Molecular Dynamics Simulation Of The Damage In Single Crystal Copper Component With Crack

The essence of the Molecular Dynamics Simulation is to create a particle system to simulate the research object, on the basis of calculating all of the particle’s motion in the numerical calculation system. According to the statistical average, the macroscopic properties of this system can be obtained. It is a tool that research on the atomic and molecular scale material properties. Furthermore, it is of great significance to reveal the mechanics of materials at the nano-meter level behavior.This paper which uses the two dimension triangle modeling to simulate the three dimensions faced centered cubic lattice structure, selects embedded atom potential function, and Fortran programming language to write molecular dynamics programming. According to the basic principle of molecular dynamics, this paper derives the expressions of interactions between the atoms, and establishes a molecular dynamics model to simulate the process of single crystal copper’s tensile, shear and bending. By the tensile comparation of ideal single crystal copper plate and single crystal copper plate with crack, we can know that the existence of crack has very important influence to the strength and elastic modulus of the single crystal copper plate. This paper also simulates the expansion of the prefabricated crack in the model under different loading ways. Combined with the model’s potential energy and the average stain curve in the process of loading, it analyzes the time of crack’s extension and the failure process of the model. By the single crystal copper with prefabricated crack is simulated in the shear stress, failure mode and crack extension model are obtained.By the bending process simulation of ideal single crystal copper beam and crystal crack, the changes of atomic are analysed. Combined with the potential energy of the system and the lateral displacement curve, the crack influences on the bending properties are obtained. Through the comparison of single crack and multi crack propagation in single crystal in the process of bending and extension of copper beam reason, the general form and essence of the crack propagation of crack propagation are obtained.