The growing demand for more fuel-efficient vehicles to reduce energy consumption and air pollution poses a challenge for the automotive industry. Aluminum has seen increasing interest in automotive applications due to the general need for weight savings to further reduce fuel consumption in recent years. In particular, there is growing interest in sheet metal applications for light structural arts and body-in-white construction and major efforts have been made by all major manufacturers of semi-finished aluminum alloy products to meet the key requirements which are: Say no to plagiarism. Get a tailor-made essay on “Why violent video games should not be banned”? Get the original essay • Enough strength for structural stability and durability, dent resistance and impact resistance. • Good formability for stretching, bending and deep drawing operations (including anisotropy and springback control). • Metal joining techniques, such as welding, clinching, glowing, brazing, etc. .• Recyclability and low material and manufacturing costsIn order to meet the various requirements for mechanical properties, a good knowledge of the specific behavior of the materials and an understanding of the underlying metallurgical effects involved is important. The main requirement for many sheet metal applications is to find the most suitable combination of sufficient strength and good formability. For structural parts and for body-in-white (BIW) applications, the two main alloy systems used are Al-Mg and Al-Mg-Si which are well accepted due to their good combination of properties. required. Aluminum alloy: We are in a multi-material world where no single material has power and influence on the automobile. Aluminum is the increasingly popular material, offering the quickest, safest, greenest and most cost-effective way to increase fuel economy and reduce total carbon emissions. Reducing vehicle weight – without reducing vehicle size – will be essential as automakers develop the next generation vehicle. Some of the main properties of this metal are: • Weight: Aluminum is light. The density of aluminum is? = 2.7 g/cm3, or a third of that of steel. • Resistance: Aluminum is resistant. Aluminum alloys have tensile strengths that vary from 70 to 700 MPa. Unlike steel, aluminum does not become brittle at low temperatures. Indeed, when cold, the strength of aluminum increases. • Flexibility: its strength is combined with its flexibility, which means that it can bend under load and rebound under the force of impacts. • Malleability: it is extremely malleable and can be extruded into any required shape by passing it through a die. It can be hot or cold extruded and can be further manipulated by operations such as bending and forming. • Conductivity: It has excellent thermal and electrical conductivity. An aluminum conductor weighs about half the weight of a copper conductor with the same conductivity.• Reflectivity: it is a good reflector of light and heat.• Corrosion resistance: aluminum reacts with oxygen air to form a thin microscopic layer of oxide. The layer is only 4 nanometers thick but provides excellent corrosion protection. [7] Aluminum alloys are classified into two types: cast aluminum alloys and wrought aluminum alloys. Table 1 shows the designation system foraluminum alloys, which are used by the Aluminum Association of the United States, for both cast and wrought aluminum alloys. This designation system uses a four-digit numerical system to distinguish different aluminum alloys. The nomenclature of wrought alloys has been agreed and accepted by most countries and is also called the International Alloy Designation System (IADS). The alloy group is indicated by the first digits and the last two digits identify the aluminum alloy or specify the purity of the aluminum. The second number indicates changes to the impurity limits of the original alloy. In the cast alloy designation system, the first digit is essentially the same as for wrought alloys, while the second two digits serve to identify a particular composition. Cast Aluminum Alloys As cast aluminum alloys are economical and environmentally friendly lightweight materials, they are attracting increasing interest in the automotive industry. The properties such as better castability, high mechanical properties, ductility and good corrosion resistance have enabled them to replace steel and cast iron for the manufacture of critical components[11]. Cast aluminum alloys contain a high percentage of alloying elements; the most important alloying elements are: Silicon: Silicon is one of the main alloying elements used for cast aluminum alloys. Generally presents a content between 5 and 12% by weight. Firstly, these alloying elements make it possible to increase the fluidity of the alloys and, therefore, to improve their castability and reduce the coefficient of thermal expansion of the alloys. Presents a low density (2.34 g/cm3) determining a reduction in the weight of the cast components and finally, its low solubility in aluminum allows the precipitation of pure and hard Si particles which improve the abrasion resistance of the 'alloy. Copper: Copper increases both the mechanical strength and machinability of alloys; reduces the coefficient of thermal expansion and, as the most important characteristic, has a negative effect on the corrosion resistance of alloys. Magnesium: Magnesium provides an increase in mechanical properties through the precipitation of hardening precipitates of Mg2Si, thereby improving the corrosion resistance and weldability of alloys. Manganese: It improves tensile properties and significantly increases resistance to low cycle fatigue. Adding manganese also improves the corrosion resistance of the alloy. Iron: Iron is the most common and inevitable impurity in Al-Si foundry alloys because it can form different types of intermetallic compounds; such compounds are fragile and have a detrimental effect on the mechanical strength of the components. There are several types of Fe-rich phases, such as ?