Simulation Study On Stress And Strain Field Distribution Of TiC/SiC Particle Reinforced Aluminum Matrix Composites

Unit-cell models,two particles models and multi-diameter particles models are employed in this paper to simulate the stress and strain distribution of Particle Reinforced Metal Matrix Composites under tensile load by using finite element method.The purpose of this paper is to study the influence of particle size,relative location,volume fraction,interfacial strength on the distribution of stress and strain,in order to analyze the deformation mechanism of composite materials.The main research content is divided into three parts,firstly studying the stress and strain distribution near reinforced paritcles with unit-cell models,and then studying the interaction between adjacent particles with two particle model,finally analyzing the enhancement effect of multi-diameter particles.After a large number of simulation calculations and compared with the experimental results,we found that the deformation of the composite is concentrated in the matrix under the tensile load,and there is a region with higher strain in the matrix along the loading path,which can promote the formation of voids near the particles.And the location of the highest strain is not in but away from the interface in the models with the perfect interface.The distance of the location of the strain peak from the interface is relevant to the size of the particles and it is calculated that the ratio between the distance of the location of the strain peak from the interface and the radius of the particle is close to 0.3.The stress and strain in matrix near the particle is gradually decreasing from near to far.It is calculated that there is a critical distance for the stress and strain of the particles influence with each other,and the critical distance is increasing with the increase of particle size.When the volume fraction are same,the degree of uniformity of the stress distribution will increase with the decrease of particle size,and that result in the fracture toughness of the composite will increase with the refinement of the particles.Multi-diameter particles enhancement will make the stress distribution in the matrix more uniformly,the probability of microcrack initiation in the composites is greatly reduced when the defomation is small,and the overall plasticity and toughness will be improved.