Finite Element Analysis Of Stress Field Of Carbon Nanotubes Reinforced Magnesium Matrix Composite

In recent years, magnesium matrix composite of new high-strength lightweight composite materials developed rapidly. It has a high electrical and thermal conductivity, high specific strength and specific modulus, excellent damping properties, mechanical properties, high hardness and good wear resistance. Not only is the aerospace and other structural materials widely used, that can be used as aircraft components, hull, load-bearing structure and the support base material of the buffer, which is a new material with broad development prospect. Traditional materials reinforced metal matrix composites include: fibers, whiskers, particles. And carbon nanotubes have attracted much research attention with a high strength, low density and good stability as an ideal reinforcement material. The size of carbon nanotubes as a reinforcing phase is very small, so experimental operations become more difficult. Therefore, finite element analysis software can be used for mechanical properties of composite materials to expand the application of the carbon nanotubes reinforced composite material.In this paper, the density functional theory, continuous medium mechanics and the corresponding software MS and ANSYS were used to solve the mechanical properties of carbon nanotubes reinforced magnesium matrix composite calculations. The main content of the research include the following:(1) In this paper, the first part of the research simulation is based on density functional theory of quantum mechanics program CASTEP module of MS. And when the model contains hetero atoms, the default defects and different aspect ratios and the same degree of tension, binding energy is calculated to analyze the effect of the stability of the mechanical properties of carbon nanotubes. It was found that in the same tension degree, the intrinsic stability of carbon nanotubes are weakest.(2) The second part, the theory of continuous medium mechanics and finite element software ANSYS were used to build different aspect ratios and different phase angle of carbon nanotubes for the effect on the carbon nanotubes reinforced magnesium matrix composite stress. It found that stress has a substantially symmetrical distribution of carbon nanotubes axially. An aspect ratio of 5 and axial distribution of two models of carbon nanotubes is 60?, whose the maximumvalue of stress are minimum. It was indicated that at the same tensile degree, mechanical properties of these models are the best.(3) The third part of this paper studied the effect on stress of the composite material under tensile deformation with defect defect.Simplified models include composite materials with no defects, vertical defects, transverse defects and toroidal defects. It was found that when the composite materials had the tensile deformation, the model of vertical defect defect is the easiest to break, and the model of toroidal defects is the most difficult to destroy.