-Al5FeSi, a-Al15Fe3Si2 and a'-Al8Fe2Si. Wrought Aluminum Alloys Wrought aluminum alloys are widely used in the automobile industry to produce different components , due to their mechanical properties, which are higher than those obtained from cast aluminum alloys. Approximately 85% of aluminum applications come from wrought aluminum alloys. They are first cast in the form of ingots or billets, then worked mechanically hot and/or cold to obtain the required shape. The crystalline structure of Aluminum, the face-centered cubic (fcc) system, offers good cold formability. For wrought applications, the addition of alloying elements improves most mechanical properties; even though they contain comparatively fewer elementsalloy, the structure of wrought alloys offers better mechanical properties than cast alloys. Plastic deformations increased the degree of grain refinement and homogenized the microstructure. There are four important processes applied to obtain different products: 1) The product obtained by rolling: plates, flat sheets, stained sheets and sheets. 2) The product obtained by extrusion: extruded rods, solid and hollow shapes, profiles or tubes. 3) The product obtained by forming: rolled or extruded products are formed to produce complex shapes. 4) Products obtained by forging: they present complex shapes with superior mechanical properties. Due to increasingly strict requirements for vehicle safety and comfort, the size of many vehicle components is increasing, leading to an increase in the total vehicle mass. For vehicles powered by a combustion engine, reducing vehicle mass helps reduce fuel consumption and, therefore, ownership costs and the amount of carbon dioxide emitted into the atmosphere. Aluminum alloys used for the construction of motor vehicles are one of the methods of reducing the mass of the vehicle, as the density of aluminum alloys amounts to 2,700 kg/m3, or one third of that of the steel (7,600 kg/m3). To guarantee mechanical properties comparable to those of steel, it is necessary to use aluminum elements with larger cross sections than steel elements. Therefore, the reduction in average mass is slightly less than the reduction resulting from simply comparing the density values ​​of the two materials. The reduction in efficiency of the aluminum alloy element compared to the steel one amounts to approximately 50%. The direct reduction in vehicle mass causes the so-called “secondary” mass reduction, which is the effect of smaller dimensions and dimensions necessary for other structural elements of the vehicle. The 5000 and 6000 series alloys, which make it possible to construct almost the entire body structure of a motor vehicle, are of particular interest in the automotive industry. Using the 6060-T6 alloy, a space frame-based design of the vehicle was developed that meets the requirements of the Federal Motor Vehicle Safety Standards for frontal impact testing. [5]History of aluminum in automobiles: Today, aluminum is a key material for automobile manufacturers. The first sports car with an aluminum body was unveiled at the Berlin International Motor Show in 1899. Two years later, the first engine with aluminum components was developed by Karl Benz. After World War II, aluminum had become economical enough to be used in mass-produced vehicles. An innovation occurred in 1961 when the British company Land Rover produced V-8 engine blocks made with aluminum cylinders. From there, aluminum automotive components gained a foothold in wheels and transmission cases, then moved to cylinder heads and suspension joints. This infinitely reusable metal is now the leading material used in drivetrain and wheel applications and continues to gain market share in hoods, trunks, doors and bumpers - as well as complete structures vehicles. [6] Applications of Aluminum Alloys in the Automotive Industry: Optimized aluminum-oriented car design has been established in various parts and applications in the automotive industry (see Figure 3): • Powertrain – Engine Block and cylinder head, crankcasestransmission, fuel system and radiators. : 69 kg• Chassis and suspension - Subframe, axle, wheels, suspension arms and steering systems: 37 kg• Bodywork - Body in white (BIW), bonnets/bonnets, doors, front structure, fenders, crash elements and fenders -shocks and various interiors: 26 kgIn Figure 5, the relative and absolute mass savings obtained by using aluminum alloys for the manufacture of automobile components have been reported. It also shows the market penetration for each individual component. Over the last forty years, we can observe in Figure 6 that the percentage of aluminum cars has experienced a strong and continuous increase, due to the growing demand from the automotive industry to use lightweight materials. Two types of alloys are used for most aluminum automotive components: I) Non-heat-treatable or work-hardening Al-Mg (Mn) alloys (5000 series alloys) which are a solid-hardened solution, showing a fair combination strength and formability.II) Heat treatable Al Mg Si alloys (6000 series alloys) which achieve the desired strength through heat treatment processes, for example for