The Study Of Dynamic Behavior Of Particle Reinforced Metal Matrix Composites Based On Multi-scale Cohesive Zone Model

Excellent mechanical properties of particle reinforced metal matrix composites(PRMMCs) are the base of applications in the military and civilian areas, understanding the mechanical behavior of PRMMCs is the key to design particle reinforced composite material. In the factors that influence the mechanical behavior of PRMMCs, the interface between the particles and the matrix has an extremely important influence on the mechanical properties of PRMMCs,Predict the influence of interface on PRMMCs mechanical properties is the key to its design and application. Traditional micromechanics can predict the static mechanical properties of PRMMCs well, but this method cannot capture the effect of microscopic damage in the interface on the macro mechanical properties of PRMMCs, the numerical description of microscopic damage of the interface is a difficulty and a keynote of current prediction method.The main work of this paper is as follows:1. We established a cohesive zone model based on Cauchy-Born rule and MEAM potential, this model is a multi-scale interface model based on the atomic configuration of interface. Compared with the traditional cohesive zone model, this model can describe the normal and tangential mechanical behavior of the interface, compensate the defects of traditional CZM. The validity of the multi-scale cohesive zone model through building an ABAQUS VUMAT and using an example was verified;2. We established the representative volume element with multi-scale interface based on Voronoi diagram, with random spatial distributions of SiC particles and uniform particle size distributions, the model can be used to study the effect of SiC volume fraction and particle distributions on the dynamic mechanical behavior of PRMMCs effectively;3. We studied the dynamic behaviors of PRMMCs based on multi-scale cohesive zone models and VRVE, the results show that: 1) The true stress-strain curves of VRVE with different particle distribution are similar, which means VRVE is representative, and different particle distribution will change the damaged area of PRMMCs; 2) By analyzing the damage evolution process of PRMMCs, it can be seen that, the multi-scale cohesive zone model can capture the microscopic damage of interface, and reflect the influence of microscopic damage of interface on the macroscopic mechanical properties of PRMMCs; 3) The particle volume fraction has obvious effect on the true stress-strain curves, while the volume fraction of SiC particles is 20% in PRMMCs, the flow stress is higher, but damage appears earlier.The multiscale cohesive zone model can capture the effects of interfacial micro injury on dynamic mechanical properties of PRMMCs. This paper solved some problem of the interfacial numerical description, laying the foundation for the later research.