Molecular dynamics simulation for mechanical properties of magnesium matrix composites reinforced with nickel-coated single-walled carbon nanotubes

Abstract

As the interfacial structure and bonding strength play an important role in determining the mechanical performance of carbon nanotube reinforced metal matrix composite, investigating the interfacial mechanical properties of surface modified carbon nanotube reinforced metal matrix composite becomes one of the key factors for the improvement. The mechanical behaviors of nickel-coated single-walled carbon nanotube reinforced magnesium matrix composites were investigated using molecular dynamics simulation method. The results show that the Young's modulus of the nickel-coated single-walled carbon nanotube/Mg composite is obviously larger than that of the uncoated single-walled carbon nanotube/Mg composite. The results also show that the interfacial bonding of single-walled carbon nanotube/Mg composite can be drastically increased by addition of nickel coating to improve the wettability of the nanotube surface and Mg matrix. Furthermore, the influences of nickel coating number on the interfacial bonding characteristics of single-walled carbon nanotube/Mg composites also were studied. For three types of nickel coating number, i.e. without nickel coating, with one layer of nickel and two layers of nickel, the final pullout interfacial bonding strength of the nickel-coated single-walled carbon nanotube from Mg matrix about are 3.9 and 11.9 times larger, respectively, than that of the uncoated single-walled carbon nanotube. The simulation results have proved that such interfaces can effectively transfer load between the nanotube and magnesium matrix in the carbon nanotube/Mg composite, and this will provide the theoretical and experimental basis for the interface mechanics design of the carbon nanotube reinforced composites.