sheet metal when the car body undergoes the baking process paint. For some components, such as bumpers and crush zone, high strength Al-Zn-Mg-Cu (AA7xxx) is used. These alloys have been developed and are currently widely used in the aerospace industry as well, due to their high mechanical performance. Extrusion: Another important area of ​​aluminum solutions and applications is the well-established technology of aluminum extrusions. Here, very complex profile shapes can be made, enabling a lightweight and innovative design with integrated functions. Typically, medium strength AA6000 and high strength AA7000age hardening alloys are used, as the desired quenching occurs during the extrusion process. Formability and final strength are controlled by hardening the forage by heating. Extrusions are made for the bumper beams and crash elements/boxes. The main driving factors for new developments are extrudability, tolerances and strength, especially for strength applications in automotive vehicles. New alloys are being developed that have higher strength. At the same time, it is easier to extrude and, moreover, complex shapes can be produced, such as drawing thin-walled shapes. Today, extrusions are widely used where tight tolerances can be compensated for manually. [3] Casting: The growing volume of aluminum components in automotive applications are castings, such as engine blocks, cylinder heads, wheels and special chassis components. However, due to the high requirement for strength and durability, cast iron is still often used. Significant advances in the development of aluminum alloys (Al-Si-Cu-Mg-Fe type) and better control of processes and casting methods have improved material properties and functional integration that enable the aluminum to meet high specific requirements. Aluminum castings are also gaining acceptance in the construction of space frames, axle parts and structural components. Complex parts are produced by high-integrity casting methods that ensure optimal mechanical properties and enable improved functional integration. [3]Advanced Multi-Material Design Concepts “MM”Multi-material design is theinnovative concept of motor vehicle, which is currently being developed by the automobile industry. The basic idea of ​​this concept is to use the "best" material for the components of each car, which makes it possible to produce a lightweight car with reduced emissions, without losing performance and above all the safety of the car's passengers. . The materials selected could be aluminum as well as high and ultra high strength steels, magnesium and plastics or composites. This is the primary objective of the “Super Light Car” (SLC) project. [3]Microstructure Evolution (Sheet Production): A flowsheet for the production of aluminum sheet alloys by DC – ingot casting, hot rolling, cold rolling and final annealing treatment is shown in Figure 6. The material is transformed in several steps from the cast structure into a fine-grained recrystallized structure by hot and cold rolling and final solution of soft annealing or heat treatment in a continuous annealing furnace.1) The structure casting with relatively large grains and random texture is usually formed by homogenization annealing. 2) Recrystallized grain structure formed during hot rolling with typical cubic structure and constituent particles stretched in the rolling direction. 3) Grains deformed and fine dispersoids after final cold rolling with typical rolling texture.4) The recrystallized grain structure with a relatively low cube formed after final solution annealing.Mechanical Properties of Aluminum Alloys: Unmixed Aluminum does not have high tensile strength. Due to the addition of alloying elements like manganese, silicon, copper and magnesium, which will improve properties such as strength of aluminum and produce an alloy with properties suitable for particular applications. Aluminum alloys have been widely used and have become a valuable material. in the automotive industry due to its properties such as light weight, strength, recyclability, corrosion resistance, strength, durability, ductility, formability and conductivity. The strength and durability of aluminum alloys vary widely, not only due to the components of the specific alloy, but also due to heat treatments and manufacturing processes. Its resistance can be adapted to the desired application by modifying the composition of its alloys. Mixed with a small amount of other metals, it can provide the strength of steel, with only a third of the weight (The Aluminum Association, 2011). Aluminum alloys increase its strength without loss of ductility. On the other hand, it naturally generates a protective oxide layer and is very resistant to corrosion. Different types of surface treatment processes such as anodizing, painting or lacquering can further improve this property. It is particularly useful for applications where protection and preservation are desired. Due to this distinctive combination of properties, the variety of applications for aluminum continues to grow. Table 3 below shows typical properties of normally used aluminum. Aluminum can be processed in several ways when in a molten state because it is ductile and has a low melting point and density. Its ductility allows aluminum products to be primarily formed towards the end of product design. Another key property of aluminum alloys is their sensitivity to heat. Workshop procedures involving heating are complicated by the fact that aluminum, unlike steel, melts without first turning red. Torch forming operations therefore require a certain.