminium is a light structural metal, which possesses excellent mechanical and corrosion properties when alloyed with other elements such as Si, Mg, etc. Such alloys are extensively being used in diverse business areas, which includes spacecraft components, railways, shipbuilding, aerospace, automobiles, family appliances, electronics, etc., owing to their good structural efficiency, much less weight, low density, high resistance to corrosion, excellent workability and good electrical conductivity. Among the different variants of aluminium alloys, the AA6XXX series alloys show excellent corrosion resistance properties [1]. These alloys own good age hardenability characteristics and are commonly heat-dealt with T4 (natural aging solution therapy) and T6 (aging to the peak) age-hardening conditions [2]. Within the AA6XXX series alloys, the AA6061-T6 grade is the most commonly used age-hardened alloy, which possesses good weldability, top extrudability, and exquisite corrosion resistance. Owing to the good mechanical and corrosion properties, it is used in the fuel plate structure in the research nuclear reactors. Further, the parent AA6061-T6 alloy structure is exposed and the purity of the coolant is not well controlled and subjected to the contamination, which will further allow alloy to corrode [3].