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Lightweight construction has been in the focus of industry and the research community for years. However, although lightweight construction usually results in higher weight reductions than a mere substitution of a material could achieve, in practice, designers try to use different materials in lightweight construction. From a technological point of view, a combination of lightweight construction and materials has the greatest potentials. Therefore, one should also be familiar with the limitations of lightweight material construction. The application of nanotechnology in the construction industry and building structures is one of the most prominent priorities of the research community. The outstanding chemical and physical properties of nanomaterials enable several applications ranging from enhancement in strength to self-cleaning properties. It is known that concrete is the leading material in structural applications, where stiffness, strength and cost play a key role in the high attributes of concrete. Among the most effective nano additives that readily improve concrete properties, are (i) nanosilica and silica fume, (ii) nanotitanium dioxide, (iii) iron oxide, (iv) chromium oxide, (v) nanoclay and cellulose, (vi) CaCO3, (vii) Al2O3, and (viii) carbon nanotubes. Moreover, self-cleaning attributes have already been offered to tiles making them easier to clean, having less use of aggressive detergents, causing a lower environmental impact. In particular, by coating solid surfaces by titanium dioxide particles it confers them self-cleaning features, when exposed to light, as dirt hardly adhere on such hydrophilic surfaces. Additionally, when it comes to insulation materials, the use of aerogels nanoporous materials riddled with air-filled pores – provides them with low density and weight and superb insulating abilities, and therefore aerogels find high-tech applications such as space exploration.

Lightweight bricks and tiles allow for quicker and easier construction times, therefore saving time and labor costs overall, while they must be resistant to structural/load bearing. Even more important is the safety aspect. Because lightweight bricks and tiles are easier to move around site, work is in turn made safer as risk is minimised. Regarding transportation, lightweight bricks and tiles are also better for the wider environment as less carbon emissions are given off while in transit. Transportation will also be cheaper as a result of travelling with a lighter load. While the weight of materials is known to reduce installation time, the fact that several lightweight tiles can be installed at once rather than one at a time will also ensure that he installation will be completed faster, while sacrificing nothing on durability, aesthetics or performance. Two approaches to lightweighting have been taken by tile makers: the use of foaming agents and design changes. Foaming agents create air-filled voids that reduce the weight of the finished product and enhance thermal insulation properties. Agents such as silicon carbide can help produce tiles that are up to 26 % lighter while maintaining appropriate mechanical strength and water absorption. In addition, the use of foaming agents allows firing temperatures to be lowered and the expansion process to increase. This enables lower firing temperatures, which reduces energy consumption and costs. On the other hand, regarding lightweight bricks different nano-porosifying agents have attracted the interest of industry, including carbon black, diatomaceous earth, and kaolin. In many cases, already tested, lightweight bricks performed better than the dense bricks installed in kilns, without maintenance, which usually required extensive rebuilding of the structure every two years.

Reducing structural weight is one of the major ways to improve aircraft performance. Lighter and/or stronger materials allow greater range and speed and may also contribute to reducing operational costs. The most effective way to reduce aircraft structural weight is to reduce the density of structural materials. Ceramics are increasingly being used in commercial and military aircrafts and have been used in space shuttles for many years. Ceramic materials are generally lighter than metals, and this low mass makes them highly appealing to the aerospace industry. However, the cost of working with an advanced ceramic material is such that a clear advantage must be established by using it. Once a benefit has been identified for a product or system (e.g., being able to run at a higher temperature or increased electrical activity), a range of ceramics is available. Advanced ceramics underpin the electronics industry, and therefore such electrical components, including sensors, antennas, capacitors and resistors, are getting increasingly smaller and more capable. Therefore, this is a major area of development for advanced ceramics. Moreover, structural ceramics (crystalline inorganic non-metals) are used in aerospace as thermal barrier coatings (TBCs) in the hot part of the engine. In addition, these materials are being used in composites either as reinforcement and/or as a matrix such as in ceramic matrix composites (CMCs). Being lightweight and tough tends to be a main driver for using a ceramic composite. Ceramics are lighter than most metals and stable at temperatures substantially above high-grade technical plastics. As a result of these and other properties, structural ceramic applications include thermal protection systems in rocket exhaust cones, insulating tiles for the space shuttle, missile nose cones, and engine components. Finally, technical ceramics have been used for various parts of the engine for the past 30-40 years, but a lot of activity currently surrounds the development of silicon carbide (SiC/SiC composites) for use in jet engine turbines, mainly concentrated on the turbine blades. The main driver is fuel efficiency, as engineers seek to run the jet engine without the need for cooling channels that currently stop the metal alloy blades from melting. If the blades were made of ceramic composites, which could deal with temperatures of 1,500-1,600°C, the engine could run at higher temperatures. Energy efficiency would therefore increase, which leads to less fuel and the airplane’s ability to fly further or more efficiently.

Automotive ceramics, are advanced ceramic materials that are made into components for automobiles. Examples include spark plug insulators, catalysts and catalyst supports for emission control devices, and sensors of various kinds. Ceramic parts and coatings offer the distinct advantages of lower fuel consumption (due to their higher operating temperatures, higher thermal efficiency, and lighter weight) and reduced exhaust emissions (because of the more complete combustion of fuel at higher operating temperatures). The outstanding wear resistance of ceramics is also advantageous. So-called thermal barrier coatings of ceramics on metal cylinder heads, piston crowns, and intake and exhaust ports are one example of how the thermal and mechanical properties of ceramics can be combined with the ruggedness of the metal parts that they. Moreover, gas turbines have rotating rather than reciprocating parts, and here the refractoriness of ceramics, their resistance to corrosion and wear, and their light weight make for highly efficient high-temperature operation.

Within the defence industry, advanced ceramics are at the heart of modern armor systems due to their comparatively low weight and high performance during ballistic-scale impacts. Ceramic materials have been developed as an armor material since World War I, while ceramic armor became more widespread during the Vietnam conflict, where boron carbide (B4C) was used in helicopter seats as protection against small-arms fire from the ground. Over time, ceramic armor systems were found to be capable of stopping bullets and other projectiles while being more lightweight than other materials, such as metals. As we move into the 21st century, ceramic materials such as aluminum oxide (Al2O3), silicon carbide (SiC) and titanium diboride (TiB2) are used in aerospace, armored vehicles, and personal armor. The defence industry has been actively seeking novel armor materials that provide superior ballistic performance to existing materials while maintaining or improving the weight advantage. The principal requirement of any armor material is its ability to resist high-energy ballistic impacts. In addition, a reduction in the weight of personal armor is essential to increase a soldier’s maneuverability in the field and alleviate long-term health problems associated with carrying heavy equipment. Furthermore, reducing the weight of armor also benefits vehicles by reducing their fuel consumption and structural strain, as well as helping with long-distance transport and other logistical issues. In addition to ballistic performance and low weight, these capabilities will ideally be features of a material that can be manufactured at low cost.