Colloquium: Dr. Meysam HaghshenasDr. Meysam Haghshenas Department of Mechanical Engineering University of North Dakota Grand Forks, ND
Magnesium Nanocomposites: Lightweight, but Strong, Materials of Future
Ambient and elevated temperature mechanical and physical properties of traditional materials like metals, polymers and ceramics are not able to match expected properties in modern engineering applications. Among metallic materials, magnesium (Mg) possesses the least density and seems an excellent candidate for aerospace and automotive industries; however, However, the ductility of Mg alloys is relatively poor because of the low symmetry hexagonal close-packed (HCP) internal lattice structure, which significantly hinders their usage. The precipitation hardening of Mg improves the mechanical properties but there are only a few elements which form extended regions of solid solutions with Mg. Therefore, efforts are spent to develop lightweight Mg matrix composites. With the growing availability of ceramic and metallic nanoparticles, the development of new magnesium nanocomposites provides improved mechanical properties, as well as high temperature, corrosion, fatigue and wear properties over magnesium alloys and conventional magnesium composites reinforced with micron-size particles. The use of a small volume fraction of nano-size reinforcements (i.e. ceramic nanoparticles and carbon nano-tubes) has been shown to produce results comparable or even superior to that of metal matrix composites reinforced with similar or higher volume fraction of micron size reinforcement.