3.1.1 Automotive sector

The first automobile in the world (1885–1886) was made up of steel, a dense alloy, in most of its parts. With increasing efforts to improve fuel efficiency and energy efficiency as well as to reduce the cost of the vehicles, there was a shift from usage of steel to aluminum (owing to its lower density) that substantially reduced the weight of the automobiles. However, in recent years, driven by lower density of magnesium (33% lighter than Al), car manufacturers such as Porsche, Suzuki, and General Motors are increasingly using magnesium-based materials primarily due to their excellent specific mechanical and physical properties. Among several magnesium alloys, Mg-Al-based alloy series such as the AZ and AM alloys; Mg-rare earthbased alloys, i.e., WE43 and E21; and ZK alloys demonstrate good strength and ductility combination at room temperature along with good resistance to corrosion (salt spray) and superior castability [6]. Hence, they are predominantly being used in the automobile sector as sheets or even engine blocks and other automobile components such as in steering wheels, boot area, etc. Further, for robust and elevated temperature applications such as engine blocks, newly developed highstrength magnesium alloys and alloy nanocomposites can be used as they demonstrate good thermal and dimensional stabilities [7–11].
